Well, I finally had several good days to begin the construction of my Thien separator. Here is a photo of the nearly finished product. I need to secure the plexiglass and seal some joints, then I will be ready to test the bellmouth outlet. However, before I do another thing, I need to do some serious cleaning of my shop - remind me not to use MDF again! Also, before I can test, I need to do some work on my DC piping.
If you have interest in seeing some of the sequential construction photos, let me know and I will post more. I've included just one so you can see the bellmouth attachment.
(https://www.dropbox.com/s/kespozx8b574ato/Separator-38.jpg?raw=1)
(https://www.dropbox.com/s/mh1313r4jr6g8a4/Separator-24.jpg?raw=1)
Very tidy. I'm looking forward to reading the results.
Dave
I would like to see how you installed your plexiglass. The lexan I used ( 1/8 th inch) had a tendency to snap. I did not place it in a dado, I predrilled and countersunk some holes then tried drilling through that into the wood. It worked well on half the holes, then I hit the edge of a hole in the lexan with the drill bit while holding the lexan in the curve. It snapped as soon as the bit hit the edge.
Looking at the tophat built by galerdude, it looks like that is how he installed his. Not sure.
Thanks, looks very good,
Raymond
Quote from: RCOX on August 26, 2011, 05:11:08 AM
I would like to see how you installed your plexiglass. The lexan I used ( 1/8 th inch) had a tendency to snap. I did not place it in a dado, I predrilled and countersunk some holes then tried drilling through that into the wood. It worked well on half the holes, then I hit the edge of a hole in the lexan with the drill bit while holding the lexan in the curve. It snapped as soon as the bit hit the edge.
Looking at the tophat built by galerdude, it looks like that is how he installed his. Not sure.
Thanks, looks very good,
Raymond
Raymond,
The plexiglass is the primary reason my separator is not 100% complete. I haven't figured out how I'm going to do it. There are two issues, retaining it and sealing it. It is possible that both needs can be met with a single fastening device, but I'm thinking they are going to require separate solutions. If you Google "attaching plexiglass to wood" you will find a lot of information, most of it pretty discouraging. Maybe we should start another thread to solicit ideas and experience on this subject. I know there are several people who have built separators using plexiglass or polycarbonate, but none of them have discussed this constuction problem.
Below is the design sketch I created for my separator. As you can see, the 1/8" plexiglass is held in place by a top and bottom retaining ring. The dado at the top doesn't serve any real purpose other than the plexiglass I had was about an 1/8" too tall and I didn't want to risk trimming that small amount off.
I have not done enough testing yet, but my current plan is to drill oversized holes in the plexiglass and then drive truss head screws radially into the retaining rings. I might put a nylon or rubber washer under the screws, but the whole reason for using truss head screws is to keep the retainer profile very low. I would have countersunk the screws as you did, but several online sources strongly recommended against that because it causes stress points where fractures will occur when flexed.
For sealing I may use silicone caulk, but I would like to avoid that mess. The only other idea I've come up with is to cut a shallow dado all the way around the middle of the retaining rings and then put a piece of rope caulk in the dado.
(https://www.dropbox.com/s/ci2jcm91uzfp83f/Separator.jpg?raw=1)
OUTSTANDING! MORE PICTURES~! :o
Quote from: RCOX on August 26, 2011, 05:11:08 AM
I would like to see how you installed your plexiglass. The lexan I used ( 1/8 th inch) had a tendency to snap. I did not place it in a dado, I predrilled and countersunk some holes then tried drilling through that into the wood. It worked well on half the holes, then I hit the edge of a hole in the lexan with the drill bit while holding the lexan in the curve. It snapped as soon as the bit hit the edge.
Looking at the tophat built by galerdude, it looks like that is how he installed his. Not sure.
Thanks, looks very good,
Raymond
Raymond,
The lexan I used was a little less than 3/16's and I did use screws on the bottom plate of the sandwich to pull it up tight to the edge and to help seal. I pre-drilled and countersunk the holes after pulling it out of the assembly and with it laying flat. On the top, the circular dado is all that holds the lexan in place and the vertical bolts around the perimeter seems sufficiant to seal the top. In my limited experience with using lexan in the sign industry it has been extremely difficult to snap lexan. Many times, 3 to 5" waste strips (3/16") were folded in two to fit in the dumpster, with out breaking. You can try using a heat gun to make it a little more plyable but it does get soft quickly. Acrylic or plexiglass on the other hand is very shatterable, I've seen panels break just from wiping with alcohol (?), don't know why. I do know that plexiglass is fragile and that is why the sign industry uses lexan for large lit panels because it stands up to the abuse. I've shattered lexan in a panel saw and with a skill saw, both with inadequate support. Ideally to saw or drill lexan, it should be supported on both sides and lay flat. That's just my experience and I'm no expert on the subject, just sharing what has worked for me.
Retired2, your new separator really looks good. nice job.
Thanks,
Gale
O.K. Don, you asked for it!!
Here are some cutting and assembly photos of my Thien separator. I have stolen as many ideas and techniques as I could find on this forum. So, if you see something that looks like yours, thank you for your help! I hope I've added a few tricks that might be of use to others.
The following photo shows the baffle sandwiched between the top and bottom plate. The three pieces are pinned together by 1/8" dry dowels. These pins proved very useful several times throughout the cutting and the assembly process. In this photo the sandwich has been bandsawed to reduce the amount of material that had to be routed away. All three pieces were routed at the same time with a 2" long cutter.
(https://www.dropbox.com/s/6hk2bhuyw82bydm/Separator-02.jpg?raw=1)
After the sandwich was edge routed, it was opened up so the drop slot could be routed in the baffle. I didn't worry about cutting into the bottom plate when I routed the slot because in my design the center of the bottom plate is removed.
(https://www.dropbox.com/s/ijpp4n3zmy8t0nj/Separator-04.jpg?raw=1)
Then I removed the baffle, flipped the bottom plate over and routed the trash can groove.
(https://www.dropbox.com/s/3ojwu0uekyiowou/Separator-07.jpg?raw=1)
To finish the bottom plate, I routed out the center, leaving just a ring and a corner to support the inlet pipe.
(https://www.dropbox.com/s/crl97v7nh83lpop/Separator-10.jpg?raw=1)
Next, I created another sandwich for the two plexiglass retaining rings. Again, the dry dowel pins were used which keeps things aligned for several machining operations.
(https://www.dropbox.com/s/qx3nwuk0me1trs2/Separator-08.jpg?raw=1)
These are the completed retaining rings. Dados were cut for the vertical ribs, the center was removed, and the corner was cut out to mate with the inlet port framing.
(https://www.dropbox.com/s/6ph0qf85z7jdt9p/Separator-16.jpg?raw=1)
Next, I completed the top plate. On the bottom side I cut a circular dado to receive the top edge of the plexiglass. Then I cut a hole large enough to insert the bellmouth outlet pipe. For testing purposes I wanted to be able to remove the outlet pipe without having to remove the entire top plate.
(https://www.dropbox.com/s/v4cvencekfaq88v/Separator-21.jpg?raw=1)
This photo shows the outlet pipe in place. It has two collars. One forms the plug for the hole in the top plate, and the second forms the flange for attaching the assembly to the top plate.
(https://www.dropbox.com/s/pjw5opwrrsmfg1h/Separator-25.jpg?raw=1)
Now the assembly begins. I had a circular piece of MDF waste, so I decided to make a stiffener plate for the baffle. It is set well back from the drop slot in order to maintain the 1/4" thick edge. At this point all three pieces are glued together using the dowel pins for alignment.
(https://www.dropbox.com/s/tatkta87ke0nt00/Separator-28.jpg?raw=1)
Next the two plexiglass retaining rings were glued up. You can see screws where the dowel pins once were. That was a blunder and they were removed after this photo was taken. There will be screws inserted in these locations, but they are longer and attach the top plate. Same is true for the bottom plate.
(https://www.dropbox.com/s/76etq21yhqcyfx1/Separator-30.jpg?raw=1)
Next the inlet pipe mount was created by face gluing several pieces of maple. The maple has been machined to provide stops for the plexiglass and to maintain the curvature of the separator's inside diameter.
(https://www.dropbox.com/s/6d02hw7vge6f990/Separator-33.jpg?raw=1)
Next the plexiglass cage is attached to the bottom plate and baffle assembly. Then the plexiglass is cut and checked for fit.
(https://www.dropbox.com/s/gy04t77ry5zol2j/Separator-35.jpg?raw=1)
The inlet port is attached with hex head screws.
(https://www.dropbox.com/s/hmppdlcppryxmeb/Separator-36.jpg?raw=1)
And finally, the top plate is attached.
(https://www.dropbox.com/s/4odq0b45b1cboam/Separator-37.jpg?raw=1)
That is the status of my separator as of today. I'm sure everyone is eager to hear how this bellmouth idea is going to work out. I am anxious to try it as well, but there is still work to be done, and I am on the east coast so I may be testing it as a water pump!!
I am very impressed with this. I laughed my butt off at the water pump testing, I am in Northern Virginia, so I might be joining in on that test. Anyway, I regretfully have to report that my scroll inlet top hat design did not perform as well as I thought. It works, the problem is that velocity drops dramatically just inside of the inlet opening at the curve before entering the baffle. You learn from your mistakes right? But this little number you came up with, yes, I will be making myself one of these the minute I get up from this chair. I am very anxious to see some video of yours running. Great work!
Quote from: Don_Z on August 26, 2011, 01:41:41 PM
Anyway, I regretfully have to report that my scroll inlet top hat design did not perform as well as I thought. It works, the problem is that velocity drops dramatically just inside of the inlet opening at the curve before entering the baffle. I am very anxious to see some video of yours running. Great work!
Sorry to hear the scroll inlet did not work out. The whole time I was working on my separator, I kept wondering if I should have incorporated a scroll. It seemed like a good idea, but a couple things kept me from trying it. First there is the task of fitting an egg shaped separator onto a circular waste drum. Then I kept thinking that the air that has made a full revolution will hit the entrance wall at a pretty blunt angle. That may be an oversimplification of what truly happens, but it seems the once-circulated air should intersect the new air as tangentially as possible. Not sure if that makes sense or not, but that is part of the reason I felt a rectangular inlet slot would be better. It is narrower than a round slot so the two air streams should join up with less turbulance.
Quote from: galerdude on August 26, 2011, 12:46:13 PM
......Acrylic or plexiglass on the other hand is very shatterable, I've seen panels break just from wiping with alcohol (?), don't know why. I do know that plexiglass is fragile and that is why the sign industry uses lexan for large lit panels because it stands up to the abuse. I've shattered lexan in a panel saw and with a skill saw, both with inadequate support. Ideally to saw or drill lexan, it should be supported on both sides and lay flat. That's just my experience and I'm no expert on the subject, just sharing what has worked for me.
Retired2, your new separator really looks good. nice job.
Thanks,
Gale
I'll be keeping my fingers crossed when I finally attach the plexiglass. It wasn't too difficult to bend to the diameter of my separator, but to seat it perfectly, I warmed it with my wife's hair dryer. That softened it up quickly and it snugged right up to the retaining rings.
I've drilled a few test holes and found that brad point drill bits with the spur or lip work much better than a conventional drill bit.
Galerdude: Thank you for the info. I am not sure the polycarbonate I used was actully Lexan or not. My tophat is working for now so I am going to concentrate on my ductwork. I will look for actual Lexan when I do rebuild. Thanks for the information. Curious as to how a dado in the top and bottom panels would work? Just cut the top and bottom, cut the dado all the way to the edge on the entrance side, assemble that part and then just slide the Lexan into the dado so it is a captured fit. I am thinking that should seal it well enough that I wouldn't need to attach or caulk it. Thoughts?
Retired2: Top shelf work. I, like everyone else, am awaiting the results of the belled outlet. Thanks for the pictures, they are very informational.
Everyone on the east side be careful doing this upcoming storm. Hope everyone gets through with dry wood.
Raymond
My experience with polycarbonate is that it does not snap, but I only have 2mm sheet. I suspect that it was not poly.
Also, poly is very temperamental about what you use to clean it with, paint thinners, acetone etc, will cloud the surface. WD40 is good for removing stains. Keep a few offcuts in a draw for testing cleaning products.
Dave
I used OPTIX by Plaskolite Acrylic Sheet.. 0.080" thick.. which is sold at Home Depot in 30x60" clear sheets. Only downside is I only needed @7" width but al most the full 60" length for my top hat and it cost @ $55 for the sheet. There will be other projects.. in fact a few friends will likely do a group build of these soon. Ripped the strip off on a table saw with no problems, wrapped into a 20" dia circle no problem and easily would go much tighter than that with no signs of stress on the material at all. It could be drilled and countersunk lightly, but I didn't need to do that.... just cut the acrylic to length, laid a bead of chalking in the dados, inserted the acrylic and clamped it in place and waited for it to dry. I wasn't satisfied with the adhesion of the chalking, or even PL construction adhesive to the acrylic so I sealed it with "Goop Automotive Adhesive and Sealant". This stuff was developed to attach auto weather striping but I am convinced it will stick anything to anything else. It is about the consistency of silicon sealant, comes in clear form in a tube and forms a flexible air-tight, water-tight bond and can be spread.. costs maybe $8 and can be bought at any auto supply and many other places too. That will seal it for sure. Rather than scratch out my botched bed of chalking, I just ran a bead of Goop around the perimeter of the acrylic window.. top and bottom, and that formed an air tight bond that isn't coming apart in this lifetime. It may not be pretty but it works great.
The 0.080 thickness of the acrylic is plenty strong and robust for this application.
wrt selecting material, I too considered MDF and chose 1/2" construction grade plywood and put the premium side to the center because it's smoother and a few minutes with a ROS finishes it well. Lighter, stronger, easier to work and little dust.. 4' x 4' should do the job in most cases.
I am curious if by adding the stiffener like you did wouldn't that cause added stress or flex on the 1/4 Hardboard? ???
Quote from: Don_Z on August 29, 2011, 09:21:37 AM
I am curious if by adding the stiffener like you did wouldn't that cause added stress or flex on the 1/4 Hardboard? ???
You're pretty sharp Don! Without the stiffener, the baffle was a little springy and I'm sure it would have vibrated. With the stiffener and the added weight, it sags just a tiny bit, but I suspect over time it will droop more. So, I've purchased a 3/16" threaded rod that will be added to support the loose end.
Regards
Well, as since I am building yours verbatim except I am using 1/2" MDF (love the design), I got to thinking when I routed out the hardboard and saw how flimsy it was with the material that was left to support it. So the thought of adding more material to it wasn't clicking right in my head. So I was thinking that rather than cut out the hole completely on the bottom hole of the sandwich completely, what if you just routed out the 1 1/8" cutout and beveled that edge from underneath? Just thinking out loud about this and working on it between stages of my kitchen project.
Don Z.
Quote from: Don_Z on August 29, 2011, 12:50:18 PM
So I was thinking that rather than cut out the hole completely on the bottom hole of the sandwich completely, what if you just routed out the 1 1/8" cutout and beveled that edge from underneath? Just thinking out loud about this and working on it between stages of my kitchen project.
Don Z.
I think that would work fine. There were two things I was trying to accomplish with my baffle design and both created construction problems. The first was to avoid having a ledge along the outside wall of the drop slot. Of course, that meant there couldn't be any dado to hold the bottom edge of the plexiglass. The second thing I wanted was a thin baffle because I seem to recall Phil saying thin baffles worked better that thick ones. Of course a thin baffle needs to have some additional support, so I am stuck with an internal post that I would have preferred not to have.
I am hoping to achieve a compromise of that with the use of a thicker bottom and some creative routing. So, have you tested it yet?
Quote from: Don_Z on August 29, 2011, 02:46:58 PM
I am hoping to achieve a compromise of that with the use of a thicker bottom and some creative routing. So, have you tested it yet?
Sorry to say Don, I'm not even close. My garbage can and top hat design, allowing for raising and lowering the outlet pipe for different test conditions, won't fit under my 50-760 dust collector. So, today I was out buying material to remove the dust collector from the wheeled stand and raise it up on fixed supports. Tomorrow the collector goes into the paint shop for priming, a day later a coat of paint, and then the plexiglass gets attached. I suspect I'm a week away from testing. I'm as slow as a snail, but I prefer to think of it as methodical!!
If being slow isn't bad enough, today my wife found some curtains that she likes better than the ones I just hung for her yesterday. And as you might expect, the rod has to be moved. I don't dare complain or she will shut off all shop purchases.
Do I know how that goes. >:( I have been remodeling our house now and to take time away from that to work on this separator is like stealing from Fort Knox! It has made me rather proficient at multitasking I must say. So what color are you going to paint your DC and are you going to paint the Separator as well? I was thinking of painting mine in a faux metallic finish and giving it a retro 50's post modern machinery look to it. I might even throw in some useless dials and gauges on it as well to have fun with it.
Quote from: Don_Z on August 29, 2011, 03:20:06 PM
Do I know how that goes. >:( I have been remodeling our house now and to take time away from that to work on this separator is like stealing from Fort Knox! It has made me rather proficient at multitasking I must say. So what color are you going to paint your DC and are you going to paint the Separator as well? I was thinking of painting mine in a faux metallic finish and giving it a retro 50's post modern machinery look to it. I might even throw in some useless dials and gauges on it as well to have fun with it.
Sorry Don, I said my collector is going into the paint shop, but what I meant to say was my separator. And the "paint shop" is a pair of saw horses where the separator will sit while I brush on "Smoke Gray" water-based paint. I'm not going to paint the floor of the separator because I want to keep it slick. I will probably apply a heavy coat of paste wax to the tempered hardboard. The will provide some moisture protection while keeping friction losses down.
Don't you think the paste wax will get gummed up from the dust? I was thinking that with a coat of paint and then a lacquer topcoat, that would keep it slick enough. Hmm. Aren't we just overengineering this little number? ;D
i like the idea of the adj outlet pipe. im just wondering how you are gonna hold the pipe in test positions and still get it sealed. or are u just gonna use some rtv after u do some testing.
i was thinking of a large o-ring and a hose clamp or one of those spring loaded clamps
Quote from: dabullseye on August 30, 2011, 09:54:14 AM
i like the idea of the adj outlet pipe. im just wondering how you are gonna hold the pipe in test positions and still get it sealed. or are u just gonna use some rtv after u do some testing.
i was thinking of a large o-ring and a hose clamp or one of those spring loaded clamps
I'm plannning to use Mortite caulking cord. It is dirt cheap, easy to mold, will be air tight and can be removed easily. The Mortite will be used only during testing. Once I decide what works best, I will caulk the pipe with construction adhesive. If I must remove it I still can, but at that point it is pretty much permanent.
@Retired2 - I just wanted to let you know that I have finished my build from your design and plans and have tested it out. The performance was exactly as I had hoped for and even though I didn't permanently seal everything or attach the lexan securely or have the filter and lower bag attached. Basically I just hooked the motor up while it was on my bench. I took the hose and buried it in a bucket of fine dust and hardly anything came out. I can hardly wait to get it painted and permanently sealed up to see what it can do. I appreciate yours and everyone else's openness with your builds and info.
DonZ
Quote from: Don_Z on August 31, 2011, 05:40:05 PM
@Retired2 - I just wanted to let you know that I have finished my build from your design and plans and have tested it out. The performance was exactly as I had hoped for and even though I didn't permanently seal everything or attach the lexan securely or have the filter and lower bag attached. Basically I just hooked the motor up while it was on my bench. I took the hose and buried it in a bucket of fine dust and hardly anything came out. I can hardly wait to get it painted and permanently sealed up to see what it can do. I appreciate yours and everyone else's openness with your builds and info.
DonZ
Congratulations Don! Glad to hear it's working out. What's your early assessment of the bellmouth? Did you compare it to a straight pipe?
I knew I wasn't going to be first to complete the construction of this design (I'm quick with ideas, but slow on execution), but at least the positive report will give me the motivation I need to work harder on my own. If you had told me it didn't work worth a hoot, I might be in the shop cutting mine up for scrap.
Well, I did not use the bell-mouth, mine is on the way, but by using your top opening design, it will allow me to install it later. but the biggest advancements that I felt were a benefit was you inner ring rib cage and the hardwood supports at the ends that capped the lexan. Rather brilliant.
looking at your metal intake do u think it would have been better to extend it into the chamber and cut it off on the same cir. as the inside dia. im just wondering what kind of turbulence it is at that point from your test.
one other thing i see where you added a 3/16 t-rod. what do u think of just attaching the rod to the bottom of the can so that the baffle will just sag and rest on top of rod
Quote from: dabullseye on September 01, 2011, 08:45:57 AM
looking at your metal intake do u think it would have been better to extend it into the chamber and cut it off on the same cir. as the inside dia. im just wondering what kind of turbulence it is at that point from your test.
There is absolutely nothing to be gained by extending the metal intake of a rectangular intake port. A rectangular intake, if done like mine, is flush against the walls, ceiling, and floor of the separator, so the separator itself forms the intake port. All that would be accomplished by extending the metal port is to add the extra work of cutting the circular arc. And then you would just be covering separator material with a skin of metal, but the inlet would be still be exactly the same size and shape.
Now a circular intake port is a totally different story. There you want to cut the end with an arc that matches the separator because the intake is round and it does not match up to the walls, ceiling and floor of the separator the way a rectangular intake does.
Quote from: dabullseye on September 01, 2011, 08:52:36 AM
one other thing i see where you added a 3/16 t-rod. what do u think of just attaching the rod to the bottom of the can so that the baffle will just sag and rest on top of rod
It would work, but I don't want anything that complicates the task of pulling the drum and emptying it. I'm already working on a design that does not require me to disconnect any hoses or piping. The drum will drop down from the slot and then slide out to be emptied. The process will be reversed to put the drum back and seal it.
Well, I made a little progress in the past two days, but I also had some problems. Two things I would do different at this point: First, I would not use water base paint again - it takes forever and a day to harden (actually it never does). Use oil base and just throw the brush away! Secondly, I would not use plexiglass again, it cracks far to easily. Ironically, it can be bent in a very tight circle with no problems, but drill a hole in it and it becomes as fragile as glass. Next time, I will use polycarbonate. Here's some progress photos, I may have one or two more tomorrow evening.
In this photo I am using a slot cutter to cut a 1/8"w x 3/16"dp dado in the top and bottom plexiglass retainer rings. The slot will be used for sealing the plexiglass.
(https://www.dropbox.com/s/qu44asubhqw00nh/Separator-40.jpg?raw=1)
Here I'm inserting rope caulk into the dado to seal the plexiglass. I decided to use the rope caulk because it was the only thing I could think of that would stay put without running or dripping. The rope caulk is not an adhesive, so I will retain the plexiglass with screws.
(https://www.dropbox.com/s/3mz6bmv5fe08h7k/Separator-41.jpg?raw=1)
And here is where disaster struck - not one, but two vertical cracks. I was extremely careful not to cinch down the screws because I knew this can be a problem with acrylic. Interestingly, both cracks occured at a vertical rib. I soaked the crack with crazy glue and it seems to be holding, but if it gets worse, I'll be replacing the acrylic with polycarbonate (Lexan). Before I decided on truss head screws, I did some testing with countersunk holes - don't even think about it!
(https://www.dropbox.com/s/49ekd5lu8smt641/Separator-42.jpg?raw=1)
I used plexi or polycarbonate in mine. (it was laying around the shop and I don't recall which type it was)
My build was similar to yours in that both ends of the plastic are captive. The captive ends held the plastic in place. Therefore, I don't understand the need for screws. Did you use the screws simply to ensure that you had a good seal against the Moretite?
Steve
Quote from: Bulldog8 on September 03, 2011, 06:02:31 AM
I used plexi or polycarbonate in mine. (it was laying around the shop and I don't recall which type it was)
My build was similar to yours in that both ends of the plastic are captive. The captive ends held the plastic in place. Therefore, I don't understand the need for screws. Did you use the screws simply to ensure that you had a good seal against the Moretite?
Steve
Yes, the screws were added just to keep it sealed against the rope caulk. My thinking was that under vacuum it might flex enough to allow small air leaks. Maybe I should have just tested it without the screws because the plexiglass is really fit in very tight, and as you say it is held captive at both ends.
The cracking was an issue that I was having with mine as well. After the 3rd retry I used a clamping caul of the inside radius to slowly bent the acrylic into shape then very gently set the screws in by hand.
Quote from: Don_Z on September 03, 2011, 08:26:19 AM
The cracking was an issue that I was having with mine as well. After the 3rd retry I used a clamping caul of the inside radius to slowly bent the acrylic into shape then very gently set the screws in by hand.
This whole plexiglass/polycarbonate design is an area that needs more work by some great minds. It seems everyone is having their share of heartburn trying to make it work. When I set mine in place, I warmed it with my wife's hairdryer. That was plenty of heat to shape it and ease it nicely into place, but of course as I found out that's the easy part. Sealing and securing it is where it gets a little hairy.
One "off the wall" idea I have is to rout a rabbit in the plexiglass retaining rings just as I did, but not fill it with rope caulk. Then from the outside of the retaining rings drill holes radially into the rabbit every six inches or so. Then set the plexiglass in place, and make sure it is seated, clamp lightly if necessary. Then using some yet to be determined product that would act as both an adhesive and sealant, inject it into the radial holes and let it fill the rabbit from the outside.
O.K. folks, there's a challenge, go to work on that idea and give us a report!!!
A clear polyester would machine much easier, IMHO. And would be much less likely to crack/shatter where fastened with a screw. Problem is, all you can typically find in stores in acrylic ("Plexiglas") and polycarbonate. The polyester products fall between the two of these for durability. But the polyesters are very machinable and moldable.
Finally. Here's the photos of my completed separator.
This photo shows the rod I added to stabilize the baffle plate. It might have been O.K. without it, but I didn't think it would have any effect on the performance of the separator, so I installed it now.
(https://www.dropbox.com/s/ptoewqhan7x3xe0/Separator-43.jpg?raw=1)
And here's the finished product. I used rope caulk to seal the inlet pipe, and I will do the same with the outlet pipe. When I'm sure I won't be making any more changes, I will replace the rope caulk with something more permanent.
(https://www.dropbox.com/s/qxewlbidhy47cue/Separator-45.jpg?raw=1)
So, now you all expect to get some immediate test results. Wrong! I want to relish the belief that this thing is really going to work well for a while longer. Then I'll risk shattering that hope with real world testing. Actually, the real reason for the delay is pictured below. (See later post for video of test). I need to raise the DC up on a fixed support and then finish the piping system.
(https://www.dropbox.com/s/5nnr853jzsida3k/Separator-46.jpg?raw=1)
When setting the screws, I chose to countersink them to reduce any turbulence and used a #4 1/2" flat head with a fine thread. When working with acrylic, you just have to remind yourself that it still is a very brittle material and you cannot torque fasteners into it like normal and that you have to ease them into place. If you see it flex, you are going to hard and it will fail. On my first attempt at a separator I tried the whole dado slot for the plexi, and it a real pain in the rear to get it in place if you are wanting to get it in there tight.
FIRST TEST VIDEO
O.K. Guys, I couldn't stand it any longer so I did a quick and dirty hook-up of my new bellmouthed outlet, rectangular inlet separator to see what happens. All I can say is the preliminary results look very promising, but the jury is still out. I don't want to speculate on the improvement the bellmouth makes, but the good news is it certainly hasn't hurt. I think it might be safe to say a rectangular (taller than wide) inlet is the way to go - it puts the dirt immediately against the outside wall and over the drop slot, and there seems to be less turbulance where the two airstreams converge.
When I complete the modifications to my DC support and eliminate much of the flex hose, I will do more extensive testing using an ammeter. I'm hoping the ammeter will tell me something about the performance of the bellmouth outlet versus a straight pipe. I'm also hoping it will give me some idea how much loss the separator is introducing.
So, here for your enjoyment is a video of my first test. I apologize for any quality problems because I was holding the camera with one hand and feeding dirt with the other. The dirt being fed in is pine shavings from my thickness planer. My guess is this material is one of the easiest for the separator to handle, but not a single chip by-passed the separator. That's great news because my worst fear was the bellmouth would upset the internal dynamics for some reason and allow a lot of dirt to bypass the separator. I didn't use pine chips to bias the results, it is just what I had on hand.
Give the file a minute, it is big.
https://www.dropbox.com/s/n6x7xrekgf2l33y/Separator.MPG?dl=0 (https://www.dropbox.com/s/n6x7xrekgf2l33y/Separator.MPG?dl=0)
Sweet! :o I tested mine having nothing hooked up but the motor and threw handfuls of fine mdf dust and nothing came out the other side, the separator worked like a champ. Unfortunately I am going to have to hold off on giving it the paint job I wanted until after I get the wife her new kitchen (that I put on hold while I made this thing.) After all, orders are orders.) I think when I do paint it, I will repaint my other equipment as well as I am going to be cutting 5" ports all of them. Maybe a nice flame job or something hot roddish. 8)
Very nice work. Looks like you have a winner there.
Quote from: Don_Z on September 03, 2011, 02:57:31 PM
Unfortunately I am going to have to hold off on giving it the paint job I wanted until after I get the wife her new kitchen (that I put on hold while I made this thing.) After all, orders are orders.) I think when I do paint it, I will repaint my other equipment as well as I am going to be cutting 5" ports all of them. Maybe a nice flame job or something hot roddish. 8)
Don, I'm no expert on separators, but I'd be willing to bet they work as good without paint as they do with it. :)
Quote from: phil (admin) on September 03, 2011, 04:03:39 PM
Very nice work. Looks like you have a winner there.
Thanks for the compliment Phil, but you are the one that provided the rest of us with a solid design for a truly innovative idea - we're just monkeying around with tweaks.
very nice . i cant wait till mine is finished
Retired2... I also have a 50-760 collector that I am designing a TopHat for and I really like your design which I will use as much of as possible. One of the biggest issues with the seperator is knowing when the can is full and then emptying it (I've had a DC seperator since 2008 and I always have to disconnect the hoses and remove the can). I installed a CanFull window after over filling it a few times
With the TopHat configuration I was planning to attach the TopHat directly to the under side of the 760 with the 760 inlet going directly into the top of the TopHat (making it part of the 760). I will set my can on a platform that can be reaised and locked to mount the can to the TopHat. To empty the can I just lower it and slide it out. This will allow me to use a larger can and not have to connect/disconnect any hoses.
The only design required to impliment this approch would be the platform raising/lowering and locking mechanism. It could be very simple, a couple blocks of wood and a wedge under the can or more complex platform design with a mechanical lift assembly.
Have you had any thoughts along this line.?
Ron
Quote from: RonS on September 04, 2011, 12:39:42 PM
Retired2... I also have a 50-760 collector that I am designing a TopHat for and I really like your design which I will use as much of as possible. One of the biggest issues with the seperator is knowing when the can is full and then emptying it (I've had a DC seperator since 2008 and I always have to disconnect the hoses and remove the can). I installed a CanFull window after over filling it a few times
With the TopHat configuration I was planning to attach the TopHat directly to the under side of the 760 with the 760 inlet going directly into the top of the TopHat (making it part of the 760). I will set my can on a platform that can be reaised and locked to mount the can to the TopHat. To empty the can I just lower it and slide it out. This will allow me to use a larger can and not have to connect/disconnect any hoses.
The only design required to impliment this approch would be the platform raising/lowering and locking mechanism. It could be very simple, a couple blocks of wood and a wedge under the can or more complex platform design with a mechanical lift assembly.
Have you had any thoughts along this line.?
Ron
Ron, the short answer is I have been thinking about this a lot, and I plan to do pretty much exactly what you described. However, the devil is in the details, or in this case the jacking mechanism. I started cutting wood today for the fixed support that will replace the wheeled cart on my 50-760. I would like to raise the DC about a foot. I have plenty of headroom in my shop, but I need more headroom under the DC for the Bute container and top hat separator.
I was going to put the separator up against the bottom of the DC, but the diameter of my separator is too big to do that, so it will have to be suspended several inches. It will probably be suspended on threaded rods. That will allow me to remove it or adjust it, but it is not intended to be removed to empty the drum.
So, I'm proceeding without a design in mind for the jacking device, but my initial thoughts were some kind of large wedge that is pushed in from one side causing a table to move up. That will probably require some waxed guides and slots to work properly, so I'm trying to come up with something simpler. The jacking device can't be too sloppy or it may compromise the seal at the top of the drum.
I'll be posting some photos here as I make some progress, but for the moment my objective is to just get the DC raised so I can do futher testing of the bellmouth outlet. That means it will be a while before I solve the lifting device problem.
Don't waste your time on jacking mechanisms etc. if you are planing to use a short piece of flex hose to join the top hat to the DC. You just need an inch or so of stretch/compression in the flex hose to slip the pail in and out, and the flex hose is plenty strong enough to support the top hat suspended by the flex hose. No need to undo any clamps.
Quote from: Rick T on September 04, 2011, 06:02:45 PM
Don't waste your time on jacking mechanisms etc. if you are planing to use a short piece of flex hose to join the top hat to the DC. You just need an inch or so of stretch/compression in the flex hose to slip the pail in and out, and the flex hose is plenty strong enough to support the top hat suspended by the flex hose. No need to undo any clamps.
You may be right Rick, but I will have a very short (an inch or two) flex hose connection on the inlet pipe also. That will keep me restrained in the vertical plane, so I'm not sure I will be able to lift the separator with nearly a hard connection there. I could remove the long radius elbow that meets up with the inlet nozzle and replace it with flex hose, but I'm not crazy about that idea.
Guys, take every thought that follows to be purely speculation, and not in any way tried and true. I have gathered all of the necessary materials to make my own top hat style separator from a Grizzly 2 hp 1029, but have yet to begin the build. So far I have the Wynn nano cartridge filter, a strip of .093 PETG plastic for the top hat (same mat'l ClearVue uses for their cyclones) and the scrap sheet goods to build a new platform and frame for all of the components.
I too have been wrestling with how to best keep the top hat stationary to minimize any turbulence issues associated with using ribbed flex, but wanting the bottom Brute container to be easy remove and empty. Two untried approaches I am considering so far, both would rest the chip container on a "loose" platform of plywood resting on top of the wheeled cart. One thought was to make a lever operated "cam" rod out of something like 3/4" conduit and shaped wooden blocks to raise the loose plywood platform against the fixed top hat. If it worked it would be really slick, but it seemed I might be experimenting with the shape of the cam blocks for awhile before I got them right.
The second thought was to just sink a couple screw eyes up high on the outside of the plywood uprights and run a simple ratchet strap under the loose plywood platform. All I would need to do is crank the ratchet strap lever a couple of times to snug the loose plywood platform and chip barrel up against the fixed top hat separator. This method would require essentially no fabrication or trial and error. I think I will end up trying this out first, as it appeals to my lazy side...
Given, that finding the time to make the parts for the separator is proving challenging to me, I have no doubt that one of you will find a way to do this long before I am able to experiment with the best method myself... but I thought I'd throw the ideas out there in the meantime. If I get a chance tomorrow, I'll see if I can sketch my ideas up and post them here.
Quote from: JeffQ on September 04, 2011, 07:22:34 PM
Guys, take every thought that follows to be purely speculation, and not in any way tried and true. I have gathered all of the necessary materials to make my own top hat style separator from a Grizzly 2 hp 1029, but have yet to begin the build. So far I have the Wynn nano cartridge filter, a strip of .093 PETG plastic for the top hat (same mat'l ClearVue uses for their cyclones) and the scrap sheet goods to build a new platform and frame for all of the components.
I too have been wrestling with how to best keep the top hat stationary to minimize any turbulence issues associated with using ribbed flex, but wanting the bottom Brute container to be easy remove and empty. Two untried approaches I am considering so far, both would rest the chip container on a "loose" platform of plywood resting on top of the wheeled cart. One thought was to make a lever operated "cam" rod out of something like 3/4" conduit and shaped wooden blocks to raise the loose plywood platform against the fixed top hat. If it worked it would be really slick, but it seemed I might be experimenting with the shape of the cam blocks for awhile before I got them right.
The second thought was to just sink a couple screw eyes up high on the outside of the plywood uprights and run a simple ratchet strap under the loose plywood platform. All I would need to do is crank the ratchet strap lever a couple of times to snug the loose plywood platform and chip barrel up against the fixed top hat separator. This method would require essentially no fabrication or trial and error. I think I will end up trying this out first, as it appeals to my lazy side...
Given, that finding the time to make the parts for the separator is proving challenging to me, I have no doubt that one of you will find a way to do this long before I am able to experiment with the best method myself... but I thought I'd throw the ideas out there in the meantime. If I get a chance tomorrow, I'll see if I can sketch my ideas up and post them here.
Those are some good ideas, but I can't use a cart. Another idea I had was a platform supported by springs that could carry the load of a full can of waste, but could be depressed with a cam lever or Destaco clamp in order to free the drum.
whichever method you use, when the DC runs, it needs to be able to form an air-tight seal between the collection pail and bottom plate of the top hat.
well i added a 1/2 x 3/8 to bottom plate to get a better seal on trash can
this is upside down and the standoff need a little trimming
the one stick is just a kicker to hold it up
this is my plastic. so far things are going good just need to do some sanding to smooth out some router marks and make the wood blocks that trap the plastic.
i cant wait till its finished. i tried to do all the pic in one post but it telling me it was to large each pic is just over a MB
now that i got these pic up i see where it says each pic is over a KB im confused
I usually use a photo editor to downsize my files to approx 1000 x 700 pixels - that's still a pretty nice size for web viewing. And, you can usually keep the file size smaller by choosing a stronger jpeg compression. For webposting, you can't see the difference in image quality.
I think the way photo images work on this forum is you can upload them as attachments as you did, but then you will be size limited. If you host your own photos as I do, you are merely uploading the link to the computer where they are stored, so then you are not size limited. I use Dropbox. I think the first 20 gb are free. It's easy to use and it has some other benefits if you choose to take advantage of them.
By the way, your build looks really good. If I had it to do over, I would have added an extra ring on the bottom to make the drum seal a little deeper also, so that is a good upgrade.
Here is the added ring and it fits great since I glued it in place while it was on the can sometimes I surprise myself.
TEST DATA
Well, the construction of my dust collector stand is far enough along that today I was able to do some ammeter testing. I took meter readings for both a bellmouth outlet pipe and a straight outlet pipe. I also took a set of readings with the separator removed.
The data table shows ammeter and sound level readings for three positions of each pipe. The positions represent the distance down from top inside of the separator to the bottom of the outlet pipe. I took readings at three locations just to see if the ammeter could pick up a difference, not to prove or disprove where the sweetspot of separation occurs. I?m assuming that to be close to the 3? position.
At each position, I then took four readings for different conditions. ?Deadhead? means the DC was running with no blast gates open. The ?Floorsweep? is a moderate distance from my DC and has a 5? open port. The ?Bandsaw? is my longest connection with a 4? and 2? port. And ?Open? readings were taken with the 5? end cap shown in the photo removed. That is a distance of about 3 feet of pipe and one 90 degree elbow from the separator.
Here?s the photo showing my test setup. It's 5" taller than it was supposed to be - early-stage dementia!!! :):
(https://www.dropbox.com/s/4pf4zcs1i233cz7/Separator-47.jpg?raw=1)
And here's the data table with the ampere and sound level readings:
(https://www.dropbox.com/s/q5zuc5zdmlgy7ll/DataChart-1.jpg?raw=1)
Here are the problems I found with ammeter readings:
- Meter readings fall in a tight range making data analysis difficult.
- The min reading (deadheaded) and max reading (open at DC) range is only 2.36 amps.
- The operational range (Floorsweep and Bandsaw) of this test is only 0.78 amps.
- Readings bounce by 0.10 during the test.
- Readings drift down slightly during a sustained test - not sure why. Motor temperature?
So, what can we conclude from this data? Well, it seems to provide more evidence that a bellmouth outlet pipe enhances the performance of a Thien separator. It may look like a very small increase, but you need to keep in mind the small range of test readings. But, without additional test equipment it is difficult to quantify the improvement in more meaningful numbers.
I did make some other observations from the data:
1) I would have expected the "Deadheaded" readings to all be the same, but for some reason the bellmouth readings are higher which would suggest it is moving more air. I doubt that is the case, since the only air could come from minute leaks. I am thinking it might be the result of the separator being close coupled to the DC and the fan may be doing more work as a result of turbulence.
2) Correction: The bellmouth pipe seemed to move less air when it was in the up (1-1/2") position, but it performed better in both of the other two positions. Conversely, the straight pipe performed its best in the up position, and slightly weaker in the other two positions. In no case did the straight pipe produce higher readings than the bellmouth.
3) The normal operating load readings (floorsweep and bandsaw) are higher for the bellmouth pipe (middle and low positions only) than for no separator at all. That makes no sense whatsover, unless there is a base-load resulting from separator turbulance as I suggested in item 1.
4) The sound level readings mean nothing other than I was looking to see if some conditions might be noisier than others. As it turned out they are all pretty close other than Deadheaded which is much quieter due to the lack of high velocity air.
And just to add to the confusion, here's a little gem from a Cincinnatti Fan engineering document:
Duct Inlet Spin
"A major cause of reduced fan performance is an inlet duct connection that produces a spin or pre-rotation of the air entering the fan inlet. Inlet spin in the same direction of the fan wheel will reduce air volume and pressure ratings. Inlet spin in the opposite direction of the fan rotation will substantially increase the motor horsepower requirements. An ideal inlet condition is one which allows the air to enter the fan axially and evenly without spin in either direction."
I wonder whether rotation might be a factor in a close-coupled top hat design with a bellmouthed pick-up?
Regards, and enjoy the data,
Retired2
Okay, just so that I am reading this correctly, you are saying that the inlet (bellmouth) pipe performed better being placed more than halfway inside the separator and that the bellmouth does perform better than a straight pipe?? By the way, a very solid build. I just finished mine up yesterday alas no time for painting it just yet. She isn't the prettiest girl at the dance but she has some nice moves. Pictures to come later today.
Quote from: Don_Z on September 08, 2011, 06:56:05 AM
Okay, just so that I am reading this correctly, you are saying that the inlet (bellmouth) pipe performed better being placed more than halfway inside the separator and that the bellmouth does perform better than a straight pipe?? By the way, a very solid build. I just finished mine up yesterday alas no time for painting it just yet. She isn't the prettiest girl at the dance but she has some nice moves. Pictures to come later today.
Don, I don't want to make any bold claims because it has already been suggested by one member of this forum that my only qualificatons are having slept at a Holiday Inn Express and that I should be banned from posting.
So, with that in mind, and considering the problems I've outlined above for ammeter readings, I can say the readings I took show the blower was doing more work when the bellmouth was at the mid and lower position (deeper in the chamber). and that in all cases the ammeter readings were slightly higher for the bellmouth than the straight pipe. Normally, higher readings indicate the blower is moving more air.
p.s. Don, don't paint anything with waterbased paint that you hope to get apart in the future. The plug I made to get the bellmouth out of my chamber was only screwed in place one day and I had to pry it loose with a 1" butt chisel.
Well I have always been a person that thinks the proof is in the pudding. And whoever it was that said that regarding your work and approach I would invite to see their work and see what they can produce rather than hot air and derogatory remarks against someone when this is supposed to be an open forum to help each other. I bet that was what Phil had in mind when he made this forum but I am not going to talk for him.
Anyway, the reason I am asking is because I have ordered my bellmouth pipe and have built my system around a 5" pipe/ hose assembly. The interior of my chamber is 5.75", so I am asking your opinion on how far should I place the bottom of the bellmouth opening from the top of the chamber (not trying to get your to refute or challenge anyone else's claims) since you are the only person I have seen use this kind of pipe?
And thanks for the warning on the paint. I never use waterbased products anyway. They just don't produce those fumes that make me feel all warm and fuzzy. :o
Quote from: Don_Z on September 08, 2011, 09:25:19 AM
Anyway, the reason I am asking is because I have ordered my bellmouth pipe and have built my system around a 5" pipe/ hose assembly. The interior of my chamber is 5.75", so I am asking your opinion on how far should I place the bottom of the bellmouth opening from the top of the chamber (not trying to get your to refute or challenge anyone else's claims) since you are the only person I have seen use this kind of pipe?
And thanks for the warning on the paint. I never use waterbased products anyway. They just don't produce those fumes that make me feel all warm and fuzzy. :o
Well Don, let me put it this way. The bellmouth is staying in my separator until someone now provides evidence to the contrary. I'm convinced there is some benefit - I just don't know how much.
And by the way, I am equally convinced that the rectangular inlet is also beneficial, but again I can't say by how much. What I'm not sure of is whether a custom fabricated transition from 5" round to rectangular like mine is necessary. I think it is possible to fashion one from wood that would provide most of the benefits at a much lower cost.
Quote from: retired2 on September 08, 2011, 09:36:21 AM
Quote from: Don_Z on September 08, 2011, 09:25:19 AM
Anyway, the reason I am asking is because I have ordered my bellmouth pipe and have built my system around a 5" pipe/ hose assembly. The interior of my chamber is 5.75", so I am asking your opinion on how far should I place the bottom of the bellmouth opening from the top of the chamber (not trying to get your to refute or challenge anyone else's claims) since you are the only person I have seen use this kind of pipe?
And thanks for the warning on the paint. I never use waterbased products anyway. They just don't produce those fumes that make me feel all warm and fuzzy. :o
Well, Don let me put it this way. The bellmouth is staying in my separator until someone now provides evidence to the contrary. I'm convinced there is some benefit - I just don't know how much.
And by the way, I am equally convinced that the rectangular inlet is also beneficial, but again I can't say by how much. What I'm not sure of is whether a custom fabricated transition from 5" round to rectangular like mine is necessary. I think it is possible to fashion one from wood that would provide nearly all the benefit.
Don, I see I didn't answer your question about where I think the bellmouth should be positioned. My chamber is 5-7/8" deep, very close to yours, and I intend to start out with it 3" down from the top. I don't intend to do any formal testing at various positions, but I will be watching for signs that stuff is by-passing. Then I'll try a different position to see if it works better. I have a feeling the 3" location is very close, if not exactly at the sweetspot.
Before I started the ampere tests, I cleaned my filter bag. Boy, did the DC get loud after that. So, now I am going to start working on noise abatement.
I think it would be rather easy to frame up a wall with a door and then soundproof it with insulation around that little nook where you have it placed now.
Quote from: Don_Z on September 08, 2011, 05:19:13 PM
I think it would be rather easy to frame up a wall with a door and then soundproof it with insulation around that little nook where you have it placed now.
The framing is piled up on my workbench and the solid core door is sitting in a corner. Even the wall and door locations are marked out on the floor. I'd like to start immediately, but I want to be sure I'm done messing with the stand.
I really don't want to disconnect hoses to empty the waste drum, so I'm planning to suspend the top hat from the framing above. It will be locked in place. Then the drum will be lowered to empty it and then raised up against the separator to seal it. Sounds great, but I haven't figured out an easy way to do it. I've been thinking about either a wedge or cam lifting mechanizm.
ANOTHER INFORMAL TEST
This evening I threw a bunch of mixed dirt at the separator via my floor sweep. It was a combination of fines from my radial arm saw and shavings from my thickness planer. I don't have any sanding dirt to try, but everything went into the drum and nothing bypassed to the DC plastic bag. It was a thing of beauty to watch. The only thing I noticed is the finer dirt seems to make more revolutions before it all drops out. The shavings seem to drop much faster.
THE CASE FOR A "TWEAKED" RECTANGULAR INLET
When I was framing my rectangular inlet port, I made a small construction tweak that I failed to point out. The amount of the tweak is dimensionally small enough that it is difficult to see in the construction photos I posted.
As Phil has often pointed out, the Thien separator depends on a fast, smooth, centrifigal air stream for optimum performance. Since air in the separation chamber makes more than one complete revolution, it must converge with incoming air. The design of the inlet port will determine how smoothly the two air streams converge.
Below is a sketch that illustrates the benefit of a rectangular inlet and the tweak I made. The sketch is not to scale and it is slightly exaggerated to illustrate the differences between the three inlet possibilities.
(https://www.dropbox.com/s/9l5slkqoy0ehjvc/Rectangular%20Inlet.jpg?raw=1)
The green lines (A) show a wider, typically round inlet port. The green tangent line (A) shows that the recirculating air will converge with incoming air, and the far wall of the separator, at a more obtuse angle. This will create more turbulance.
The red lines (B) represent a narrower rectangular inlet. As you can see the tangent line, and the angle of convergence, is becoming more acute and therefore smoother.
The black lines (C) represent the small tweak I made. When I faced glued the maple to frame my inlet port and capture the ends of the plexiglass (see my construction photos), I brought the curvature of the inlet framing slightly inside the circular circumference. It was only about 1/8", but it has the effect shown by the tangent line (C). It is slightly more acute and hopefully, the smoothest of the three examples. In some very small way, this tweak may accomplish some of the benefits of the "scroll" design.
Caution: More is not always better, so overdoing my tweak could cause a "ski lift" turbulance.
You need to get that Wynn filter on that bad boy!
Nice test write up. Concerning the blower inlet spin issue (since it is not really a problem), you could steal a handful of straws from McD's, cut them in half, pack them into your bell mouth, and set them in place with superglue. And if the blower doesn't immediately rip them out and shred them (probably not covered in the warranty) then you can see if there is more air resistance due to the straws that you lose to the inlet spin. I doubt there would be a significant gain.
Oh and to other readers who are wondering about my sanity, I did not pull the straws out of my @55, test wind tunnels usually have a honeycomb panel before the test section to linearize the flow. Straws are cheaper! All may doubt my sanity when I post pictures for my 3gal bucket prototype I just built for 99 cents. I'l save that for a different thread...
Here's what Bill Pentz has to say about the spinning air inside the cyclone vrs the spin of the impeller. This may not make a big differance in a basic Thien Seperator but could have some effect in a TopHat design, where the spin inside the tophat is counter to the spin of the impeller.
From Bill Pentz's website. (link below)
If the spinning air inside the cyclone hits the blower impeller going the wrong way, then the motor must do lots of extra work to reverse that spin and we lose considerable airflow. We need to make sure our cyclone, motor and impeller spins match! I prefer to build either a left or right hand cyclone to best match the shop in which it gets installed. We can easily figure out which way the air spins in our cyclone. The airflow coming into the cyclone will spin in the same direction that the inlet starts it. The air in my cyclone design spirals down then goes up without changing direction of spin. So a left hand cyclone will have its inlet coming out the back left of the cyclone which means we get a clockwise airflow. Most build left hand cyclones because that airflow matches most available impellers and reversed impellers are expensive and hard to find. If the inlet is located on the back right of the cyclone then the airflow inside is counterclockwise and we have a right hand cyclone. Both right and left separate equally well, but only if you match the motor, impeller and cyclone airflows.
http://billpentz.com/woodworking/cyclone/BuildCyclone.cfm
Ron
Quote from: RonS on September 09, 2011, 08:17:44 PM
Here's what Bill Pentz has to say about the spinning air inside the cyclone vrs the spin of the impeller. This may not make a big differance in a basic Thien Seperator but could have some effect in a TopHat design, where the spin inside the tophat is counter to the spin of the impeller.
Ron
Ron,
My separator rotation is opposite the blower rotation, and I worried about that a little, especially since no one had experience with a bellmouth outlet. I suppose if I were to build a mirror image separator, the ammeter might tell me if air rotation was affecting performance. However, I don't have the energy or patience to do that right now. Sorry, "plauale", I'm not up to trying the McD's straw test either.
One of the observations I noted from my ampere test was that the readings were lower with the separator removed than with the bellmouth installed. I expected them to be higher. I don't have an explanation for that, but it makes an argument that air rotation is not an issue.
Due to the air coming in from the separator chamber to the outlet pipe and to the impeller being such a short distance I feel there is not enough of a span to allow it to spin at all. Also, with regards to the difference between a cyclone vs a top hat separator, is that the cyclone uses the entire chamber and impeller to achieve its separation vortex while the top hat uses the separator chamber to achieve its separation vortex BEFORE it reaches the impeller and WITHOUT direction of the impeller. I thought of that issue before I began my build and designed accordingly, but the video of Retired2's build shows it works just as well as if it were built the other way. I feel that the utterances of bill pentz should be regarded as extreme overkill and a shameless point of his self promotion/ego/marketing campaign that unless we do just as he says and buy the products (clearvue, ect.) that he endorses, then we are all going to die a horrible and painful death with our lungs jammed full of sawdust. If you want to sell me a product, fine. But I do not give into scare tactic sales pitches. ;D
Separator Update:
Noise:
I recall at least one person commenting that their DC didn't seem as noisy after they installed their separator. That is not the case with mine. The increased noise is a low frequency rumble. The source seems to be my baffle and stiffener plate, and possibly the Brute drum. When I turn the separator over and tap on the center of the baffle, it really seems to be "tuned" like a drum.
If I were rebuilding my separator, I would do what Don_Z did, i.e. a full thick bottom that is routed back from the baffle edge. That would accomplish several things. It maintains a thin drop slot edge, it eliminates the need for a support rod in the separator cavity, and it stiffens and possibly dampens the rumble from the baffle.
I think the plastic walls of the Brute drum may also contribute to the noise. At the very least the light weight of the walls does not do a very good job of containing the noise. I suspect the plexiglass walls also allow a lot more noise to escape than the heavy-walled designs. Separator noise makes a good argument for using heavier stock for construction. I think even a thin top plate could add to the low frequency noise.
I have mis-diagnosed the source of this noise. See the update to this discussion in Post #92.
Paint:
I can't emphasize enough how bad the decision to use water-based paint was. I have a very dry shop and I allowed the paint to dry for days before putting it into service, but it never seems to harden the way an oil based finish does. The plug top that allows me to remove the bellmouth for testing has to be removed with a butt-chisel everytime because the painted surfaces continue to stick together weeks after the paint was applied.
Plexiglass:
Sexy, but a really bad choice. It cracks too easily and this makes it difficult to secure and seal. The coefficient of expansion must be very high because when I first cut it to length, it fit perfectly. After I heated it slightly with a hair dryer to ease it into shape the length grew by at least 1/8" so that it would no longer fit. After a short cool-down time, it fit perfectly again. So, I am not sure what the temperature swings in my shop are going to do to the seal.
And with regard to seal, I did a smoke test of an area that looked a little suspicious and sure enough there was a small leak. I have a feeling this is the result of the flexing that occurs from the on/off cycling of the DC, and possibly thermal expansion. So, now I am going to do what I didn't want to do in the first place, i.e. caulk all the exterior edges everywhere plexiglass meets wood.
just a thought but try 2 layers of wax paper under your top
Quote from: dabullseye on September 15, 2011, 09:06:46 AM
just a thought but try 2 layers of wax paper under your top
That might work. I'll give it a try, but I'm almost to the point where I don't expect to have much need to pull the top off.
Thanks
Quote from: retired2 on September 15, 2011, 10:00:35 AM
Quote from: dabullseye on September 15, 2011, 09:06:46 AM
just a thought but try 2 layers of wax paper under your top
That might work. I'll give it a try, but I'm almost to the point where I don't expect to have much need to pull the top off.
Thanks
Wait, what is the wax paper for?
I was thinking that two layers so that if eighter the top cap or the removable bellmouth cap were to stick to the paper that they would not stick to each other :)
Quote from: dabullseye on September 15, 2011, 08:09:47 PM
I was thinking that two layers so that if eighter the top cap or the removable bellmouth cap were to stick to the paper that they would not stick to each other :)
Oh! I get it. :)
ok ive been thinking about a seal for the outlet pipe. im thinking about getting section of old inner-tube and cutting out a 1/2 the diamaller hole it and screw it down with a chunk of mdf or plywood and maybe using a hose clamp on the rubber. mabe if i could find a small inner-tube i could just cut it in half lengthwise and hope the valve stem dont cause to much problems
Quote from: dabullseye on September 18, 2011, 11:25:10 PM
ok ive been thinking about a seal for the outlet pipe. im thinking about getting section of old inner-tube and cutting out a 1/2 the diamaller hole it and screw it down with a chunk of mdf or plywood and maybe using a hose clamp on the rubber. mabe if i could find a small inner-tube i could just cut it in half lengthwise and hope the valve stem dont cause to much problems
If you are considering the inner-tube and hose clamp seal as a means of keeping the outlet pipe adjustable or removable, it might be worth the trouble. However, once testing is complete I don't see the need for that flexibility, and at that point I will be making my outlet pipe permanent. I plan to attach it exactly the same way I did my floor sweep.
Here's a photo of the floor sweep showing a second collar around the outlet pipe to maintain vertical stability. Before installing the snap-lock pipe I wiped a thin layer of Locktite PL Premium Polyurethane Construction Adhesive on the end of the pipe and the inside surfaces of the floor sweep and collar. I wiped off the excess and allowed it to dry overnight. Then I came back the next day and put a heavy bead of caulk around the collar and pipe. I smoothed it with my finger, and allowed it plenty of time to dry. Then it was painted (with oil based enamel).
(https://www.dropbox.com/s/98a0b290o6jkftq/FloorSweep.jpg?raw=1)
How did you connect the bellmouth to the pipe?
Quote from: Don_Z on September 24, 2011, 11:24:41 AM
How did you connect the bellmouth to the pipe?
Don,
My bellmouth tapers slightly at the neck. That made it very easy to slip a piece of snap lock pipe over the end (see the first photo below). Then I put a board over the end of the pipe and tapped on it until the pipe was snug enough that I could pick the assembly up without the bellmouth falling off.
Initially, I planned to just use 3 equally spaced self-tapping duct screws to lock them together. However when I looked inside the pipe there was an 1/8" gap at the top end of the bellmouth (due to the taper). So, only the very end of the snaplock pipe was gripping the bellmouth. I decided the screws would hold it together fine, but I would surely have air leaks unless I applied silicone caulk to either the inside, the outside, or both.
At that point I decided to skip the screws, and the silicone, and use Lab-metal to fill the interior gap. Lab-metal seems to be a high tech (and high priced) body-filler that I use to smooth the inside of wye joints. The second photo shows the Lab-metal worked into the gap around the bellmouth neck, and then smoothed with my finger. The gap was large enough that the Lab-metal filler was sufficient to make it structurally sound and air tight.
(https://www.dropbox.com/s/fckb22la83bcuic/Bellmouth-04.jpg?raw=1)
(https://www.dropbox.com/s/zt28upy94fyurt3/BellmouthAttachment-02.jpg?raw=1)
That's good enough for me. Thanks :)
WASTE DRUM LIFT TABLE
I am making a little progress on the lift table I am building to eliminate the need for disconecting hoses in order to empty the waste drum. I considered a number of different mechanisms, but in the end I decided on axle-mounted wooden cam's.
In this first picture you see the four cams sandwiched together. They are glued together with a paper joint. One tap with a chisel and they are separated. You can see the cams are shaped to provide 1" of lift in 270 degrees of rotation.
(https://www.dropbox.com/s/i4an3m08lzrfrq7/Lift1.jpg?raw=1)
This is a photo of the lift assembly. The cams are mounted on axels of 3/8" threaded rod. Where the axel passes through the wooden frame there is a hub made of 1/2" steel tubing. The tubing is hidden in the photo by the washers and double nuts. The cams look a little darker because they have been given a good coat of paste wax.
(https://www.dropbox.com/s/kkjxjc6lrabx3wc/Lift2.jpg?raw=1)
Here the lift assembly has been installed in the DC stand, and 4 pairs of UHMW Polyethelyne guides have been added to keep the lift table moving in a vertical path. Notice that the cams have been turned in opposing directions. That means one axel will have to be turned clockwise while the other is turned counter-clockwise. The objective is to eliminate lateral forces during the lifting action.
(https://www.dropbox.com/s/rhe1g0vz7zv65v3/Lift4.jpg?raw=1)
Here's a picture of the top side of the lift table. The routed out donut matches the bottom of my Brute waste drum. This depession centers the drum so that it aligns with the separator which will be suspended from above.
(https://www.dropbox.com/s/03wilpk1ea7bplj/Lift5.jpg?raw=1)
The is the bottom side of the lift table. You can see the male half of the vertical guide strips. Also, you can see four rub strips of the same material where the cams will contact the table.
(https://www.dropbox.com/s/3p98oc3suzs57k6/Lift6.jpg?raw=1)
And finally, here's a photo of the table installed in the lift assembly. I need to build or buy two handles to attach to the end of the axels for operation, but I gave it a quick try with a wrench and it works like a charm (but I didn't try it with a full drum yet).
(https://www.dropbox.com/s/k8pzy8yvn0g7s9t/Lift7.jpg?raw=1)
Well, that is as far as I have progressed. The next step is to suspend the separator from the DC frame. It is little more complicated than just hanging it with some threaded rod. If the separator is fixed with no movement, then the cams would require a locking mechanism to hold the drum up against the fixed position of the separator and to maintain a good seal. I decided a locking mechanism was a complication I could do without. So, I designed the cams with a slight amount of overtravel. When they reach the 270 degree mark the table lands on a flat on the cam. The flat is wide enough so that the position is maintained without any locking device.
However, with this arrangement, the separator must move up slightly to absorb the cam overtravel. It must also maintain a slight downward pressure to ensure a good seal with the drum. So, the threaded suspension rods will have to be spring-loaded at one end. I don't think it is going to be very complicated.
Keep watching this space for updates and photos. I will post them as soon as the work is completed.
FINAL PHOTOS
Here's the final photos of the waste drum lift mechanism. The first photo shows the lift table in the up position and the drum engaged with the separator. You can also see I have not finished the levers for turning the axles. The second photo shows the spring-loaded suspension rods. The springs can be adjusted to increase of decrease the downward loading.
(https://www.dropbox.com/s/kf95kotnka60cqr/Lift8.jpg?raw=1)
(https://www.dropbox.com/s/xumvq5m1aenhq5n/Lift9.jpg?raw=1)
So, how does it work? Well, a lot better than disconnecting hoses to empty the drum, but not quite as good as I had hoped. The problem is getting the top rim of the drum to line up with the receiving dado on the bottom of the separator. There are two issues:
The first is that the top of the drum is not concentric with the bottom (I should have expected that), so my centering donut was centering the bottom, but not the top. I was able to correct this problem by moving the separator slightly off center, and then marking the drum so that it is always installed in the same rotation.
The second problem is the cams must be rotated equally or the drum will raise with a slight tilt and miss the dado. This just requires keeping an eye on the top of the drum as the table is being raised.
Both of these issues could be improved by adding a heavy chamfer to both sides of the receiving dado on the separator. That would require cutting the dado deeper or adding another ring with chamfers to the existing dado. Unfortuantely, that extra depth would require replacing the cams with new ones that have a higher lift.
humm i thought u said u would never use mdf again
Quote from: dabullseye on September 24, 2011, 08:12:27 PM
humm i thought u said u would never use mdf again
Actually, what I said was "Remind me never to use MDF again." No one called! :)
The problem is I still have some of it on hand, so I will probably keep burying myself in silt until it is gone.
I used JB weld Putty and was able to connect it to the pipe. I then repositioned the pupe so that the bottom of the bellmouth was 3" from the top. It works fine, but I am still getting just a little bypass.
Quote from: Don_Z on September 25, 2011, 09:41:51 AM
I used JB weld Putty and was able to connect it to the pipe. I then repositioned the pupe so that the bottom of the bellmouth was 3" from the top. It works fine, but I am still getting just a little bypass.
Don, in all my posts I have been stating the position of the bellmouth as measured from the top inside of the separator. It just made it easy to mark dimensions on the exit pipe. However, the distance from the baffle is a much more relevant reference point. So, for what it is worth, my bellmouth is now 2-1/8" above the baffle. It was 2-7/8", but I changed it for testing. I can't see any difference in performance between the two.
As I recall, your build is very similar to mine, but I am getting no by-pass. Maybe your problem is air velocity? Got any leaks, even small ones? Are there any major differences between yours and mine? Did you use a rectangular inlet? I'm convinced that is a big plus. I think round inlets are prone to turbulance where the air streams merge and an upset like that can easily contribute to by-pass.
I think a round to rectangular transition could be fashioned from wood with no exotic angled cuts and you would get 90% of the benefit I am getting from my fab shop version.
Maybe u could some compression springs in the corners to carry some of the load of a full can and help in when the cam comes over center.
Quote from: dabullseye on September 25, 2011, 04:22:00 PM
Maybe u could some compression springs in the corners to carry some of the load of a full can and help in when the cam comes over center.
That could be a little tricky. I only have 1" of travel. Of that, 3/8" is to engage the drum groove and 1/8" is for overtravel. That means in the full retracted position, the top of the drum clears the bottom of the separator by just 1/2". If the compression springs kept the table from fully retracting, I might not be able to get the drum out. That's not likely to be a problem with a full drum, but if I need to get it out with a partial load, or no load at all, the springs could keep the platform raised.
However, your idea might be a good one for an entirely new design. I'm thinking four strong springs could provide the lift power, and the separator could then be suspended in a fixed position with no springs. To empty the drum there would have to be some kind of crank, or clamping mechanism, to compress the springs, and then release them to reseal the emptied drum.
AIR STRAIGHTENER - WHAT NOW?
In an earlier post I discussed the increased noise I am getting since I installed my separator. It is very annoying, so I began investigating the problem further and discovered that I mis-diagnosed the source. It is not the baffle or the plastic drum. When I put my hand around the neck of the separator exit pipe there was almost no vibration, but when I grabbed the neck of the DC inlet pipe, the vibration was very noticable. However, it is not a mechanical vibration, and it stops when the separator is disconnected. I became convinced that the vibration is from air turbulance resulting from my counter-rotation separator.
So, to test this theory, this evening I tried "plauale's" suggestion and stuffed my separator outlet pipe full of "straws" to straighten the air. Hope you're following this thread plauale! The results have really left me scratching my head.
First, here's a photo of the modification. I cut two light-walled plastic shipping tubes into 8" lengths. Then I stuffed as many as I could into the 5" separator outlet pipe and soaked all the contact lines with crazy glue. They aren't going anywhere unless they shatter, and then the fan impeller will eat them like rice crispies.
(https://www.dropbox.com/s/pcjvevlk2acsg7u/AirStraigthener.jpg?raw=1)
Here's what happened when I fired it up,
1) Big drop in noise level, 4-5 db. May not sound like much, but that's a huge difference in comfort level.
2) Amp readings dropped a little. That's not good, but I need to test this a little more.
3) Waste stream inside the separator now oscillates in a flat sign wave pattern, rather than continuously spiraling downward.
4) Waste stays suspended a little longer, but still separates.
5) A very small amount of by-pass occurs when hit with a heavy waste stream. I dumped more than 1/2 of a garbage bag of shavings in front of my floor sweep and then shoved it in. It would take three thickness planers to generate that much shaving dirt, but the separator still worked.
At this point I'm not sure what I want to do. I could do more testing - yuk! I could build a mirror image separator - double yuk! Or, I could leave it as is - maybe!
Update:
Here are two short video's showing the change in separator behavior with the air straightener added. The first video shows the amount of waste used in the test and the rate at which I was feeding it. The second video shows the change in the vortex. Compare this video to the one I posted in Reply#40 (no air straightener).
It would appear in the earlier video the waste stream is tilted down, while with the air straightener added it is tilted up. In hindsight, I should have looked at the waste stream from the opposite side. It is quite possible the waste stream always flows in a tilted plane, and all the air straightener did was rotate where that low point occurs. Can anyone verify this? I'd do it myself, but at this point removing the air straightner is quite a bit of work.
The video below with the air straightener makes you think the separator can't possible be working, but within a second or two of stopping the waste feed, the separator chamber is empty and the plastic bag shows only a few straggler chips have by-passed the separation.
So for the time being, I am leaving the air straightener in place. I can see no real loss of performance, and it is sooo... much quieter. The low frequency rumble from turbulence is gone.
https://www.dropbox.com/s/xngk0vs33gctl0g/AirStraightener01.MPG?dl=0 (https://www.dropbox.com/s/xngk0vs33gctl0g/AirStraightener01.MPG?dl=0)
https://www.dropbox.com/s/l7t2ntiqd2jg79f/AirStraightener02.MPG?dl=0 (https://www.dropbox.com/s/l7t2ntiqd2jg79f/AirStraightener02.MPG?dl=0)
UPDATES:
Added final photos of the lift table assembly to Post #85, and added videos of the separator performance with the air straightener installed. Those videos are in Post #92 above.
Very nice work. I want to see it suck on some MDF though so I can compare it to how mine works.
Quote from: Don_Z on September 27, 2011, 10:07:40 AM
Very nice work. I want to see it suck on some MDF though so I can compare it to how mine works.
Ship a box full to me. I'm trying to avoid making any MDF fines!
By the way, I thought you were working on a kitchen project. How do you have so much time for these separator fun and games?
Because I hate watching lacquer dry...
I am following Retired2, and I think that tubing you used is more appropriate than straws. However this IS quite a head scratcher, the only question i had after watching the videos was the bell-mouth outlet seemed to be a bit deeper in the separator on the later video. Don't know if it makes much of a difference, I assume you played around with that since you have little markings on the side... And then again, as you say, there is little loss in performance and lower noise: so you could just call it a success. Plus the whole setup looks really nice!
Quote from: plauale on October 07, 2011, 01:14:12 AM
However this IS quite a head scratcher, the only question i had after watching the videos was the bell-mouth outlet seemed to be a bit deeper in the separator on the later video.
You're really observant, plauale - I didn't think anyone would spot that difference. After I shot the second video, I discovered the outlet pipe had slipped down without my knowledge. I think it slipped down when I pushed the "straw" bundle in place. I've since pulled it back up and reapplied fresh rope caulk. A quick check didn't reveal much difference in the performance of the waste stream. However, I didn't spend much time looking. I'm waiting for the anemometer I ordered to arrive, then I hope to be able to provide more definitive answers.
Well, I received my new anemometer on Friday, so today I spent a really long day doing more testing. It was a long day because I had to start by removing my separator suspension system so that I could make all the setup changes I wanted to measure. It didn?t help that I have one helluva cold, or whatever it is.
For those of you that like a lot of numbers you will have to wait until tomorrow. I need some time to format the data. I have anemometer, ammeter, and sound meter readings for a variety of setups.
For those of you who don?t like numbers, here is a brief summary of the findings:
1) The bellmouth outlet works better than a straight pipe (Straight pipe w/air straightener matches or exceeds bellmouth w/o air straightener).
2) No performance penalty for the air straightener. It actually improves the performance of both the bellmouth and the straight pipe.
3) The depth of the straight outlet pipe makes no difference in velocity readings.
4) The depth of the bellmouth outlet pipe shows very slightly higher air speeds when it is set high than when it is set low.
5) Noise levels are lower with the air straightener installed (less turbulence).
6) Meter readings are more stable with air straightener installed (less turbulence).
7) ?Plauale? is definitely not crazy! He's the one that suggested I install straws in my outlet pipe.
It is safe to say from the above summary and the data that follows, every close-coupled (to DC) separator should have an air straightener installed in the outlet pipe - regardless of separator rotation.
The $64K question is how would these test results change if my separator were not counter-flow? We?ll never know for sure because I don?t intend to build another one and go through all these tests again! But if I had to guess, I would say a same-direction separator would be better for those setups that do not include an air straightener. With the straightener, I would expect them to be the same.
Here?s some photos of my test setup. The first photo shows the quick and dirty mod I made to my floor sweep. This is the inlet pipe that was used for all anemometer readings. The second and third photo give you some idea of the distance to the DC.
(https://www.dropbox.com/s/1i8858knmjuv3tu/Testsetup-03.jpg?raw=1)
(https://www.dropbox.com/s/xv4xwv3wy7rhe3h/Testsetup-01.jpg?raw=1)
(https://www.dropbox.com/s/yiwzray05h4i9dw/Testsetup-02.jpg?raw=1)
NEW TEST DATA
O.K. Here's the test data I promised. The test with the filter bag removed was performed to get some idea how a Wynn Filter might improve test results. It's not a perfect test, but it provides a good approximation. (See additional comments below test data)(https://www.dropbox.com/s/u61g8xj47hfqh7i/TestData.jpg?raw=1)
I think it is worth making a few comments on the data above.
1) FPM data is an average of two readings, one at the edge of the pipe and the other in the middle of the pipe.
2) CFM are calculated numbers. They are not measured, and they are calculated on the basis of a 5" pipe which is what my system is.
3) Don't put too much faith in the absolute numbers - they fluctuate far too much. It is the relative differences that should be noted.
4) It is impossible to get a single test number that is 100% accurate and repeatable. Testing a DC system is not like checking the air in your tires where conditions are static and a good gauge will give you the same reading every time. With dynamic conditions like these tests, the numbers will be different everytime, but the relative relationships should remain pretty much the same.
5) Aside from the fluctuations that result from turbulance throughout the system, I've learned that at least two other things affect the numbers. The first is the temperature of the DC motor. A cold motor produces better numbers than one that has been running tests for an hour or more. I've also discovered that my Long Ranger relay adversely affects the performance. The penalty is extremely small, and would probably never show up in actual performance, but it can be seen very consistently with the test instruments. I'm not sure why this is happening because I checked the voltage, and the relay is passing full line voltage. Any electricians want to comment on this?
6) Air straighteners improve the performance of both the straight and bellmouth pipe by about 40-50 CFM - not huge, but not bad since it also improves noise levels as well. If I weren't burnt out, I would run a few tests on air straighteners. First, what shape works best? Would four longitudinal vanes produce the same results as a bunch of plastic tubes? How long(or short) should the straightener be? Where should it be positioned? My testing was done with the straightener placed nearly flush with the entrance to the exit pipe. Maybe it would be better if it were closer to the DC than the separator? Anyone want to take on these tests? I'm done.
7) You can see from this data that under the best conditions my separator imposes a performance penalty of about 300 CFM or 2000 FPM. That is substantial, and it is the difference between maintaining or not, the minimum recommended speed for conveying woodworking waste. I see no evidence that waste is settling out in my headers, but I can see small amounts of waste on machine beds that weren't there before. The other machines I would like to add to my DC system, such as a miter saw and radial arm saw, will need lots of air to be effective. When that time comes, I will probably be faced with a really tough decision.
If I make any any further changes to this post, other than the missing data in the table, I will highlight them in color.
Update:
Well, the test data with the filter bag removed was very disappointing. As you can see from the numbers, there is really no difference whether the bag is removed or not. I can think of two reasons for this. First, I turned my filter bag inside out and vacummed it before I started testing. So, it is essentially a "green" bag. Second, the CFM's in all these tests are not terribly high, so the filter bag is not being inflated very firmly.
As my filter bag develops more cake, I would expect to see test results that make a Wynn Filter look more attractive, but for right now I don't see any reason to rush out and buy one.
Well, are your eyes glazed over yet? If not, I want to share another discovery I've just made while checking my test data for consistency.
If all things are equal (and that is the key), ampere readings move in sync with the volume of air being moved, i.e. if ampere readings go up, more air is being moved, and if they go down, less air is being moved. So, when I noticed a comparison number in my data that was contrary to this simple rule, I dismissed it as an aberation resulting from the fluctuating readings produced by a DC system.
What I've since discovered is that it isn't an aberation at all, but rather it is part of a consistent pattern that shows the addition of an air straightener allows the fan to move more air with fewer amperes. If you go back to my test data and compare the numbers for a given test without the air straightener to the same test with the air straightener, you will see that in every case the fan is moving more air with fewer amps when the air straightener is installed. So, if your DC is marginally powered for your system, as mine is, milking every last ounce of performance out of the fan is important.
Sometime earlier I posted this paragraph from a Cincinnati Fan Engineering manual regarding duct inlet spin. The above discussion and test data seems to validate Cincinnati's statements. Again, you should keep in mind, all my testing was done with the separator close-coupled to the DC. So, I don't know how relevant any of this is when there is several feet of pipe, hose, or elbows between the two.
Duct Inlet Spin
"A major cause of reduced fan performance is an inlet duct connection that produces a spin or pre-rotation of the air entering the fan inlet. Inlet spin in the same direction of the fan wheel will reduce air volume and pressure ratings. Inlet spin in the opposite direction of the fan rotation will substantially increase the motor horsepower requirements. An ideal inlet condition is one which allows the air to enter the fan axially and evenly without spin in either direction."
Hey Don_Z, you've been awfully quiet recently, have you od'd on laquer thinner? :)
You need to get that kitchen project finished so you can get back to more important things like helping out with this separator testing!
On a more serious note, I was wondering if you have done any testing to determine whether the depth of the outlet pipe improves separation with MDF fines?
I don't have any MDF waste to test right now, so all I have to go on is my test data which shows a slight improvement in air flow when the outlet is deeper in the chamber, i.e. closer to the baffle. But with the pine planer shavings I have been using for testing I really can't see much, if any, difference in separation at the various positions.
Hey, all you lurkers, what's your experience? This thread has over 2600 views, surely some one out there has something worth sharing. Help out here - post something!
Actually, I have noticed that since attaching the bellmouth and dropping it down that I have zero bypass with mdf or any unlucky small kittens that happen to get sucked through. I have been reading your test results and have been waiting and considering if and how adding "air straighteners" would be adding to my system. I will say that I am considering buying a new 3 hp penn state or grizzly to replace the HF model I started this project out with. Need to get the uppers hung before the wife will let me do much of anything though :(
Quote from: Don_Z on October 17, 2011, 11:50:14 AM
I will say that I am considering buying a new 3 hp penn state or grizzly to replace the HF model I started this project out with. Need to get the uppers hung before the wife will let me do much of anything though :(
I suppose we could have quite an active thread on just Dust Collectors, but if money were no object, and of couse it always is, the one I would buy is the Oneida Smart Collector. It's a portable cyclone that somehow adjusts the sp to compensate for hose and port sizes. I think it can develop a max. of 20" sp. That's not exactly a shop vac, but it is considerably more sp than any DC I know of. And of couse, it is capable of moving plenty of CFM when it is needed, and it's quiet.
But that would take away the fun of building the separator then. Nice machine specs, but looks like a dated piece of crap. You would think for that price they would update the looks. I like the looks of the new Laguna models, but they perform terribly.
Quote from: retired2 on October 14, 2011, 06:23:07 PM
Sometime earlier I posted this paragraph from a Cincinnati Fan Engineering manual regarding duct inlet spin.
Duct Inlet Spin
"A major cause of reduced fan performance is an inlet duct connection that produces a spin or pre-rotation of the air entering the fan inlet. Inlet spin in the same direction of the fan wheel will reduce air volume and pressure ratings. Inlet spin in the opposite direction of the fan rotation will substantially increase the motor horsepower requirements. An ideal inlet condition is one which allows the air to enter the fan axially and evenly without spin in either direction."
Interesting to see that air rotation in any direction is detrimental to performance.
Also interesting to note entrance design losses (attached).
Appreciate all the effort you've put into testing and reporting back your findings.
just wondering if it would be better to put the straws rt on the DC since mine is mounted up on a platform and offset from the trash can
Quote from: dabullseye on October 22, 2011, 08:35:04 AM
just wondering if it would be better to put the straws rt on the DC since mine is mounted up on a platform and offset from the trash can
I doubt that it would make much, if any, difference. It should be beneficial either place. My straws are 8" long, and that was totally arbitrary, so I have no idea how long is long enough, or how short is too short.
Regards,
Retired2
p.s. My tubes were 1-1/2" diameter shipping tubes for some Krell aluminium tracks I purchased. I thought it would be easy to buy more, but I'm starting to think sourcing this thin wall PETG tubing is going to be a major problem. I can't find any suppliers unless I want to purchase a huge quantity. The only tubing I can find is heavy walled stuff, and you don't want to use that because you will loose too much area and probably generate some turbulance which is exactly what you are trying to eliminate.
check out fluorescent bulb safety cover tubes
Quote from: dabullseye on October 23, 2011, 04:24:12 AM
check out fluorescent bulb safety cover tubes
Where? Did a quick check of Amazon, Home Depot, Lowes, and Ace Hardware. No luck.
Quote from: retired2 on October 23, 2011, 06:45:59 AM
Quote from: dabullseye on October 23, 2011, 04:24:12 AM
check out fluorescent bulb safety cover tubes
Where? Did a quick check of Amazon, Home Depot, Lowes, and Ace Hardware. No luck.
I've seen them at Lowes and HD. They're 4 or 8' long and T-12 tubes are 1-1/4", so these might be just the ticket. You might not find them online, you might have to travel to a store.
Quote from: phil (admin) on October 23, 2011, 07:35:28 AM
Quote from: retired2 on October 23, 2011, 06:45:59 AM
Quote from: dabullseye on October 23, 2011, 04:24:12 AM
check out fluorescent bulb safety cover tubes
Where? Did a quick check of Amazon, Home Depot, Lowes, and Ace Hardware. No luck.
I've seen them at Lowes and HD. They're 4 or 8' long and T-12 tubes are 1-1/4", so these might be just the ticket. You might not find them online, you might have to travel to a store.
Thanks Phil. Thus far, all my searching has been on-line, so I'll check out the local stores. I did find this on-line source, but they don't have 1-1/2" diameter. The reason I like the 1-1/2" is it works out nearly perfectly for stuffing a 5" pipe.
http://www.tapplastics.com/shop/product.php?pid=274&
I tried laying out other diameter tubes in a 5" circle using paper templates, but that doesn't work because in reality the tubes get squeezed just a little into a slight elliptical shape. If they are too big, they flatten, too small and they won't stay put, and it is hard to glue the contact lines. So, the only way to really know how a given size will work is buy enough to try it. In fact, I've been thinking that what might work best is a mix of more than one size.
was thinking about golf club tubes and they are 1 1/2" dia and pretty robust. Here's an example. http://www.golfsmith.com/product/30032085/ztech-golf-bag-tubes
Quote from: Rick T on October 23, 2011, 10:52:39 AM
was thinking about golf club tubes and they are 1 1/2" dia and pretty robust. Here's an example. http://www.golfsmith.com/product/30032085/ztech-golf-bag-tubes
Since I'm a golfer, I thought about those too. Just haven't had a chance to stop into our Golf Galaxy to check them out. They definately are a different material, not that that matters as long as the wall thickness isn't too heavy and as long as they respond to some adhesive, preferably crazy glue. That makes it very easy to glue the stack together.
When I glued mine up, all the tubes were in contact with one another because they were squeezed snugly into a 5" pipe. Then I just held the pipe so it was tilted slightly below horizontal. Then I put a couple drops of crazy glue on each contact line. The crazy glue would run all the way to the other end where eventually it evaporates and the tubes are welded together. It would be nice if that worked with the golf club tubes.
Golf is far to frustrating for me so it's nice to know there may be some good that can come from it. As far as gluing them together, wonder if you could use spray foam? Spray a quick shot into voids between if that's what you are thinking about. Do that at both ends since it doesn't matter what the tubes do in the mid-section. That foam is a pretty powerful adhesive.
Quote from: retired2 on October 23, 2011, 08:02:13 AM
In fact, I've been thinking that what might work best is a mix of more than one size.
I was just at Menards where they have two different sizes, one for T-8, and another for T-12. I didn't check the diameters, but will next time I'm there.
so according to the chart, my unflange pipe is restricting the airflow by about 90%? so just by adding a bellmouth, i can increase airflow quite a bit(hopefully 90%)? that would be awesome but seems hard to believe.
where can i get a decent bellmouth in 6"? ive only found penn states(psi), but the radius stops right at the top of where it should transition into the actual pipe. thanks in advance to all.
Quote from: Rick T on October 23, 2011, 02:46:15 PM
Golf is far to frustrating for me so it's nice to know there may be some good that can come from it. As far as gluing them together, wonder if you could use spray foam? Spray a quick shot into voids between if that's what you are thinking about. Do that at both ends since it doesn't matter what the tubes do in the mid-section. That foam is a pretty powerful adhesive.
I'm not familiar with this adhesive, but if it fills any air slots, even the small ones between the tubes, I wouldn't use it. You don't want to give up anymore of the free area than is lost by the tube wall thickness.
Quote from: DarthVader on October 23, 2011, 03:05:54 PM
so according to the chart, my unflange pipe is restricting the airflow by about 90%? so just by adding a bellmouth, i can increase airflow quite a bit(hopefully 90%)? that would be awesome but seems hard to believe.
where can i get a decent bellmouth in 6"? ive only found penn states(psi), but the radius stops right at the top of where it should transition into the actual pipe. thanks in advance to all.
No, no, no, you are not restricting airflow by 90% You are losing what is called velocity pressure. Velocity pressure is the amount of pressure required to get air moving to a given velocity. As you lose velocity pressure, some static pressure is added. That static pressure represents the loss. Now don't ask me how to quantify that because I don't have that level of understanding. I can only refer you to the two different sets of test data that I've posted in this thread, and you can see there clearly is a tangible benefit. Since my second set of data included anemometer readings you can see the benefit in FPM or CFM. I would also like to refer you to another thread that I started that explains things a little better. That thread is titled "Bell mouth outlet pipe?", and it was started on August 4th.
I don't think PSI's bell mouth is any different than mine. They are all very short. You need to attach a stub pipe to them. The thread I mentioned in the previous paragraph has photos and dimensions of my bell mouth before and after I attached the pipe.
i would really talk to somebody at penn state and have them give you the real size of the bellmouth, they list em as 6" but they are more like 5.5
Quote from: dabullseye on October 24, 2011, 10:09:49 AM
i would really talk to somebody at penn state and have them give you the real size of the bellmouth, they list em as 6" but they are more like 5.5
Just for comparison, my bell mouth came from a local spiral pipe manufacturer, and while it was a nominal 5" size, the actual size at the neck was 4-3/4". It must be industry standard for them to be slightly undersized so they will fit into a starter pipe.
If you think about it, you want the bell mouth to be the male end of the first joint, because that is the direction of flow. If my bell mouth had been a full 5" in diameter, I would have had to crimp the end of the snap lock and insert it into the bell mouth. That would not have been nearly as desirable, and might even have negated some of the benefit of the bell mouth.
Quote from: retired2 on September 09, 2011, 10:01:24 PM
Quote from: RonS on September 09, 2011, 08:17:44 PM
One of the observations I noted from my ampere test was that the readings were lower with the separator removed than with the bellmouth installed. I expected them to be higher. I don't have an explanation for that, but it makes an argument that air rotation is not an issue.
I am not a science expert, but i believe that your amp readings show that the motor is facing more resistance when the seperator is in place, hence a higher amp reading. When you remove it you allow it to "relax".
Does this make any sense to you?
PS: i know this is an old post but i am very interested.
Quote from: jpgrenon on February 17, 2013, 07:01:28 PM
Quote from: retired2 on September 09, 2011, 10:01:24 PM
One of the observations I noted from my ampere test was that the readings were lower with the separator removed than with the bellmouth installed. I expected them to be higher. I don't have an explanation for that, but it makes an argument that air rotation is not an issue.
I am not a science expert, but i believe that your amp readings show that the motor is facing more resistance when the seperator is in place, hence a higher amp reading. When you remove it you allow it to "relax".
Does this make any sense to you?
PS: i know this is an old post but i am very interested.
CFM's and amp's move in unison. As the blower moves more air, amps go up. As it moves less air, amps go down. So, you would expect any test condition with the separator removed to be giving higher amp readings because the system is moving more air.
My comment regarding the test data in question was specific to two test aberrations only. The first was when the system was dead-headed, i.e. no inlet ports were open. With the system dead-headed, I expected the readings to be the same with or without the separator. The second condition that seemed contrary to expectations, was the test at my bandsaw with the bell mouth installed versus no separator. In that case, the difference, while contrary to what was expected, was very small.
Now, one thing that might explain both these aberrations is that I discovered after lots of testing and after the referenced test data was posted and my comment made, that as the blower motor heats up amp readings start to drop a bit even for the same test conditions. So, I should have performed all these tests after the motor had been running for some time to rule out differences due to thermal conditions in the motor.
Bottom line is I don't think you should make very much of these two isolated cases because given the circumstances they probably do not reflect a contradiction of what should be expected.
One last reflection on my comments. At the time I thought these data excursions might suggest that air rotation does not affect performance. As I later learned, and my subsequent testing showed, air rotation resulting from a close-coupled separator does indeed affect fan performance. And that is consistent with what industry experts also say on that subject.
Hi Everyone, I have found a source of thin wall tube used as packaging. You will find it here:
http://www.cleartecpackaging.co.uk/clear-plastic-tubes.html
I think you may find that they have a presence in the U.S.A. as well. Unfortunately they say they are bulk suppliers and can only offer large quantitys. They do offer mini packs:
34.6mmID x 200mm long – box quantity = 75 tubes = £40 that is about US$ 61.00
This is rather a lot of money but may be worth it particularly if several people can club together.
Keep innovating.
i dont think it is worth going to that expence. in a lot of the articals referenced in the clockwise/counter clockwise thread , most of the testers used an x shaped straightener.
im planing on cutting 2 8" wide(8"pipe) strips of sheet metal leaving a few tabs to bolt it inside the pipe. i will cut half way up the midle of both strips so that they can slide inside each other.
Alan. That sounds like a good plan. Please let us know how you get on with it.
I have a sample of these tubes now and they are perfect for the job but I cannot afford to spend that much. I would only need 11 for a 5" pipe. If I thought people would buy some off me at cost I might go for it.
I have a quick and dirty Thien lash up for the moment and of course it works but I want to make a top hat and I estimate that will cost me £100 in materials as I want to be able to experiment a bit so will need to duplicate some parts.
How do these cross straighteners work? What do they look like? Regards.
Hi All, I have found this simple air straightener that requires very little pipe length to work:
http://www.vortab.com/pdfs/Principles%20of%20Operation.pdf
Keep spinning.
Quote from: BernardNaish on April 09, 2013, 07:28:22 AM
Hi All, I have found this simple air straightener that requires very little pipe length to work:
http://www.vortab.com/pdfs/Principles%20of%20Operation.pdf
Keep spinning.
One look at that website tells me my plastic tubes are very cost effective!
Your tubes were very cost effective Retired2 and I managed to get a couple as free samples. Now I just need 9 more and I do not think their sales office will fall for it. I made some straws today by removing both ends of baked bean cans and folding each to form two tubes of about the right diameter. It did not appear to make any difference to the DC performance. I think this is probably because my system is far too turbulent with three right angle bends in the eight feet of 5" diameter steel tubes between my Thien and the DC fan. Also the tins are only 4" long.
To solve this I am going to get rid of the trolley and build a wooden frame, as you did Retired2, so that I can mount the fan directly to the DCs' rudimentary separator. This will get rid of a 2 foot long rectangular section duct that has a slow 90 degree bend and increase its height enough to have just one right angle bend and two feet of pipe. I think I will also be able to have a 15" length of straight pipe leading directly into the fan inlet. However I will install the straws as and when I can get hold of more suitable plastic tubes. I need to practise sweet talking sales staff.
I had hoped not to get so involved in researching but I find I cannot shake off thinking about and tinkering with Thiens. To have any hope of being able to get back to making furniture I think I will just have to make my top hat and do the work ASAP.
retired 2,
I wanted to thank you for all the work you did on your project and the time you took to make measurements etc. I copied some of your excellent ideas and learned from your build. I added a bellmouth and air straightener based on your data. My build is larger than and although I have not fired it up yet, I am hoping it will work well.
When I have purchased Universal T-Track from Rockler and Aluminum Miter T-Bar from Peachtree, they have been shipped in plastic tubes. I kept the tubes because I thought that they might be useful for something. Now, I know what I can do with them.
Quote from: ORBlackFZ1 on March 13, 2014, 12:01:44 AM
When I have purchased Universal T-Track from Rockler and Aluminum Miter T-Bar from Peachtree, they have been shipped in plastic tubes. I kept the tubes because I thought that they might be useful for something. Now, I know what I can do with them.
That's exactly where mine came from, Rockler T-Track! However, I think it was Phil who first suggested the best source, i.e. protective sleeves for fluorescent tubes from one of the big box stores.
nope it was me who said to check out the light tubes
The fluorescent tube covers work well. I came up with a combination of T12 and T8 sizes to create a snug fit in 6" duct. They are easy to cut and punch holes in to be able to fasten them together.
Question regarding the tubes....
I designed my Top Hat rotation in the same direction as my DC impeller rotates. Do you think that I will need the tubes when I connect the Top Hat directly (with six (6) inches of flexible hose, of course) to the Top Hat?
Thanks,
Eric
definetly put the air straightener in . it will only help .
Quote from: ORBlackFZ1 on March 14, 2014, 01:52:03 AM
Question regarding the tubes....
I designed my Top Hat rotation in the same direction as my DC impeller rotates. Do you think that I will need the tubes when I connect the Top Hat directly (with six (6) inches of flexible hose, of course) to the Top Hat?
Thanks,
Eric
Do a search on air straightener. It's been covered multiple times, rotation in either direction is undesirable.
Alan & Retired2:
Thanks for the response.
I found the reading from the search of "air straightener" very interesting. It looks like I have found a use for those Rockler and PeachTree tubes.....
Eric
Retired2:
You're killing me. :P I'm about ready to create more sawdust and build a top hat.
How did you cut the dados in the retaining rings? I've cut many a dado but never into something that was round.
My first theory was that you cut them while the piece was square and then cut the circle, but I don't think so.
Help me out here before I go on a hunger strike. :-X
L
Quote from: Latham on May 09, 2014, 09:41:08 PM
Retired2:
You're killing me. :P I'm about ready to create more sawdust and build a top hat.
How did you cut the dados in the retaining rings? I've cut many a dado but never into something that was round.
My first theory was that you cut them while the piece was square and then cut the circle, but I don't think so.
Help me out here before I go on a hunger strike. :-X
L
As I recall I clamped a board across the rings and routed the dados, two at a time since they are 180 degrees apart. I probably used the waste rings to support the center.
Quote from: Latham on May 09, 2014, 09:41:08 PM
Retired2:
You're killing me. :P I'm about ready to create more sawdust and build a top hat.
How did you cut the dados in the retaining rings? I've cut many a dado but never into something that was round.
My first theory was that you cut them while the piece was square and then cut the circle, but I don't think so.
Help me out here before I go on a hunger strike. :-X
L
How about using a router attached to a circle jig? It worked for me when I created my Top Hat.
With the pieces cut to size (rectangle/square), drill a small hole in the center and put your circle jig centering pin in the hole. Route the dado with your router and a straight bit.
You can also use the router to cut the rectangle/square into a circle and then use it to cut the inside drop slot.
Eric
Quote from: ORBlackFZ1 on May 09, 2014, 11:34:54 PM
Quote from: Latham on May 09, 2014, 09:41:08 PM
Retired2:
You're killing me. :P I'm about ready to create more sawdust and build a top hat.
How did you cut the dados in the retaining rings? I've cut many a dado but never into something that was round.
My first theory was that you cut them while the piece was square and then cut the circle, but I don't think so.
Help me out here before I go on a hunger strike. :-X
L
How about using a router attached to a circle jig? It worked for me when I created my Top Hat.
With the pieces cut to size (rectangle/square), drill a small hole in the center and put your circle jig centering pin in the hole. Route the dado with your router and a straight bit.
You can also use the router to cut the rectangle/square into a circle and then use it to cut the inside drop slot.
Eric
I think he was questioning the dados that run radially to the rings.
R2:
Thanks for the quick response. That's a simple solution. I'll probably just crank out a long jig and use a pattern bit to cut those dados. Why I couldn't think of that may remain a mystery.
Now I can declare my hunger strike over and run into town and eat some busquits and gravy for a Saturday breakfast.
L
p.s. I cranked out a fiberglass/epoxy round to rectangular inlet pipe using the "lost foam" method this week. I'll start a thread on it on a day or two. Thinking about forming one out of sheet metal was making my head hurt. ;D
Quote from: Latham on May 10, 2014, 08:01:22 AM
R2:
Thanks for the quick response. That's a simple solution. I'll probably just crank out a long jig and use a pattern bit to cut those dados. Why I couldn't think of that may remain a mystery.
Now I can declare my hunger strike over and run into town and eat some busquits and gravy for a Saturday breakfast.
L
p.s. I cranked out a fiberglass/epoxy round to rectangular inlet pipe using the "lost foam" method this week. I'll start a thread on it on a day or two. Thinking about forming one out of sheet metal was making my head hurt. ;D
Good luck and keep us posted.
Quote from: retired2 on May 10, 2014, 12:31:16 AM
Quote from: ORBlackFZ1 on May 09, 2014, 11:34:54 PM
Quote from: Latham on May 09, 2014, 09:41:08 PM
Retired2:
You're killing me. :P I'm about ready to create more sawdust and build a top hat.
How did you cut the dados in the retaining rings? I've cut many a dado but never into something that was round.
My first theory was that you cut them while the piece was square and then cut the circle, but I don't think so.
Help me out here before I go on a hunger strike. :-X
L
How about using a router attached to a circle jig? It worked for me when I created my Top Hat.
With the pieces cut to size (rectangle/square), drill a small hole in the center and put your circle jig centering pin in the hole. Route the dado with your router and a straight bit.
You can also use the router to cut the rectangle/square into a circle and then use it to cut the inside drop slot.
Eric
I think he was questioning the dados that run radially to the rings.
Retired2:
Sorry, I missed that the question was about the dados for the vertical side supports. I thought he was asking about the dado for the top of the waste container....Oh well, part of getting old......
Anyways, I just cut vertical side support dados on the table saw with a dado blade. I used the square edges of the input side along the fence. I just had to be careful and make sure the square edge was along the fence.
This is one of the great things that I enjoy about woodworking, there are always multiple ways to get something done, depending on your tools and knowledge. Ask three (3) different woodworkers how to drill a hole and you could get three (3) different answers that all get a hole drilled.
Retired2:
You can read (and see) my first semi-serious build post here: http://www.jpthien.com/smf/index.php?topic=1117.0 It's about buliding my round to rectangular inlet out of fiberglass.
OrBlack:
"I just cut vertical side support dados on the table saw with a dado blade. I used the square edges of the input side along the fence. I just had to be careful and make sure the square edge was along the fence."
I take it you made these cuts prior to cutting the (square) pieces into circles?
And did you say somethig about being old? Yeah, age ain't easy sometimes but I like being an old-guy monkeying in my shop! 8)
L
Quote from: Latham on May 11, 2014, 08:41:58 AM
OrBlack:
"I just cut vertical side support dados on the table saw with a dado blade. I used the square edges of the input side along the fence. I just had to be careful and make sure the square edge was along the fence."
I take it you made these cuts prior to cutting the (square) pieces into circles?
And did you say somethig about being old? Yeah, age ain't easy sometimes but I like being an old-guy monkeying in my shop! 8)
L
Actually, I cut the vertical support dados after cutting the circles. My inlet sides were square enough to use against the fence. My input/output ports are six (6) inch diameter, so I had 10" on the one side and 14" on the other to run along the fence. Check out the photos attached.
This Top Hat separator is replacing an in-barrel Thien separator that had 4" input/output ports. The larger port size makes a huge difference with my Jet DC-1100. The volume flow is much larger than with the 4" ports.
A big benefit of being retired is spending time in the shop! A big drawback to being retired is not spending time communicating with humans. Just me and the wood .... and the wood usually doesn't talk back.... ;)
OrBlack: Thanks for the explanation and taking the time to upload the photos.
That's a serious looking separator.
L
Quote from: Latham on May 11, 2014, 06:22:00 PM
OrBlack: Thanks for the explanation and taking the time to upload the photos.
That's a serious looking separator.
L
Thanks. All the credit goes to Retired2, for his build postings and Phil, for this very wonderful forum. I just did the "grunt" work.
It is definitely a "serious separator"! It is a huge improvement over my previous 4" system. My 12" Jet Jointer and 20" Grizzly surface planer don't get clogged any more with the 6" ports on the Top Hat.
I am in the process of rebuilding my Jet DC-1100 to incorporate the Top Hat and barrel into one cart. This will reduce the dust collection foot print and improve the CFM. I will post a couple of photos in a new thread, when it gets completed.
I Love it! I'm just getting ready to start building, but like all of my projects I am creating a sketchup file for this. Once I am done I will share it as long as it is ok. All credit for design goes to Retired2. Amazing build!
Quote from: sk1pp3r on July 22, 2014, 08:54:34 PM
All credit for design goes to Retired2. Amazing build!
I'll take credit for the "amazing build" and some mod's, but the concept is Phil's. Without his work and ingenuity, I'd be like a lot of others on this forum, i.e. cleaning up dust and wood shavings with a 24" push broom and a snow shovel.
Fair enough. Credit to Phil as well although that's a given seeing it's his site and all the research he's done. ;D
Here is a start. Those silly curves are no joke in sketchup. ::) I have the 1/8th offset and will make a note to make the end of the curve on the left of the intake tighter, like Retired2 did, to decrease turbulence.
(http://i.imgur.com/zqCV4N7.jpg)
OK, Here it is. I'm still creating scenes to show the measurements in an easy way.
I included more support on the bottom underneath the baffle so you don't need a support rod. Someone on here earlier did that I think but can't remember their name.
Currently the bellmouth outlet pipe is 3.75 in from the top. Looks like 3" produces better numbers. I'll update that in the sketchup file.
I tried to create an irregular curve on the bellmouth, after reading the article Retired2 posted, but it's not very noticeable here. I did a 9" circle for the bellmouth, I'm not sure the actual diameter of the one Retired2 used. This looked about right. I have yet to add the air straightener but it will be an easy fix. Any final suggestions on what distance it should be from the opening of the bellmouth, or how far it should travel up the outfeed pipe?
(http://i.imgur.com/DiKqpnf.jpg)
From the bottom you can see the extra support. The left side under the baffle could be beveled to ease airflow but I was really having trouble trying to do this in the sketchup file.
(http://i.imgur.com/Tnudnwb.jpg)
Here is some detail from the inside looking at the inlet. You can see the Lexan that is recessed in the frame on top and the ends. It seems the consensus is Lexan and not acrylic. (I think I said that right).
(http://i.imgur.com/0hnjzEZ.jpg)
If anyone has any suggestions to add to the file before I finish it let me know. I'm going to add little dimension tabs in each scene so there is more clarity for others trying to build this design. Many Thanks again to Phil Thien, Retired2, Plauale, and any others I forgot!
Nice job sk1pp3r! I envy your sketchup knowledge, I wish I had the time to learn it, but the last thing I need in my life right now is one more piece of software.
Thanks! I envy your knowledge to do the testing, a lot of which I don't understand. I'm learning more and more every day but still have a long way to go with engineering. I somehow skipped physics in high school and college, while becoming a physician assistant, so I started on Khanacademy last week.
Nice work. The bellmouth should idealy have an eliptical shape. See:
http://www.jpthien.com/smf/index.php?topic=1098.msg5988#msg5988
There is something to be said to make this a 1 1/4 or 1 1/2 top hat. EG height of chamber is inlet height x 1 1/4 or 1 1/2. Its thought this may help separate fines.
Are the sketchup files available?
Good luck.
Quote from: BernardNaish on July 26, 2014, 12:42:44 PM
Nice work. The bellmouth should idealy have an eliptical shape
Thanks BernardNaish. That's exactly what I was trying to say when I typed "Irregular Curve". I just couldn't find the words at the time :-\
Quote from: BernardNaish on July 26, 2014, 12:42:44 PM
There is something to be said to make this a 1 1/4 or 1 1/2 top hat. EG height of chamber is inlet height x 1 1/4 or 1 1/2. Its thought this may help separate fines.
It is just as you describe. I wasn't aware of the suggestion you posted but was merely following the dimensions posted by Retired2. You guys know way more about this than I do. I'm just trying to post some directions on making the thing haha. A picture is below. My inlet is 4" and the outlet is a 5" circle to connect to my Harbor Freight DC.
(http://i.imgur.com/RsvJux8.jpg) (http://imgur.com/RsvJux8)
The Sketchup file was too large to attach here so I had to share the link below:
Retired2 Thien Dust Separator by Justin Hill (https://www.dropbox.com/s/xyix0d46ds7l0ov/Retired2%20Separator%20by%20Justin%20Hill.skp)
Sk1pp3r,
Here is a link to a table with dimensions for off-the-shelf bellmouth fittings. I'm sure Bernard is right that an elliptical corner is optimal, but I'm pretty sure the stock fittings will yield most of the benefits.
I missed the link
Quote from: sk1pp3r on July 26, 2014, 08:19:32 PM
I missed the link
Oops! Try this:
http://www.spiralmfg.com/hoodsf.htm
Quote from: sk1pp3r on July 26, 2014, 08:21:29 AM
OK, Here it is. I'm still creating scenes to show the measurements in an easy way.
If anyone has any suggestions to add to the file before I finish it let me know. I'm going to add little dimension tabs in each scene so there is more clarity for others trying to build this design. Many Thanks again to Phil Thien, Retired2, Plauale, and any others I forgot!
Thanks for posting the Sketchup drawings. They look very professionally done. My Sketchup drawing is not as well done as yours, but I would be happy to post it if it would help.
Here are a couple of details that I included on my 6" Top Hat build, that you might be interested in:
1. a lip, the thickness of the Lexan, right below it. This keeps the Lexan from slipping down and provides a nice shelf to set it on when assembling.
2. a notch, for the Lexan to slide into on both ends. This keeps the Lexan from slipping out of place and really makes assembly easy. The notches were chamfered at a 45 degree angle on the outside edge to minimize the air flow disturbance.
3. a strip of 1/16" X 3/4" red oak. This strip was glued to the bottom lip the lexan was sitting on. It overlapped the Lexan approximately 1/8". The top edge was chamfered at a 45 degree angle.
4. a notch in the top to hold the Lexan in.
Including notches for all sides of the Lexan, created a leak-free Top Hat for me. I did not have to apply any adhesive to seal any of the Top Hat.
It is always educational for me to see how others tackle a problem, so make sure that you post some photos during your build.
Thanks and have fun,
Eric
Quote from: ORBlackFZ1 on July 27, 2014, 11:51:52 AM
1. a lip, the thickness of the Lexan, right below it. This keeps the Lexan from slipping down and provides a nice shelf to set it on when assembling.
If you look at the sketchup file it does have a little lip. You may be able to see it in the inlet detail picture above. In my case though, the lexan is only 0.08, instead of 1/8in thick, so I had to change the diameter of the outer baffle circle to accommodate it. I also have the notch in the top for the lexan which you can see in the sketchup file. It is .25 inch deep. I like the idea you posted though about the chamfer and oak piece and may incorporate that.
Anything to make it leak free, thanks for the tips!
Thanks to all who participated in this thread. Especially sk1pp3r for the Sketchup model. Using rough dimensions from that model helped me design my own. I drew up mine in AutoDesk Inventor.
Once I get the drawings all finalized I will post a link to a PDF version of them.
I also need to find an economical (and local) source for 5" or 6" flex hose and light wall pvc sewer pipe. This separator isn't going to do much good unless I can connect it to my DC. And that has a 5" OD inlet.
OK, I finished the layout for my separator
(http://i188.photobucket.com/albums/z287/DominicGreco/SEPARATOR_zpsc147943d.jpg)
This will be hooked up to my Penn States 1HP DC1B. I have a very very simple, short run of (2) 4" dia PVC pipes that can be hooked to my bandsaw, tablesaw, lathe (when sanding), surface planer or jointer via a short run of flex hose. None of y tools are more than 12 to 15 feet away from the DC. This system works OK with my current rather inefficient trashcan separator. So I'm pretty sure the installation of this new separator will be an improvement.
My new Separator has a 5" air inlet since my DC has the same size. As I mentioned before, I need to find a source for 5" flex tubing or just use 6" (which I'd rather not do). If I can't find 5" PVC tubing, fittings, and flex hose, I may end up using 5" HVAC fittings. Not optimal, but better than nothing.
Like the model shown in this thread, the dust inlet for the separator is 3 7/8" x 5 7/8". I have a 4" round to rectangular transition shown in my model. Unless someone tells me that'll cause unending problems, that's what I planned on using.
I planned on buying a HVAC fitting and modifying it to fit, making my own transition, or finding someone to make it for me. I have AutoCad Inventor and their sheet metal package does a nice job of providing flat layouts on sheet metal components.
Any comments?
DominicG:
Thanks for posting the Sketchup drawing.
Regarding: "My new Separator has a 5" air inlet since my DC has the same size. As I mentioned before, I need to find a source for 5" flex tubing or just use 6" (which I'd rather not do). If I can't find 5" PVC tubing, fittings, and flex hose, I may end up using 5" HVAC fittings. Not optimal, but better than nothing."
Here is a thread that I started from another forum (http://www.woodworkingtalk.com/f32/pipe-diameter-vs-performance-59625/index2/ (http://www.woodworkingtalk.com/f32/pipe-diameter-vs-performance-59625/index2/)). Here is the text:
"Grizzly has good prices on their flexible hose. I am very pleased with the 5" and 6" diameter hoses that I received from Grizzly. They are very good quality. I would not order 5" and 6" diameter hose from Woodworker's Supply again. They are ok, but they are definitely less flexible than Grizzly's."
http://www.grizzly.com/products/5-x-10-Clear-Wire-Reinforced-Flexible-Hose/W1035 (http://www.grizzly.com/products/5-x-10-Clear-Wire-Reinforced-Flexible-Hose/W1035)
Here is another link for you: http://www.woodworkingtalk.com/f32/4-dust-collection-flex-hose-64176/ (http://www.woodworkingtalk.com/f32/4-dust-collection-flex-hose-64176/). Here is the text:
" Here are some of my favorite places to get anything related to dust collection (in alphabetical order):
1. Grizzly (http://www.grizzly.com/)
2. Harbor Freight Sales (http://www.harborfreight.com/)
3. Rockler (http://www.rockler.com/)
4. Woodcraft (http://www.woodcraft.com/)
5. Woodworkers Supply (http://woodworker.com/)
2 thru 5 have retail stores in my area (Portland, Oregon). All of them have web sites that you can purchase from.
Try using Google with the "dust collection flexible hose" search phrase."
ORBlackFZ1,
Thanks for the recommendations! I really appreciate them. That link to the 5" dia flex hose from Grizzly is just what I was looking for. :)
Once I start building my separator I will order that hose so it'll be here in time.
Here are some another sites that carry Woodworking dust collection supplies. I purchased all my 5" metal ducting and flex hose
from these companies. Fast delivery, good selection and price.
Winn Engineering:
http://wynnenv.com/products-page/woodworking_hose/
Kencraft
http://www.kencraftcompany.com/Dustindex.htm
Retired2,
I have been trying to read as many posts on this forum as I can, however, being new to both this forum and this technology, I am having a hard time finding a plan that I can use to build from. I am not trying to do anything out of the ordinary. I have a Harbor Freight 2hp dust collector and I want to put a separator on it. I have seen many verbal descriptions of how to build one, but I am a visual learner. Do you know of any posts or have any knowledge of a "set of plans" that may be avialable to build one of these separators that will either mount on top of a steel trash can or mount inside same?
Yes this site is certainly a long and involved read. Your best bet is to build a top hat along the lines of retired2's design. See here:
http://www.jpthien.com/smf/index.php?topic=563.msg3024#msg3024
It is quite long but gives all you need to know. Hope it goes well.
Quote from: RonS on October 05, 2014, 12:47:35 PM
Here are some another sites that carry Woodworking dust collection supplies. I purchased all my 5" metal ducting and flex hose from these companies. Fast delivery, good selection and price.
Winn Engineering:
http://wynnenv.com/products-page/woodworking_hose/
Kencraft
http://www.kencraftcompany.com/Dustindex.htm
Yup! I ordered my 5" and 6" flex hose from KenCraft yesterday. I also ordered a 5 x 5 x 5 Wye. They were a good bit more economical than Oneida or Grizzly
@mbeam
Same concept, different build method.... if you are a visual learner then you are going to be very happy when you click the link. You can use that info to build any design, like RetVet or your own.
Blow off the dust when you go its been buried for a few years.....
http://www.jpthien.com/smf/index.php?topic=429.msg2187#msg2187
-Jason
Question about Air Straightener:
Kudos to Phil, Retired2 and everyone else on this post. Fantastic!
Somewhere on this site I found a link for a paper that showed a cross section for a air straightener that had 6 or 8 vanes that each went from the side of the pipe to about half way toward the center point of the pipe--Saw it last night, but now I can't find it. Can anyone point me to it?
Thanks
Quote from: ctadds on December 16, 2014, 10:59:08 AM
Question about Air Straightener:
Kudos to Phil, Retired2 and everyone else on this post. Fantastic!
Somewhere on this site I found a link for a paper that showed a cross section for a air straightener that had 6 or 8 vanes that each went from the side of the pipe to about half way toward the center point of the pipe--Saw it last night, but now I can't find it. Can anyone point me to it?
Thanks
Sorry, I only have a vague recollection of a white paper on this subject, but I can't point you to it quickly. I guessing it was in the last 18 months.
After a quick search, I found this thread. Maybe it is what you are looking for:
http://www.jpthien.com/smf/index.php?topic=1048.msg5635#msg5635
Retired2, I'm looking for a different one, it showed a schematic for an air straightener that had 6 or 8 straight fins equally spaced that only each extended in about half of the radius leaving the center of the tube clear.
I'm contemplating shaping a bell out of pvc pipe and keeping it long enough to accomodate thin slots that would house the fins which would be secured to the exterior surface of the pipe in order to keep the interior as smooth as possible.
It seems to me that it would be a relatively easy and inexpensive build. Any thoughts?
Thanks, Craig.
Hello all, first post.
I've been lurking for awhile, and want to start a cyclone. I just ordered a HF 2hp dc. I plan on getting a Wynn filter after making a top hat. I like the top hat design because I think it looks cool to see the cyclonic action. And I seem to have landed here at "retired2's" version.
That said, my brain is about to explode with information overload!
I'm sure most if not all of my questions have been asked, but it's easier to ask again than search thru the mountain of info on this website.
ok, please bear with me,
1)I can somewhat understand the concept of the importance of widths, measurements and lengths inside the cyclone,, but why is it better for the bottom piece to be thin? Why not 1/2" and bevel the edge?
2) The conversation on Elliptical Bell Mouth Templates really makes me want to do something else, :-\
Has anyone made any kind of a list/cheat sheet with all the do's and don'ts involved in building a cyclone?
I understand how people can get obsessed with wanting to make the next one better,, but I just want to cut down on some dust I'm eating.
Thanks all.
Mike
You are in the right place. Build a top hat as described at the top of this thread. Most people seem to use the Brute trash can. Use polycarbon sheet instead of acrylic (Perspex). You can leave out the elliptical bell mouth to the exit pipe and add it later if you want.
I do not know why the thin baffle works best or if a bevel on the edge of thicker material will work. It is so easy to make it from 1/4" tempered hardboard that most just make it that way. It probably does not need much support but you might as well add it while you are at it.
Please ask if you have more question and cannot find them easily - though the search fuction usually brings up the asnswer. Let us know how you get on. Probably best to start a new thread if you do - as this one is getting too long.
Quote from: ctadds on December 16, 2014, 10:59:08 AM
Question about Air Straightener:
Kudos to Phil, Retired2 and everyone else on this post. Fantastic!
Somewhere on this site I found a link for a paper that showed a cross section for a air straightener that had 6 or 8 vanes that each went from the side of the pipe to about half way toward the center point of the pipe--Saw it last night, but now I can't find it. Can anyone point me to it?
Thanks
Is this what you wer looking for?
http://www.vortab.com/pdfs/Principles%20of%20Operation.pdf
Fred
So I am gathering all the materials I will need for the bellmouth Thien Top Hat. Just a couple things I am trying to get straight in my head:
1. I am thinking that 0.50" thick MDF would be effective while being a bit less material to deal with. MDF can be messy. I want to use it but at a thickness that while sufficient maybe does not involve cutting away so much material. Do we generally think 0.50" is sufficient as a thickness?
2 I know the rigidity of the hardboard for the baffle has been an issue that has been discussed. Would it make sense to go thicker than 0.25" as a means of improving the rigidity? I know people have mentioned that thinner is better for the baffle but maybe 0.25" is just too thin. That said, I guess regardless of the thickness of the hardboard baffle, offering it more support at the edge of the slot makes sense. What do we think about some dimension thicker than 0.25" for the hardboard baffle?
3. I am really struggling with where to find the makings of the inlet pipe. From the drawings it looks like we need something tapered and either round or rectangular at the top hat end to fit up to the opening in the top hat itself. Any help with that as I just cannot find anything fabricated that way other than a few reducers, none of them dimensionally adequate to the task. I guess going round at both ends of the inlet pipe is an option. It does not appear to be a good one though and you are still left trying to get something with a taper I think. So what are people using for an inlet pipe? I really don't want to get stuck fabricating one if possible as the junction between pipe and top hat is going to be critical.
4. finally, any support for incorporating a neutral vane at the inlet?
Completely understand if folks think the last question is off the wall. I am really just asking so that if it is something worth considering I can think about the material I would need for it.
Quote from: jnug on February 23, 2015, 10:10:02 PM
So I am gathering all the materials I will need for the bellmouth Thien Top Hat. Just a couple things I am trying to get straight in my head:
1. I am thinking that 0.50" thick MDF would be effective while being a bit less material to deal with. MDF can be messy. I want to use it but at a thickness that while sufficient maybe does not involve cutting away so much material. Do we generally think 0.50" is sufficient as a thickness?
2 I know the rigidity of the hardboard for the baffle has been an issue that has been discussed. Would it make sense to go thicker than 0.25" as a means of improving the rigidity? I know people have mentioned that thinner is better for the baffle but maybe 0.25" is just too thin. That said, I guess regardless of the thickness of the hardboard baffle, offering it more support at the edge of the slot makes sense. What do we think about some dimension thicker than 0.25" for the hardboard baffle?
3. I am really struggling with where to find the makings of the inlet pipe. From the drawings it looks like we need something tapered and either round or rectangular at the top hat end to fit up to the opening in the top hat itself. Any help with that as I just cannot find anything fabricated that way other than a few reducers, none of them dimensionally adequate to the task. I guess going round at both ends of the inlet pipe is an option. It does not appear to be a good one though and you are still left trying to get something with a taper I think. So what are people using for an inlet pipe? I really don't want to get stuck fabricating one if possible as the junction between pipe and top hat is going to be critical.
4. finally, any support for incorporating a neutral vane at the inlet?
Completely understand if folks think the last question is off the wall. I am really just asking so that if it is something worth considering I can think about the material I would need for it.
1) I think there have been several builds done with 1/2" plywood and 1/2" MDF, so it should be fine.
2) I would stay with the 1/4" baffle. What several people have done is to bring a support island out from the area under the baffle where there is no slot. But I would still make sure that support is set wll back from the drop slot, and especially at the end of the slot.
3) I have seen on this forum several "solutions" where commercial fittings have been pounded into shape, or wood transitions have been fabricated. None of them make an optimal transition, but all are probably better than simply cutting off a round entry pipe. I don't have a link to any of the solutions and unfortunately, it is a bit like finding a needle in a hay stack.
4) I'm not sure if a neutral vane would be beneficial or not. I have a long radius ell just before my transition, and I just figured the ell and transition piece are reshaping the air flow so much that a vane might just add more line loss.
I wondered if what I was seeing in some of the graphics was actually support for the 0.25" hardboard baffle. Even cut back away from the slot I suspect that should really help support it.
Sounds like I will just have to learn to be a metal pounder. Although, I have a couple friends with a body shop. No way I can get them to do anything for me this time of year in New England! The place is choked with winter crash business. But maybe in a month or so if I am having trouble I might be able to get them to pound something out for me.
You can bash your own from some pipe. See here:
http://www.jpthien.com/smf/index.php?board=1.0
Its very easy. Good luck and let us know how you get on.
I might see if I can get my auto body shop friends to put something together for me. The last of the great tin knockers are knocking metal in body shops around the country. I would like something that really fits as it just looks like an obvious leakage opportunity.
Either that or I might just give up any thoughts of shaping the end to anything other than simplest if it means I don't get a real good seal there. I am thinking all of the effort to shape that air passage is for naught if there is any leakage there or maybe just as bad given the location, added air turbulence.
Quote from: BernardNaish on February 24, 2015, 11:35:04 AM
You can bash your own from some pipe. See here:
http://www.jpthien.com/smf/index.php?board=1.0
Its very easy. Good luck and let us know how you get on.
Looks like a bad link Bernard, unless your intent was to just give him the entire Forum index.
I gotta' say that the inlet pipe that is in DominicG's graphic looks so much like some of the HVAC reducers I have seen at web sites that I am really wondering if that is what it is. But when I go and look at the dims for the HVAC reducers I see at HVAC parts sites, nothing actually looks like something that would work dimensionally.
I might have found something for inlet pipe options!
There is a company in Tx....Duct Direct that shows duct reducers both round to round and square to round as well as angled reducers. They just show the relative dimensions on the graphics at their web site. The person I talked to who really needed to forward me on said they do that because they actually make these in a number of different flavors. She did go on to say they sell to everybody.
So I have a call in to them and a name to talk to. I will find out what I can and post it up here. If you look at their Spiral Pipe and Fittings page you will see a number of things that might work depending on what sizes are actually available. Look at an F50 for example if you go there.
Anyway I will post up more as soon as I know more.
This below is not a working link but it should be the right URL for the Spiral Pipe and Fittings page.
http://www.ductdirect.com/products/spiral-pipe-fittings.php
Sorry about the bad link. I hope I have it right now:
http://www.jpthien.com/smf/index.php?topic=1157.msg6542#msg6542
I finally am getting back to my separator build. Too much work and to little time lately.
I have a question about the bellmouth. I did find your info again retired2. You are using a 5" bellmouth. Does that allow you to exit your separator with a 6" outlet and hose or are you using 5" throughout? I already have the 6" hose and hardware and had planned on 6" hose. Just wondering since I know we have to make a sleeve over the end of the bellmouth if the choice of 5" is determined to end up with a 6" outlet and hose?
I noticed that my link to the potential source for inlets does work. Those folks have yet to get back to me though. I see that "Spiral" has inlets and Bellmouths. Maybe I will just get both pieces from them.
I have most of the components..the mdf, the ply, the hardboard....need the lexan sheet to cut and wood to build the support for the lexan. I think I know you used maple retired2. Anything particular drive that decision?
Quote from: jnug on March 12, 2015, 04:28:04 AM
I finally am getting back to my separator build. Too much work and to little time lately.
I have a question about the bellmouth. I did find your info again retired2. You are using a 5" bellmouth. Does that allow you to exit your separator with a 6" outlet and hose or are you using 5" throughout? I already have the 6" hose and hardware and had planned on 6" hose. Just wondering since I know we have to make a sleeve over the end of the bellmouth if the choice of 5" is determined to end up with a 6" outlet and hose?
I noticed that my link to the potential source for inlets does work. Those folks have yet to get back to me though. I see that "Spiral" has inlets and Bellmouths. Maybe I will just get both pieces from them.
I have most of the components..the mdf, the ply, the hardboard....need the lexan sheet to cut and wood to build the support for the lexan. I think I know you used maple retired2. Anything particular drive that decision?
My system is 5" throughout, no 6" anywhere. My DC has a 5" connection. The only maple I used was where the transition piece is connected to the separator. I used maple simply because I had some scrap laying around and I wanted something with strength to mount the steel inlet pipe.
Well maybe i will ge some 5" hose and put the 6" I have in storage. If I remember it correctly folks have mused that 5" is actually optimal for this separator system. I could be wrong on that but I think that is how I remember it.
Thank you Phil & Retired 2.
I stole the bellmouth & air straightener idea & used part of a 6" Aeroport for the bellmouth. Precision port makes the kit.
This is an in can baffle now. When I have free time I'll build a top hat. Then I'm really gonna copy Retired2!
Quote from: JonWho? on March 14, 2015, 08:35:53 PM
Thank you Phil & Retired 2.
I stole the bellmouth & air straightener idea & used part of a 6" Aeroport for the bellmouth. Precision port makes the kit.
This is an in can baffle now. When I have free time I'll build a top hat. Then I'm really gonna copy Retired2!
Be careful with the 6" bellmouth. I'm seeing occasional reports of increased waste bypass attributed to the bellmouth. i don't think it is the bellmouth per se, I think the problem occurs when people put a 6" bellmouth in a separator with a diameter that is too small. The flare on a 6" bellmouth is large in diameter, and that puts the exhaust pick-up closer to the perimeter where the waste is swirling.
Thank you. That's logical.
This is made out of ABS so I flush trimmed the flange & popped off the vertical support to decrease the overall size by about 7/8".
I will keep a watch on it & maybe go slightly larger with the Top hat.
Guess we're gonna find out!
Funny how every time I have an idea, someone is there to say be careful.
And I haven't even asked anyone to hold my beer yet!
Do you remember the overall outer diameter of the bell mouth?
Thought I'd seen it on here so I'm likely overlooking it.
Quote from: JonWho? on March 30, 2015, 02:29:15 AM
Do you remember the overall outer diameter of the bell mouth?
Thought I'd seen it on here so I'm likely overlooking it.
http://www.spiralmfg.com/hoodsf.htm
i got mine thru penstate ind. its spun steel. i took my off within the first week because it didnt fit my pipes and i had to turn an adapter out of wood. since im no rocket scientist and dont have any real fancy equipment to test my setup except what i can see with my eyeballs i could see more bypass from my lathe sanding and my drum sander. and as i have said before in 3yrs i have less than a quart of fine dust in my bag on the bottom of the 50-850 ring. also my center outlet pipe does not extend into the chamber as far as what everybody else does.
od= 9.5" (9 1/2" )
id= 4.75" (4 3/4")
ht= 2.625" (2 5/8")
Thank you. My appologies if you've posted the link several times.
I was curious about the increased waste bypass associated with the 6" bellmouth that R2 mentioned earlier
The 6" bellmouth I'm using has a 1 3/16" radius & the overall diameter is smaller than R2's 5" bellmouth. The smaller radius will cause more turbulence than the 2" radius in the 5". It's still gonna be better than a straight pipe.
I could just make my own by stacking layers of scrap Type 1 Pvc & use my 1.5" Roundover for the flare. Then I can machine a Roundover on the outside & chamfer the back of the flare.
Of course if I go that route I might as well make one for each machine too. I sure know how to create a lot of work for myself! I don't believe there's an end to what can be tried & tested.
On a side note. Retired2, Crazy that bellmouth weighs 1.5 lbs!
JonWho,
If you do some searching on the internet you will find that a true bellmouth is the most efficent entry port, and a straight pipe is the worst. However, what you will also find is that many variations produce a good deal of the benefit of a bellmouth. Even a flat flange on the end of a straight pipe is more efficient than straight pipe.
Now all this efficiency stuff has to do with airflow, it has nothing to do with waste separation. And it now appears there is some evidence suggesting that a large bellmouth flange in a separation chamber that is not sufficiently large will suck in more fine waste than a straight pipe. So, given the variety of pipe endings that come close to the efficiency of a bellmouth, it is possible that the best solution is a trimmed down bellmouth flange, or even a fabricated radiused tail piece fitted onto the outlet pipe. In fact, the bellmouth you say you have, might be the ideal fitting!
Retired2 - I have been following yours and many others designs and am about to embark on some variation of the many shown but will start using my DC ring with a baffle. I wanted to start with some baseline measurements. You mentioned earlier in this tread that you measured the FPM at the center and edge of the pipe. Is there any reason for the two and is there anything special about how to measure the edge flow (besides bringing the edge of the meter to the edge of the pipe - on a 5" pipe that is only 1.5-2" move)
This forum is great - I am glad to see there other over analyzers like me on this site (-:
Thanks,
Carl
Well I have answered my own question. I started taking some baseline measurements of my Jet DC1100 (original) with various piping and different turn combinations. 4,5 and 6 inch duct and PVC (4") along with short and long radius turns. I will post data soon but preliminary test supports significant efficiency in larger pipes and turns. I know I can't support 6", but 5" shows a big improvement over 4" and larger turn 90s show better performance as well.
This has all been stated before but I did some preliminary theoretical calculations based on my small shop and runs and didn't think there would be much difference....there is!!!
The center/edge FPM measurement was interesting as the flow is reduced on the edge (as you would expect) more than I thought.
I will post my data and my build progress in another thread in the week or so.
Carl
Quote from: Carl on April 05, 2015, 11:39:48 AM
The center/edge FPM measurement was interesting as the flow is reduced on the edge (as you would expect) more than I thought.
Carl
I've often wondered if I could use that to make an in-pipe separator. I've watched my clear plastic pipe while dust is flowing and I can see the dust hugging those walls.
phil how much does static play in that dust hugging the sides of tube
Quote from: retired2 on March 31, 2015, 02:27:28 PM
JonWho,
If you do some searching on the internet you will find that a true bellmouth is the most efficent entry port, and a straight pipe is the worst. However, what you will also find is that many variations produce a good deal of the benefit of a bellmouth. Even a flat flange on the end of a straight pipe is more efficient than straight pipe.
Now all this efficiency stuff has to do with airflow, it has nothing to do with waste separation. And it now appears there is some evidence suggesting that a large bellmouth flange in a separation chamber that is not sufficiently large will suck in more fine waste than a straight pipe. So, given the variety of pipe endings that come close to the efficiency of a bellmouth, it is possible that the best solution is a trimmed down bellmouth flange, or even a fabricated radiused tail piece fitted onto the outlet pipe. In fact, the bellmouth you say you have, might be the ideal fitting!
R2, Thank you for the response. We're on the same page. I'm no engineer but I know a little about bellmouths. Maybe very little but it's something. Lol.
In short, We use them in my line of work to reduce turbulence at the vent in vented speaker enclosures. That turbulence can be audible which is obviously undesirable for audiophiles.
I didn't proof read my post. If it seemed as if I was talking seperation with bellmouths I should have clarified. In the applications that we use them, the radius of the flare is smaller than what you're using. A 1" radius is usually all that's required to eliminate port noise. Because air flow moves both ways in a vent, the diameter of the vent will determine velocity. A smaller vent can cause port noise caused by the higher velocity even after the flared port eliminated audible turbulence in the end of the vent..
I'll try to whip up an example of what was in my head. I'm a visual person. I can't explain anything without props. Lol.
Now I'm rambling. Thank you again.
Edit: I guess I never mentioned understanding the increased efficiency.... Bare with me. :)
Quote from: dabullseye on April 06, 2015, 05:08:30 PM
phil how much does static play in that dust hugging the sides of tube
Not much I don't think. It is just a matter of the air moving faster through the center so the debris hugs the walls.
Great discussions! That top hat style is neat.
I primarily have been cutting balsa and basswood and ply and this has been great. I am now going to be cutting a lot of carbon fiber and G-10 and have a 3 year old that likes to hang out with me in the garage. So, I built a negative pressure room--mini clean room for my CNC to keep the dust contained. I have been reading up a lot and I want to be sure I am containing the very fine dust the Thien separator can not spin out. I have an old Delta 50-179 that I am going to use for the dust "room" and I would like to retrofit the dust bag to a canister. Is this just silly or a waste of time? I need a new Bag filter for the old Delta and I figured I would attempt to change that out to a canister type somehow. I will keep looking around on this site but I am having a hard time finding just a canister filter setup I can just plumb my existing exhaust into. Any help to point me in the right direction? I figured I would replace the bag with a Wynn filter of some sort but not sure how to patch just the filter onto the exhaust port instead of the bag.
I would post a picture..but do not know how ???
Thanks!
-Eric
Has anyone considered making a bellmouth out of PVC. It looks like it has been done for the ports on sub-woofer speaker cabinets for some time now:
(http://www.subwoofer-builder.com/port-flares/Flare36mm.jpg)
Here is a link to someone doing it and he has a how to on how its done:
http://www.subwoofer-builder.com/flares-25mm.htm
I am currently working on a mold to try it myself. I will post info on how that works out.
I believe a bellmouth made this way can produce better results in a Thien tophat separator than a commercial bellmouth. Keep the flared flange smaller than a commercial unit and you will reap nearly all the benefits of improved air flow without the increase in waste by-pass.
Commercial bellmouths have a pretty large flange diameter, and when inserted in a typical separator with a diameter around 20" I believe they can increase the amount of wasre bypass. However, from my experience the amount is small and I still strongly advocate their use.
Finally got the mold made and the press completed. I have a fan with an 8" inlet I built for a Pentz style DC about 15 yrs ago. Therefore, I'm basing my top hat on the 8" inlet also. That made for a very large mold and press for the PVC. I plan to put the end of the PVC in a large pot of boiling water to soften it then press it onto the mold. If all goes well I will be attempting this tonight. The mold is made of multiple layers of MDF. I really could have used this DC up and running while turning all of that MDF on the lathe. After turning I covered it in glue and sanded it some more when that was dry. I figured I needed something to harden the MDF. The 8" PVC pipe has a wall thickness over 1/4" and im guessing it will take a lot to stretch it into shape. Wish me luck!
(http://i1308.photobucket.com/albums/s617/lance6651/IMAG0264_zpsrwdnu1pe.jpg) (http://s1308.photobucket.com/user/lance6651/media/IMAG0264_zpsrwdnu1pe.jpg.html)(http://i1308.photobucket.com/albums/s617/lance6651/IMAG0263_zps0xud1joz.jpg) (http://s1308.photobucket.com/user/lance6651/media/IMAG0263_zps0xud1joz.jpg.html)
(http://i1308.photobucket.com/albums/s617/lance6651/IMAG0267-2_zpsti5zetee.jpg) (http://s1308.photobucket.com/user/lance6651/media/IMAG0267-2_zpsti5zetee.jpg.html)
Okay good luck Lance, I hope it goes easier than expected, and I can't wait to see the results.
I can't quite tell from the picture, are you using a solid material PVC pipe or the cellular core type? I was going to make a wooden bell-shaped form on my lathe and push the pipe onto it using the tailstock while applying heat with a heat gun while slowly rotating. When I went looking for pipe yesterday, all I could find was cellular core schedule 40. I wanted the thinner DWV schedule 20 that looks like a more solid material. I don't know if it really matters but, the solid material seemed more promising.
Quote from: NCTinkerer on December 22, 2015, 10:20:20 AM
I can't quite tell from the picture, are you using a solid material PVC pipe or the cellular core type? I was going to make a wooden bell-shaped form on my lathe and push the pipe onto it using the tailstock while applying heat with a heat gun while slowly rotating. When I went looking for pipe yesterday, all I could find was cellular core schedule 40. I wanted the thinner DWV schedule 20 that looks like a more solid material. I don't know if it really matters but, the solid material seemed more promising.
I used a solid core Sched 40. At the 8" size I am using the stuff weighs a ton. I had limited success. I will get some pics and explanation up soon.
Here is what happened.
I brought a pot of water to a boil and then I placed the PVC in the pot for about 10 min checking every so often for flexibility of the PVC. (FYI... the heat only transfers a small way up the PVC so the only part that becomes flexible is the portion directly in the water. After it was flexible I placed it on my press but I could not get it to flair much at all. I placed it back into the water to heat it back up. after leaving it in for longer periods of time and multiple attempts I decided the water was just not hot enough. the second pic is the best flare I could accomplish:
(http://i1308.photobucket.com/albums/s617/lance6651/IMAG0270_zpsabwnva63.jpg)
(http://i1308.photobucket.com/albums/s617/lance6651/IMAG0272_zps5bvabhsd.jpg)
I then decided to try using vegie oil as it should attain a higher temp. I seemed to be working until I realized the PVC was melting an burning on the bottom of the pot.......oops. Now I am going to owe my wife a new pot. thankfully it was a cheepy. :P
(http://i1308.photobucket.com/albums/s617/lance6651/IMAG0273_zpsowqysqmr.jpg)
I then grabbed another pipe I had waiting. This time we held it in the oil and kept it from touching the bottom. This worked. I put it on the mold and sure enough it was flaring nicely until it started bulging further up on the pipe.
(http://i1308.photobucket.com/albums/s617/lance6651/IMAG0274_zpsrnfiysri.jpg)
I ran out of time and had to call it quits for the time being. Here are some shots of what I was able to accomplish:
(http://i1308.photobucket.com/albums/s617/lance6651/IMAG0276_zpsyoi64a24.jpg)
(http://i1308.photobucket.com/albums/s617/lance6651/IMAG0278_zpspdvppx5a.jpg)
I am trying to decide if I am staying with that or if I want to attempt it again. If I do it again I will heat up a smaller portion of the pipe so hopefully it does not flex and bulge further up the pipe.
Excellent work Lance, this is going to be very helpful for others than may attempt the same some day.
Lance, It looks like the end of the pipe that first hits your form is cut square across with a pretty sharp edge. Could it be trying to dig into the form? I wonder if easing that edge might allow it to follow the form more easily.
QuoteLance, It looks like the end of the pipe that first hits your form is cut square across with a pretty sharp edge. Could it be trying to dig into the form? I wonder if easing that edge might allow it to follow the form more easily.
I thought about that also.... after the fact. I went back later and rounded those edges to help with airflow. that's when I thought "I should have done this before hand". The flip side was that using the veg oil to heat it worked well as lube.
Quote from: Lance on January 05, 2016, 09:53:40 AM
QuoteLance, It looks like the end of the pipe that first hits your form is cut square across with a pretty sharp edge. Could it be trying to dig into the form? I wonder if easing that edge might allow it to follow the form more easily.
I thought about that also.... after the fact. I went back later and rounded those edges to help with airflow. that's when I thought "I should have done this before hand". The flip side was that using the veg oil to heat it worked well as lube.
Lance,
The wall thickness of that pipe is pretty heavy. Did you consider tapering the wall thickness in the last few inches of pipe. You could use a lathe or a large sander.
Quote from: retired2 on August 29, 2011, 02:42:01 PM
<snip> There were two things I was trying to accomplish with my baffle design and both created construction problems. The first was to avoid having a ledge along the outside wall of the drop slot. Of course, that meant there couldn't be any dado to hold the bottom edge of the plexiglass. <snip>
Has having a ledge along the outside wall of the drop slot been shown to cause any problems? It would seem that having a dado for mounting acrylic or poly both top and bottom (and inletting the two ends of the plastic) may alleviate the need to have any screws penetrating the plastic. I'm slowly getting the stuff together to build my own tophat, and this is one of the aspects that is making my head hurt!
Got the HF dust collector, the Wynn filter is on order, as is the impeller from Rikon and the bellmouth from Spiral Mfg.
I'll be changing the inlet plate on the HF dust impeller housing to accept a 6" inlet. My plate will be made from 3/4" MDO, and I hope to use a 3/4" roundover on the 6" inlet hole to give me a mini-bellmouth at that point. In hindsight, I should have ordered two bellmouths, one for inside the tophat and one for the inlet to impeller housing. Ordering two at once would have made the shipping cost a lot more reasonable per unit. Maybe I'll get a second bellmouth someday, but more likely, once I get this thing working, I'll just leave well enough alone.
I have a 4"x10" to 6" Round End Register Box that I plan to use to transition from a ceiling drop from the 6" main trunk to the tophat. Not as elegant or smooth a transition as R2's, but compact for my application (very small workshop). Internal tophat hat height planned to be 10" to match the register box.
Regarding the bottom of the tophat, planning to layer it, top layer would be either 1/8" or 1/4" hardboard with the 1-1/8" drop slot. The next layer down would be another layer of the same thickness hardboard, but with a 2-1/4" drop slot. The bottom layer would be 3/4" MDO plywood with a 3-3/8" drop slot. All this layering is for the purpose of stiffening the baffle while maintaining a thin edge on the drop slot.
Would 6" flex hose work as a coupler for 6" duct pipe? If so, anyone know where I can get short lengths? I only need to make two joints, tophat to impeller assembly, and trunk drop to tophat inlet.
Regarding air straighteners in the outlet of the tophat to the inlet of the impeller housing, I'm thinking of a very simple 3 vane (think of a Mercedes emblem) assembly. Any info or thoughts on how long this would need to be to be effective?
Also, I believe it was somewhere in this thread someone mentioned polyester as an alternative to acrylic or polycarbonate, but I don't recall that comment being developed further. Thoughts on whether this is a viable alternative, pros and cons? Is it available as a clear product, cost comparison, etc?
Sorry for the random stream of consciousness in this post...
There's just so many details to look at! And I'm trying to look at all of them before I make my first cut.
I bought some PETG clear plastic from McMaster-Carr 5/64" 24"x48" sheet from Mcmaster-carr it's about $21. There's a Youtube user "Marius Hornberger" a 20 year old who makes a segmented bucket and tophat thien baffle. He used PETG and not only did it hold up to his collector's suction it also bends into tight corners.
5/64" is flexible, but I wish I bought the next smaller thickness. I'm not sure when/if I'll build one of my own, but I have the plastic if I do.
copy and paste (Building a Thien-baffle Separator for the (Small Dust Collector #3) into youtube's search and you can see how he built his.
You might be thinking of PETG sheet goods, as it is in the polyester family. It is available in thin roll, or sheet from from the same plastics suppliers where one might buy acrylic and polycarb from. Property-wise it is between acrylic and polycarb... more flexible and shatter-resistant than acrylic, but better scratch-resistance than polycarb. In my book, just about the ideal material for the outer "skin" on a see-thru top hat design. If it has any disadvantage, it is that you can't run to your local hardware store or big box to pick it up... but a google or yellow pages search for "Plastics suppliers - sheet goods", will get you a source.
JeffQ, what thickness would you recommend for the PETG?
I was wondering if rounding over the inside edge of the Thien Baffle's drop slot would help at all.
Quote from: NoBreyner on January 12, 2016, 06:16:32 PM
I was wondering if rounding over the inside edge of the Thien Baffle's drop slot would help at all.
I don't think rounding over the inside edge of the drop slot would result in any appreciable difference in performance. It might help if the baffle were thicker than recommended. However, most of the waste is forced to the outside wall of the separator by centrifugal force, so it is the ouside edge of the drop slot that is far more important. For that reason, I built my separator so there would not be a "ledge" along the outside wall and the baffle.
Quote from: kayak on January 12, 2016, 08:23:45 AM
JeffQ, what thickness would you recommend for the PETG?
I think when I built my top hat I used something like an .080 or .100 thickness of the PETG. I was lucky enough to get what was pretty much an off-cut from one of the local plastics suppliers here for a great price. Anything around this thickness will allow easy forming around the plywood and top and bottom of the top hat, while still providing plenty of strength and vertical rigidity.
Vivak is one of the brand names for PETG, much like Plexiglas is a brand name for acrylic.
Guys, I scrolled through all the pages and failed to discover the sketchup files. Are they available? Thanks.
Quote from: Daniel3105 on June 16, 2016, 11:36:13 AM
Guys, I scrolled through all the pages and failed to discover the sketchup files. Are they available? Thanks.
http://www.jpthien.com/smf/index.php?topic=563.msg6317#msg6317
retired2 Thank you for posting the sketchup file. That will be very useful to me. I am getting ready to build a new top-hat for my up and coming Gatton-CNC and I like some of the mods you have made. So far my top-hats have all had metal in place of the Plexiglas and small 5 gal. buckets. I like the idea of being able to see whats going on.
Mike
Hello,
I'm planning a separator for my 1-1/2HP dust extractor. Unfortunately mine is only equipped with a 4" outlet. So any CFM that I can avoid to lose with the separator is important. With its 11" turbine, it is rated at 700cfm and 40m/s
I plan to use the same design with rectangular inlet and bellmouth outlet + air straightener. That's why I did not create a new topic. If you think should create a new topic, feel free to let me know.
I also have concerns in footprint for the separator. The height is not such a problem (Probably I will extend it to a 2H design).
I found a those nice barrels that are only 15-3/4" dia with 12-1/2" opening. They are quite beefy with nice handles and locking lid. Note, that I don't plan to use the lid on the picture to make the top hat. It would be only used for transport when needed put it in the car to go to the waste collection center.
(http://www.leroymerlin.fr/multimedia/304141217/produits/fut-de-maceration-aerien-garantia-cylindrique-bleu-60-l.jpg)
The 20" garbage cans that I can find are not so robust or really expensive.
I undertood that the wider the separator, the less SP drop I will get. I also undertood that with 4" inlet and outlet there is a big risk of bypass. But what if my round to rectangular transition is quite long with tall but thin rectangular section (let say 5" x 2-1/2"). I would make the transition part 20" long.
As a comparison I see that the CV1800 cyclone from clearvuecyclones with its 6" inlet and outlet is 18" diameter but it has a long round to rectangular transition (quite thin but tall at the end rectangular section). Keeping those proportions would mean 12" diameter for 4" outlet and inlet. But maybe in this case, it would be safer to skip the bellmouth and just keep the air straightener.
Are there any things that I missed? Is the top hat so much different from the upper part of a cyclone? Or do you think it could work.
Benjamin.
Where did you get the bellmouth?
Quote from: kmerkle on June 08, 2017, 01:17:32 PM
Where did you get the bellmouth?
I'll second that request.
Quote from: Alan H on October 07, 2017, 07:39:41 PM
Quote from: kmerkle on June 08, 2017, 01:17:32 PM
Where did you get the bellmouth?
I'll second that request.
I got my bellmouth from a local spiral wound pipe fabricator. They also fabricated the custom dust hoods for my thickness planer, jointer, and the round-to-rectangular transition piece for my separator.
Bellmouths are available from a number of online sources, but off the top of my head I'm not certain which ones. Start with PSI (Penn State Industries) or Oneida Air.
I got a 6" bellmouth along with other fittings from here:
http://warehousecatalog.rlcraigco.com/viewitems/ductwork-take-off-fittings/spun-bellmouth-take-off
Prices were decent and they were pretty easy to work with. Selection is somewhat limited however and 6" is the smallest bellmouth they list.
I've been reading all the posts on here since I'm trying to find some answers to questions regarding building either a top hat or internal baffle. Of course I did this after starting an internal system. I think I'm going to forgo the space issue I have and go with the top hat build. I've noticed much discussion regarding the use of one form or another of plastic for the side of the unit. There appears to be issues with it cracking in some instances. Is there some reason galvanized steel can't be used? It obviously isn't going to crack, even with holes drilled in it.
thanks,
Joe
Quote from: OCJoeR on January 08, 2018, 01:23:24 PM
I've been reading all the posts on here since I'm trying to find some answers to questions regarding building either a top hat or internal baffle. Of course I did this after starting an internal system. I think I'm going to forgo the space issue I have and go with the top hat build. I've noticed much discussion regarding the use of one form or another of plastic for the side of the unit. There appears to be issues with it cracking in some instances. Is there some reason galvanized steel can't be used? It obviously isn't going to crack, even with holes drilled in it.
thanks,
Joe
The reason is you can't see through steel!😄 Is it critical? No, but when a plug develops, or you overfill your drum, it's nice to be able to see at a glance if your separator is jammed ir not. And when you clear the jam it is nice to know at a glance that you've got it all.
I glance at mine quite often, because the way mine us buttoned up it is one helluva mess to clean out. I've done it several times with wet shavings, so I'm paranoid.
The guys who have used Lexan don't seem to have the problems with cracking the way plexiglass users do. However, Lexan isn't nearly as cheap. And many places will not cut sheets to smaller sizes. Forget the big box stores, go to a place that sells only glass, shower doors, and mirrors. Mine shop will cut anything I want and he charges only for what I take, and very fair prices.
Hi Retired,
If I neglected to say it before, great thread! And great photos.
I knew it had to have something to do with watching saw dust and chips, lol. I guess I'll go with it. I'm wondering if heating it as the holes are drilled and while inserting the screws through it will help with the cracking issue. I'll cut a strip and give it a try and report back.
Joe
Quote from: OCJoeR on January 09, 2018, 08:44:31 AM
Hi Retired,
If I neglected to say it before, great thread! And great photos.
I knew it had to have something to do with watching saw dust and chips, lol. I guess I'll go with it. I'm wondering if heating it as the holes are drilled and while inserting the screws through it will help with the cracking issue. I'll cut a strip and give it a try and report back.
Joe
If you are using plexiglass, I don't think heating is going to help. It is worth noting that hearing does make it very easy to bend the plastic to to ID of the separator. My wife's hair dryer worked fine. The plexiglass does have a memory, so when you remove the heat it quickly stiffens and wants to open.
Somewhere, if you search, I posted a video with a concept for attaching and sealing the plexiglass without screws. I had already finished my build or I would have tried the concept. The video shows it has great promise. If I can find the link I'll repost.
Quote from: retired2 on January 09, 2018, 06:58:46 PM
Quote from: OCJoeR on January 09, 2018, 08:44:31 AM
Hi Retired,
If I neglected to say it before, great thread! And great photos.
I knew it had to have something to do with watching saw dust and chips, lol. I guess I'll go with it. I'm wondering if heating it as the holes are drilled and while inserting the screws through it will help with the cracking issue. I'll cut a strip and give it a try and report back.
Joe
If you are using plexiglass, I don't think heating is going to help. It is worth noting that hearing does make it very easy to bend the plastic to to ID of the separator. My wife's hair dryer worked fine. The plexiglass does have a memory, so when you remove the heat it quickly stiffens and wants to open.
Somewhere, if you search, I posted a video with a concept for attaching and sealing the plexiglass without screws. I had already finished my build or I would have tried the concept. The video shows it has great promise. If I can find the link I'll repost.
Here you go, a challenge for you:
http://www.jpthien.com/smf/index.php?topic=573.msg3105#msg3105
I've been meaning to do a comparison between a cloth filter bag and a Wynn 35A Nano cartridge filter for some time. I finally got around to it recently - the test data is posted in the table below. Some of the data is repeated from a much earlier post (#99) for your convenience. This will allow you to easily compare air flow between 1) no separator, 2) no filter, 3) a 1.0 micron cloth filter, and 4) a Wynn 0.5 micron nano filter. The bellmouth and air straightener were installed in all tests except where the separator was removed.
Air flow measurements were taken exactly as before, i.e. several readings were taken along the edge of the inlet pipe and several were taken at the center. All readings were then averaged to obtain the final number. CFM's were calculated from the FPM readings.
The cloth filter bag is not new, but before the test it was turned inside out and thoroughly vacuumed. The Wynn filter has never been used. I was surprised the air flow readings were so similar for the cloth filter and the nano filter. It would be interesting to see how they compared after some period of use. However, that test would be a lot of work because it would require exposing both filters to the same kind of waste for the same period of time in order for the test to be valid.
(https://www.dropbox.com/s/bzn1exrdqrcafyb/WynnFilter2.jpg?raw=1)
Huh! I never would have expected the values between the new Wynn filter, Seasoned bag and No filter/bag to be so close... or for that matter for the separator to cause so much of a hit in airflow.
Has anyone seen data for adjusting the height of the bottom of the Bellmouth input relative to the height of the inlet? (I'm assuming a now-standard (I think) 2H system)
In reply #99 of this thread, I provide data for three different positions of the outlet. There may be other comments buried elsewhere in this thread. However, my build is not a 2H separator, so I don't know what conclusions you can draw from my data. I think quite a few people have built 2H separators, but I'm not sure it is the standard, and there is no hard data to prove it is any better.
Yup. Just found your post. Where's the self-smack-head emoji?
I'm preparing for a long distance move and a new shop. Perhaps I'll buy an anemometer, and play with that idea.
Hi Retired2,
I apologize since the begin for rise again (I guess) the same question but....
where I can find some plans with dimensions? I was reading hundreds of posts but nothin.... :-[
maybe I'm not able to find them in....
thanks a lot!
ciao !
Quote from: Lapdi Woodworks on December 10, 2018, 05:11:17 AM
Hi Retired2,
I apologize since the begin for rise again (I guess) the same question but....
where I can find some plans with dimensions? I was reading hundreds of posts but nothin.... :-[
maybe I'm not able to find them in....
thanks a lot!
ciao !
See Reply #3 of this thread. Those are my dimensions and should serve as a guide. Beyond that everyone adjusts the number to suit their own needs. Often, it is the drum size that sets the diameter of the separator. Inlet and outlet size depend somewhat on what you have for a blower and what size piping it uses.
The Thien separator is pretty forgiving. By that I mean you can build it with many different dimensions, but as long as you stick to the basic configuration it will work very effectively.
Hi Retired,
ok, I'll try to do my best, even because I'm using a shop vacuum cleaner motor, directed installed on the top of the separator. I did some calculations, starting from the data of the motor ( 120 cfm, 94 inH2O, 1400, 1.6 hp) and those are the average values of the commercial workshop cleaners.
I hope it works,
please let me know any suggestions,
thanks a lot.
Quote from: Lapdi Woodworks on December 10, 2018, 10:30:08 AM
Hi Retired,
ok, I'll try to do my best, even because I'm using a shop vacuum cleaner motor, directed installed on the top of the separator. I did some calculations, starting from the data of the motor ( 120 cfm, 94 inH2O, 1400, 1.6 hp) and those are the average values of the commercial workshop cleaners.
I hope it works,
please let me know any suggestions,
thanks a lot.
I didn't realize you were planning on using a shop vac to power your system. I am not sure my build is a very good model for a shop vac system. Shop vacs have a lot of SP, but they don't move much air. I'm afraid I can't give you much help for a shop vac system. I have no experience with them because I've always felt they are the wrong tool for the job, and if you make it the heart of your dust collection system, you can expect some disappointments.
I suggest you start a new thread soliciting help for your design. You will need to provide as much information about what you would like to do and how you plan to use the system. Is the shop vac to be stationery, or will it be moved from tool to tool? What kind of equipment is producing the waste you would like to capture.
Doing lots of make ready for my HF upgrade when it arrives. I've read and watched so many posts and videos and seen several different designs -- many of which seem to have the baffle positioned in different locations relative to the intake port. I know there is a prescribed place to position the baffle such that the baffle work correctly, but I'm wondering if anyone has tried just doing a full disc that is 1 1/8 smaller in radius than the bottom piece -- basically a baffle that is a smaller full concentric disc that would be held in place by the threaded rods? Did it work? Any problems?
Quote from: rondako on March 17, 2019, 11:58:09 AM
Doing lots of make ready for my HF upgrade when it arrives. I've read and watched so many posts and videos and seen several different designs -- many of which seem to have the baffle positioned in different locations relative to the intake port. I know there is a prescribed place to position the baffle such that the baffle work correctly, but I'm wondering if anyone has tried just doing a full disc that is 1 1/8 smaller in radius than the bottom piece -- basically a baffle that is a smaller full concentric disc that would be held in place by the threaded rods? Did it work? Any problems?
I suggest you start a new thread with this question.
As I've just finished most of my collector and in testing stage, I'm very curious about you bell mouth and did you make it or make it from some common object ? I need a 6" bell mouth.
Quote from: tommitytomtom on May 01, 2019, 03:15:34 PM
As I've just finished most of my collector and in testing stage, I'm very curious about you bell mouth and did you make it or make it from some common object ? I need a 6" bell mouth.
Bought it locally from a spiral wound pipe shop. You should have no trouble finding one on the internet.
How did you make the Bell Mouth ?