J. Phil Thien's Projects

Why not?

I do a lot of stuff that isn't specifically related to dust collection or doweling jigs, so I thought I'd create a new board for general woodworking posts.

Feel free to post your projects, too.

I could use a SketchUp file matching what has been done in this thread:

http://www.jpthien.com/smf/index.php?topic=227.0

It would help me tremendously if you have that type of artwork.  If so, and you're willing to share, please let me know (reply to this thread is probably the most reliable).

BTW, if nobody has it but someone wants to create one, I'd PayPal $20 for the effort.

These are the pics from Ray Schafter (also known as rsquest) separator with side inlet.  Looking very nice so far, can't wait for further reports.

Received an E-Mail from Robert Wong today with his window he has added to his can.  Seeing as I'm guilting of overfilling my can recently, I thought I'd post this here.

Contributions can be sent via PayPal to:

     cgallery [at] yahoo [dot] com

Donations may also be sent via snail mail to:

     Phil Thien
     4606 N. Wilson Dr.
     Shorewood, WI 53211

Contributions are completely and totally voluntary.  I basically use them for materials for prototypes and equipment for testing.  I've probably received approx. $450 to date.  And every cent is greatly appreciated.

BTW, if you use snail mail, please be sure to include your online "handle."  A couple of times I've recieved an envelope with some cash and a first and last name that don't ring any bells.

You can also find a "Donate" link at the mothership (http://www.jpthien.com).

I get lots of E-Mail about my doweling jig.  I figured I'd start a discussion group where doweling jigs (especially shop-built ones) can be discussed.  I'll post the Rockler adaptation soon.

I know a lot of people have asked how well a baffle-equipped separator works compared to a real cyclone.  Some people have expressed surprise that some flour is able to get by the baffled separator.  I know I have read posts on various woodworking forums that leave the impression that a "true" cyclone "gets it all."

The photo below shows the bottom of a Dust Deputy bin and the bottom of the shop vac that powered it after a little use.  I'd guess there is less than a quart of dust in the Dust Deputy bin, and there is already a decent sized "swoosh" in the bottom of the shop vac.

I've also read reports from objective Oneida and ClearVue users that clearly indicate that they do, in fact, get a decent amount of flour to their filter stacks.  How much obviously depends on many factors, but nobody gets nuttin'.   ;D

My point isn't to claim my baffle design outperforms a true cyclone.

The point is to reset the expectations of those expecting any separator technology to get 100% of the entrained particles.

The photo accompanied a review of the DD in Power Woodworking magazine, March 2008 issue.

QuotePhil,

I planed some wood this morning.  I filled the 30 gallon can up to the baffle with only about 1 cup of carryover to the DC (I stopped as soon as I saw the carryover).  In fact, there was an indent of the baffle in the top of the chips in the can, with a 240 degree pile about 1 inch deeper (coming above the lip of the baffle) when I removed the lid.  Pretty spectacular design!

Thanks!
Matt

QuoteHey Phil I just got mine working as I just got my DC.  I ran an add in Woodnet that I was looking for one and a nice guy in Florida hooked me up with a Penn State 1-1/2 HP portable unit and it works great.  I sanded and planed for about 4 hrs. yesterday and filled the 20 lb can with chips and dust and the bag didn't even have a handful of stuff in it!  I'm going to get a high quality felt 1 micron bag and see what happens next.  As you can see in the photos I mounted mine right on top of the separator lid.  I wanted the shortest and most direct connection for the inlet into the DC.  Also, as you can also see I put a lot of duct tape on the connections as I was paranoid about any air leaks because the 90 degree elbows were the metal ones that you could actually twist for the best angle.  You have my permission to post these on your site and on Woodnet if you want as it was your design in the first place and I thank you for it.

Aloha,
Rob

This was received via E-Mail from Robert in Hawaii.  Hopefully Robert will share his future observations as he uses it some more.

Background: My shop is in my basement. I have a Ryobi BT3K, a small Inca (8-5/8" wide but short bed) jointer/planer, Inca 9-1/2" bandsaw, A Ridgid oscillating belt sander, and a router table with downdraft box. I use a Ridgid shop vac with 2-1/2" flex hose network for "dust" collection (along with a separator).

All my tools have 2-1/2" or smaller ports. I have a couple of different dust collectors but I don't use them because I just can't run 4" piping (perhaps some day I will figure out a way to do this--my shop is TINY). My shop vac gets about 150-160 CFM w/o separator. With the separator and network I get about 125-CFM. Absolutely not enough for collection of fine dust.

So the more I read Bill Pentz's site (among others) the more concerned I've gotten that I'm breathing boxcar loads of super-fine dust. That, this dust never settles and every time I enter the shop I breath more of it.

I realize my setup is sub-optimum, but the question is, how much of a price am I paying for it?

Recently I stumbled upon a particle counter that is really geared towards homeowners. It uses a laser to count particles in two sizes.

From the manual:

Quote"Small particles are all particles detected by the DC1100 right down to its detection limit--typically below 1-micron. Large particles are all particles detected above the large particle threshold which is typically around 5 microns."

The meter comes with a table to help interpret the readings:

Quote
0 - 25 Excellent Air Quality
25 - 50 Very Good
50 - 100 Good
100 - 350 Fair
350 - 1000 Poor
1000 + Very Poor

So I got this thing and plugged it in in my basement and let it settle for a half hour or so. I had not used any tools for at least 24-hours.

On returning to the shop, it was reading 53/4. You have to add "00" to the end of the readings, so 53/4 translates to 5300 particles total (per cubic foot), with 400 of them being larger than about 5 microns. So far, so good (looking at the table my reading was considered good).

So I switched on the vac and started to cut some MDF. I basically cut the edge off a 3/4" thick piece of 24" long MDF, taking about six swipes. This type of cut (where the blade isn't buried in the wood but rather the left edge of the blade is exposed) seems to generate the largest amount of visible dust above the saw.

I then switched off the saw and watched the meter spike. Approx. one minute after I was done cutting, the meter hit a max of 1955/515. So 195,500 particles (down to 1-micron) and 51,500 larger than 5.0 microns. Nearly twice the 1000+ reading that garners a "poor" rating from their table.

Subsequent readings:
+3 minutes (from peak): 1001/223
+9 minutes (from peak): 499/91
+46 minutes (from peak): 54/2 (now, it could have been low for a while, I had to go upstairs and wasn't paying super-close attention to the meter).

I'm taking for granted that the meter does, in fact, measure down to under 1-micron. However, I will say that the meter is extremely sensitive. Just moving around in the area (within six feet of the meter) causes readings to climb.

Some interesting factors: Above the saw is a vent from the furnace. The furnace has a Honeywell electronic air cleaner. When I close this vent, and let the [new] fine dust air cleaner (down to .3-micron) filter run for just fifteen or so minutes, the meter gets down to 18/1. With the vent reopened the meter almost immediately climbs to 50ish/3-4ish. So my take on this is that, with the vent open, the air from the rest of the house dilutes the super dirty air the table saw creates as I cut. So after cutting the #'s peak, but then fairly quickly start to drop again.

It is too early to make any real generalizations. I hope to use the meter to improve dust collection/filtering in my shop, home, and office (where we service PC's that are full of dust--similar issues to home wood shop).

BTW, the black thing is the meter, the big thing sitting on the floor is my new fine air filter.

Some time ago I purchased one of those little Harbor Freight mini portable dust collectors.  I got a helluva deal on it ($70 after stacking some discounts).  It is this one:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=94029

It sat unused for a while because I was pretty happy with my Ridgid vac-based cyclone.

HF claims 914-CFM and 9.4" of SP.  We know that the CFM is nonsense, though.  It has a single 4" inlet.  According to BP a 4" pipe can carry about 400-CFM.  My somewhat scientific testing (using two different anemometers) seems to indicate that this unit pulls about 370-CFM.

This unit is only twenty pounds but achieves some pretty impressive specs by using a universal motor spinning a small airfoil type impeller at 6400-RPM (typical DC's use radial impellers spinning at half that speed).

So I decided I'd build a larger cyclone separator and start using it.  I started w/ a 30-gallon can and an MDF top.  Added 4" fittings and my baffle and did some additional testing.  I was happy to discover that adding the cyclone lid only causes an 18% hit to my CFM.  That is pretty spectacular by cyclone standards.

I also had a chance to try connecting the entire assembly to my router table's downdraft box.  I had to do this with a 2.25" reducer to a 2.25" hose, so NOT optimum.  I was stunned to discover that airflow through the tiny (1.5"?) aperture in my router lift was sucking plenty of air.  I had always imagined that real dust collectors would have difficulty moving air through such small holes, but this clearly isn't so, plenty of SP here.

I did limited testing with actual dust because I only have the stock (30-micron) bag filter for the DC at this time.  It was able to separate 98.7% (by weight) of the dust I fed it (mostly fines from machining MDF and hardboard).  It was perhaps a little better but I did have difficulty gathering all the dust from the garbage can when I was done with the test.

I had previously posted that the DC is noisy.  It still is.  Part of that is the noise form the air movement, but certainly part of it is the universal motor, too.  Still impressed with what a $70 machine can do, though.  While this still doesn't provide the 600-800 CFM that some say is needed for fines collection, it is providing over twice the CFM of my current solution and is still compact enough to use, so it will become my new DC until I can make my giant separator lid with 6" outlet and twin 4" inlets, and run 6" PVC to my tools (yeah, right).

One common question I get is, "how do you make your circles."  I've just posted a preliminary page with instructions on my Thien Router Table Circle Jig.  This jig was born from a need for lots of large, [preferably] perfect circles.

To make my cyclone tops, I check the diameter of my target garbage can across three different axes (they are never perfectly round).  I average these together and make my top that size.  Then I use a rabbeting bit to cut a relief (notch) so the top sits down into the can about 1/4".  The fact that the cans are always a little less than perfectly round allows the top to "snap" into the can (basically the top brings the can into round).

http://www.jpthien.com/jpthien/cj.htm

Someone E-Mailed today and asked what the baffle itself was made of.  It is 1/8" tempered hardboard.  This is smooth both sides, and is quite slick.

Due to the nature of the material (dark color, produces lots of fines when machined) hardboard also works great for testing separation efficiency.   ;D

Got the following E-Mail form a guy named Rich:

*****
In a magazine test some time ago they used chalk to test filter efficiency.  You could do the same thing with your cyclone separator.  Add a couple tablespoons of chalk to your intake and run the vac for a minute or two.  Then see how much dust stays in the cyclone can and how much gets to the vac.  Don't use too much, it can clog filters badly.  -Rich

*****

I thought it was a neat idea so I took some bright pink chalk and sanded it with 150 sandpaper.  I created approx. 2 tablespoons of powder and then poured it into the cyclone's intake.

I've included a few pics below w/ results.

After performing the test and removing the hoses, I noticed a little chalk in the exhaust port.  I figured most of it had snuck through.  But upon further examination I was pleasantly surprised to see that most of it stayed in the cyclone (garbage) can.  The walls of the can, below the baffle, had a thin pink coating.  And the debris that was already in the bottom of the can had a thicker pink coating.

I don't know that this test tells me much, but I feel better with the chalk in the can than I would if the chalk ended-up in the vac. :D

Q: I read about the idea of expanding your design to 4" hose sizes, implying use with a fullsize dust collector.  I read about the problems you were trying to solve - but all of these were manifested with shop vac -2.5" size implementations. I do not think the carrryover problem you solved exists with larger scale dust collector solutions.  The traditional trashcan solution for a fullsize dust collector uses 4" hoses and a 30 gallon trash can, which is considerably taller than the 10 gallon can you used.  I have used a 30 gallon trashcan with a homemade lid and a 2 hp Jet dust collector for years. I never experienced the carryover problem you mentioned.  My lid looked just like yours, except it has no baffle.  I suspect it works as well as it does because its so much deeper and a larger diameter.

A:  Thanks Bob.  Interesting observations.  I have personally witnessed horrific scrubbing in shops I've visited, even with the 30-gallon cans.  Many people I know only use the cans with their planers because they can't keep anything smaller than very large chips in their cans.  But I will do testing w/ and w/o the baffle when I finish building my larger model.

*****
Q:  That looks great for a shopvac to keep the drum from filling up as fast. That sort of design typically doesn't scale well to larger collectors if the goal is to separate out the fine dust. Once you start moving more air the physical size required makes this design impractical. This is the reason for the popularity of the cyclone--done right it can separate out a large percentage of even the very fine particles.

A:  My tests indicate that my design scales infinitely better than designs w/ no baffle. I'm trying to apply the 90-10 rule. That is, I'm trying to provide 90% of the performance of a true cyclone for 10% (actually, a lot less) of the cost and complexity (and size). I make no claims of outperforming or even being the equal of a large Torit cyclone.

We lost a few messages when I decided to change forum software (to make registering easier and photo uploads possible).  So here is a recap:

*****
Rick:  The baffel has a 240 degree by 1.125 relief.  What is the relationship between the elbow outlet and the 240 degree cut out?

JPT:  The elbow is under the portion of the baffle that is not relieved.  My tests have shown that the baffle should be placed so the back of the elbow is aligned with the beginning of the larger radius.

*****
fishnskiguy:  Neat design, I'm impressed!

My question is similar to Rick's.  I'm having a very hard time orienting the inlet elbow with the baffle.  As I understand your reply to Rick, a particle of dust would exit the elbow and then travels along the entire 120 degree portion of the baffle that is tight to the can, and then reaches the beginning of the 240 degree 1.25 inch relief, and then drops into the can somewhere along this 240 degree section.  Do I have this correct?  A drawing or photo showing the location and direction of the elbow relative to the baffle would be a big help.

JPT:  You are nearly correct, except the 120-degree portion starts back at the bend of the elbow.  So the particle travels along all but approx. 2" of the 120-degree portion.  I found this design worked best to reduce turbulence at this critical point.

*****
fshagan:  Love the design of this...simple and elegant.

How large have you scaled it up?  I'm wondering if the limiting factor to using it with a shop vac is the diameter of the container rather than the overall size...if you could find a taller can that is the same diameter you might be able to increase the capacity without losing any performance.

JPT:  I don't have a single tool with a 4" port on it.  I have a Ryobi BT3K table saw (heavily modded) w/ a 2.5" port, a home-built router table with down-draft box (2.5" port), and Inca jointer/planer (2.5"), and an Inca bandsaw (1.5" port).  All in a tiny basement.  The shop vac is my friend.  :)  Perhaps a dust collector would work better w/ the table saw (even through the 2.5" port), but it would certainly work worse with the router table's down-draft box.

I did make a 20-gallon version w/ 4" in and out.  I tested it a little bit with someone else's blower for a couple of days in my shop and it worked great.  I rigged it so the blower sucked the can, and blew a cloth (1-micron) filter bag.

That was approx. six months ago.  At that time I thought a nice system would be a 30-gallon can with two 4" inputs (on opposite sides of the top) and a single 6" output.  That output would connect to a 1.5-2-HP blower motor, which would push into a large cart. filter like you see on the tops of nicer Jet and Delta single stage collectors.  I would rig the filter in such a way that there would be a clean-out on the bottom (much like large cyclones have on their filter stacks.  You could probably assemble an entire system like that for under $250 if you carefully assembled the parts of eBay/craigslist.

To answer your other question, the taller the can (provided you have the room) the better.  Or at least, the taller the can the more it will hold (someone has to lift it when it is time to empty.   :o)

The diameter of the can does affect the performance.  Too large and the baffle will never be cleared of the debris.  That is the worst case scenario.  Too small is a problem, too, as things can spin too fast to settle from the stream.  HOWEVER, in spending the last couple of years observing these things working, I'm amazed how quickly even the finger material will escape.

Many people have asked questions in the forums where I make my initial announcements. That is fine, but I thought I would recap answers here to avoid overlap.

*****
Q: Length of video is too long.
A: I agree, I'll do something about that. I was worried that if I edited it people may feel light there was some slight of hand.

*****
Q: Could you add the baffle to an existing design like the Lee Valley that has the exit port in the center.
A: Results less than optimum because of the angles of these ports. Really need more typical cyclone alignment. Don't get me wrong, the baffle will help the LV, just won't be optimum.

*****
Q: If you suck up the pile as fast as you can [in the video], does the filter still stay clean?
A: EXCELLENT question. There are two things you don't want to do to a cyclone: (1) Stuff it (where you feed it too much debris and too little air) and, (2) Starve it (where you feed it little debris but little air, too).

If I do a full seven gallon stuffin of my cyclone (feeding the entire seven gallons in what I approximate as 1.5 minutes or less--I've never timed it), probably about a cup of debris will make it to the vac.

Of course, full cyclones are not immune to this either.

The answer is that the entrained particles have to be entrained (in air) to be separated. If there is no air, there is no separation.

*****
Q: Very impressive. How does the cyclone do with extreme fines, like you get using your random orbit sander, or a drum sander? I would be interested in making one as I'm tired of beating the squat out of my filter to knock the dust out of it. Please keep us appraised of the larger size tests, this might be the ticket for my drum sander with my HF dust collector.

A: It would certainly help but in reality I've read complaints even from people with full-blown cyclones that have not been satisfied w/ performance on their drum sanders. If I can get some interest I may try to find a volunteer in the Milwaukee area w/ a drum sander where I can do some testing.

I have done testing w/ orbital sanders and have been happy with the results as long as I make sure I don't starve the cyclone. The 1" hose I have for my Porter Cable sander is okay. But I always open another blast gate a little to make sure the cyclone has enough air to perform separation.

*****
Q: I assume there's something special about the angle of the inlet as well as its placement? What's that wing-nut looking thing in the middle of the baffle?

A: The placement of the inlet is somewhat of a compromise no matter what we do. That is because the ideal placement would be a tangent to side of the can, but given the size of the inlet and other obstacles, the best we can hope to achieve is to get the inlet close enough to the side that it somewhat gracefully eases the incoming air into a circular rotation in the can.

The wingnut is just there to cover the 1/4" hole in the center of the baffle that is a remnant of the circle cutting jig I used to make it.

*****
Q: I use the cyclone system but it is the small pail size. As an amateur who doesn't run the shop every day, at least not the sawdust making machinery, this seems to be all I need. So, how will this work with this size? It appears reasonably straightforward to build, but your lid will cut down on the available space inside. Should I go to a larger size can?

A: The baffle reduces the capacity of my 10-gallon steel garbage can by approx. 2.5 gallons. If you can live with approx. 7 gallons of capacity (quite a bit for the average part-time home woodworker), I'd say to just use the 10-gallon can. Otherwise it can be ramped up, but there is a limit (we need enough CFM to enduce full rotation and therefor adequate separation).

*****
Q: Phil, that is awesome. Do you think a similar one would work if you used smaller pipes and a five gallon bucket and ran it with a shopvac? And did you do anything to ensure that the cyclone lid was snug against the trash can? How did you avoid leaks?

A: This small model I demo actually is used w/ a shop vac. I used a ten gallon steel garbage can, which really isn't that much larger than a 5-gallon pail. You might be able to squeeze the design into a smaller 5-gallon pail, but the performance would probably suffer a little unless (like you mentioned) you reduced pipe diameter accordingly.

There is another reason to avoid plastic pails, though. And that is to avoid static problems. I'm not concerned with the chance of explosion, but rather have noticed that static charged plastic can interfere with the operation of the cyclone.

The tops I've made during have been of MDF and sometimes (when I've got scraps that are large enough) baltic birch. I cut a lip on the plywood and it "snaps" down into the steel can quite nicely. No leaks, and I don't use any weather stripping.

A special thanks to Frank Hagan over at sawmillcreek.org for suggesting I switch forum software from phpbb to SMF.  The phpbb software posed a number of challenges that the SMF software seems to alleviate.

I apologize to posters that will have to re-subscribe, but at least we'll have an easy way to upload pictures and graphs now, and new users will find signing-up a lot easier.