I am going to build a separator for my new DC unit. I bought a 30 gallon metal trashcan -- like the one in Stugots recent post. I am going to use 6 inch ducts from my DC to my tools. Is there any reason why I would not want to use 6 inch ports on the separator?
Thanks.
Ray
I see no reason as why not ... more air flow the better (within reason).
I guess I am wondering if there will be enough room in the lid space for two 6 inch connectors and if that will negatively impact the performance -- having such large inlets and outlets.
A 6" inlet with a 6" outlet centered means you have a min of 9" radius which puts the inlet right beside the the outlet. Solution are to make the baffle wider (if you can accomodate it) or to put the inlet on the side of the baffle instead of the top
There are a few people who have built baffles using 6" inlets/outlets (including Greg) so take a look at the previous posts on this forum.
I would put the inlet on the side like others have. You reduce the number of twists and turns the airflow has to take, and save room too.
Can anyone offer advice on how to cut into the side of the trash can and place an inlet in the side of the can effectively? For the actual inlet "piece" I guess I can use a straight tube and cut away (on an angle) the part that will be on the inside of the can.
Quote from: rsquest on December 22, 2008, 11:14:44 AM
Can anyone offer advice on how to cut into the side of the trash can and place an inlet in the side of the can effectively? For the actual inlet "piece" I guess I can use a straight tube and cut away (on an angle) the part that will be on the inside of the can.
Here is a link to a thread where there is software discussed that will plot a template you use to cut the garbage can. Basically, you provide the diameter of the can, the diameter of the inlet, and the angle of entry, and it does the rest.
http://www.jpthien.com/smf/index.php?topic=36.0
So basically, you'd mark the template on the can, and use a Dremel or something similar to cut it out. Then you'd tab and fold-back the inlet pipe, and either solder or rivet it to the can.
Let us see some pics when you're done.
This is a little intimidating to me, but I have learned so much in the past year ... I guess I can try to tackle this! I don't have any soldering or riveting equipment, but I will figure out something. I guess I could use small bolts and washers instead of rivets ... some silicon could to get a good seal ... that may work. I have never done any kind of metal working, but I suppose that as long as I am careful about the sharp edges I can figure it out.
As I think about this ... what I might do ... buy a piece of 6 inch PVC, cut a hole for it to fit through -- coming in on a tangent, extend the PVC tube into the trash can just far enough that I can put a bolt through the can and PVC to hold it in place. Inside the can, the PVC will be cut at an angle so that it just minimally impacts the area in the baffle. I can use caulk to seal around the PVC. I don't know if this makes sense, but I think I am going to try it (unless someone describes an easier way to accomplish this).
Trying to use the software for drawing the diagram for the hole that must be cut ... I think that I want to use:
Join angle: 90 degrees
Main pipe exterior: This would be the diameter of the trash can
Branch pipe exterior: This would be the exterior of the PVC or whatever I use
Thickness: thickness of the branch pipe material
Lateral offset: -- this is the one that I am not sure of. I think this should be the maximum that it allows.
I would have the pipe come in at as much of a tangent to the outside of the can as you can.
As for metal working, you can probably cut into a trash can by drilling a starter hole and using tin snips. No big investment in equipment. Also I bought a $20 pop rivet kit from the BORG and keep finding uses for it! Real simple to use, let me know if you need help. They are nice cause they sit flush!! Go for it man, nothing to be intimidated by.
So my intake on the DC is 5 inches ... so I am wondering if it is worth putting 6 inch on the separator or if 5 inches would be better. Going for 6 inches will take up more space from the trash can.
I have been planning to use 6 inch on all of my runs to my machines. I am not an engineer and don't really understand the fluid mechanics involved here. Will going from a 5 inch DC intake and up-sizing to 6 inch help or hurt my dust collection? ... or will it have no effect? I know that it is hard to find 5 inch pipes, but I think there is an irrigation supply nearby who will have it if I try to go that way.
5" pipes/fittings can be kinda tricky to find. The 4"/6" stuff is much more common. I'd probably size the separator to 6", and maybe consider a new blower some day down the road that has a 6" inlet.
The idea of extending the PVC into the can and securing w/ a machine screw has occurred to me in the past. BUT, having it extend into the can would make it difficult to install the top w/ the baffle. If you're going to extend the PVC into the can, you're probably going to want a way to install the baffle separately from the top, so you can maneuver it around the inlet.
So, as I posted in a separate thread, I am going to use an A/C duct. I guess I will try to use some rivets to connect it, but I am looking for additional ideas on how to get a good seal all the way around.
Quote from: rsquest on January 07, 2009, 04:23:31 PM
So, as I posted in a separate thread, I am going to use an A/C duct. I guess I will try to use some rivets to connect it, but I am looking for additional ideas on how to get a good seal all the way around.
You could always use something like silicone. I had thought about solder, but doing so would probably result in having no rust protection left on that area of the can/pipe.
I am right in the middle of doing this right now. I am using a 30 gallon can. I chose 5" round galvanized for both the inlet and outlet. I have never really done metal work, so this is taking me a bit of time to assemble, and it is looking a little rough. I used the pipe angle calculator mentioned earlier to have the pipe go directly in from the side of the can - i do have it protruding in, and plan to mount the baffle (not made yet) separately from the lid. I am also mounting it directly below the inlet on the 50-760. I will grab some pictures of the progress tonight.
one question though. how far below the inlet and outlet should the baffle be? I have seen some pics here where it is mounted directly below the inlet, and some where it is a bit further away.
Quote from: backsaw13 on January 08, 2009, 07:16:10 AM
I will grab some pictures of the progress tonight.
As promissed:
(http://backsaw13.smugmug.com/photos/451546502_9aeYa-Th.jpg)
(http://backsaw13.smugmug.com/photos/451546374_nWkoG-Th.jpg)
(http://backsaw13.smugmug.com/photos/451546781_4P7Us-Th.jpg)
(http://backsaw13.smugmug.com/photos/451546907_yNKJj-Th.jpg)
This last picture shows that the can gets propped up to meet the lid which will be attached to the dc inlet. The can will drop down to be emptied. I am still thinking of an easy way to raise and lower the can. Also, the cross member on the legs of the DC may need to be removed, as it is difficult to maneuver the can in and out of place.
I still need to create the baffle. I will mount a couple support brackets along the flush portion of the baffle to attach to the side of the can. I will also add a vertical support that will extend from the baffle to the bottom of the can.
I am having problems posting ... it seems that my picture is too big. Phil, Maybe I could send my pictures to you and you could post them.
Here is my progress. I used the A/C duct that I mentioned earlier. I cut the trash can with my Dremel. I used tin snips to cut the duct so that I could bend it and shape it to the trash can. I used a hammer to bend the duct to the shape of the circumference of the trash can. I used door/window sealing strips to get a good seal between the trash can and the duct and used rivets to attach the duct. I used washers with the rivets -- on both sides -- to get extra surface area on the attachment. I was very suprised at how strong and rigid the connection is.
I have two steps remaining:
1. Attach new dowels to the baffle -- the current ones are too thin to give good support strength, and the new ones have to be adjusted in length for the depth of the inlet.
2. I have to get and install a 5 inch A/C pipe into the top of the baffle.
I should be able to do both of those things this weekend, so I hope to be sucking sawdust by EOD tomorrow!
Ray
Quote from: rsquest on January 10, 2009, 01:26:42 PM
I should be able to do both of those things this weekend, so I hope to be sucking sawdust by EOD tomorrow!
Ray
Yep, I'll resize and post the pictures for ya.
I've already seen pics at sawmillcreek. It really looks outstanding.
If you transition to rectangular before the entrance it will make the hole a LOT easier to cut with a good fit.
...lew...( use to do a little HVAC work ) :-)
Another senior moment.
Okay, I'll say it, I don't quite understand what you mean.
Can you explain it a little better, because
I'll be attempting the same thing as soon as I can purchase the parts.
Thanks,
Deb
Deb,
I am not sure what you don't understand, and if you are saying that to me or someone else.
The part that I don't think you understand is the rectangular piece. When Phil gets the pictures up for me, it will probably be more evident, but I will try to explain.
I used a floor duct ... the kind that is a tube at one end, takes a 90 degree turn and is a rectangle at the other The long axis of the rectangle is the same as the long axis of the cylinder. I used the rectangle end to attach to the trash can.
I will wait for the pictures and for your response to see if you still have questions.
Ray
Quote from: Lew Hartswick on January 11, 2009, 09:35:19 AM
If you transition to rectangular before the entrance it will make the hole a LOT easier to cut with a good fit.
...lew...( use to do a little HVAC work ) :-)
I didn't quite understand what Lew meant by the above.
Yeah, I guess I don't understand either. ... the piece I installed did transition to rectangular before the entrance.
I am currently building a baffle top for my trash can, and the pictures might clarify the idea of converting from a round duct to a rectangular one for entry into the cyclone chamber. The one thing that I did wrong was assuming that I would have the same cross sectional area in the rectangular end as on the round end. I had forgotten that although the perimeter is the same, the area is not. The result was going from a 6" round (28 sq. in.) to a 7" x 2.5" rectangle (17.5 sq. in.). Since I will be reducing the 6" duct to a 4" one to connect to my existing system, I decided to proceed. If I later decide to go to a 6" duct system, I will have to increase the size of my rectangular end.
To accomplish the transition, I decided to make one dimension 7" and cut some pieces of MDF to 7" x 10", and stuffed them into one end of the 6" duct and gently hammered the square corners in. I screwed through the duct to the boards with short sheet metal screws to hold them in place, and sealed the holes later. After getting two 7" wide boards in, and fastening them to opposite sides of the duct, and beginning to hammer out the corners, I forced in some smaller pieces of MDF so I had 3 widths in the hole. (I could have used a single 7" wide piece here). Then, with only a little ways to go, I hammered in wooden (or plastic) shim stock to force the duct out to the final width, and finished hammering the square corners. The it was time to remove the screws and force the MDF forms out of the hole.
To determine the size and placement of the opening in the round chamber, I just sort of eyeballed where I wanted the duct to go, drew some lines, and cut out an opening, leaving tabs for fastening, using a dremel cutoff wheel (actually several, as the wear down quickly, and shatter easily if they get caught in the kerf :-[.
I attached the duct with pop rivets, and sealed the joints with silicone. I taped over the screw holes with 3M metal tape (perhaps find it at auto supplies that cater to body shops?).
Here are some pictures that I hope will clarify things. Sorry I did not document the forming process.
RBOETTCHER,
I like what you have done so far. Looks great.
More pics as you get farther along....
Quote from: rsquest on January 12, 2009, 09:34:35 AM
Yeah, I guess I don't understand either. ... the piece I installed did transition to rectangular before the entrance.
That is one way to do the transition. Just what I meant. You just said it was 6" round duct before.
The other way would be a round to square "adaptor" in the piping just as it comes to the can.
...lew...