Sunday, June 14, 2009

Making a Bucket Mounted Cyclone, part one

Here lately, I've been doing a lot work on the belt sander, which produces a lot of fine dust, which is collected by my shop vac, which in turn ends up with a clogged filter. Then I have to shut down what I'm doing, and clean the filter, which, of course, makes a bit more of a mess in the shop, as that fine dust just billows everywhere. The solution to this problem is something that takes the dust out of the airstream before the air passes through the filter. The best way to do this is with a cyclonic separator. There are at least three on the market that can be mounted on a five gallon bucket and used with a shop vac (one that is made by a well-known company, the other two I found by searching around on the web). The cheapest of these costs about sixty dollars, plus shipping. As a self-respecting tightwad, I just couldn't bring myself to pay this cost. I got to pondering my dillema, and the fact that I have all of this scrap material laying around taking up space, and decided that maybe I could make my own separator. Here's the story of what I did, and how it came out...

I've decided to keep it simple, and just make the body from layers of plywood rings. The board on the left is my initial layout- the conical body will be a little over ten inches high, with a 7 1/2" i.d. at the top, 3 1/2" i.d. at the bottom. (that was the intention, anyhow- it came out a bit different). The piece on the right is the layout for the first ring- note the entrance holes drilled for the scrollsaw blade. I had the scrollsaw table and drill press table set at the same angle to keep things simple.

I used each ring to lay out the next ring...


Here's the first three rings, with a bit of scrap to the right. They are assembled with the glue
and 18 guage brad nailer shown in the pic. I never thought I would enjoy having a brad nailer- doesn't seem like "proper woodworking". I have to admit, though, that for making shop projects like this, it has turned out to be unbelievably useful. Care must be taken to see that brads don't blow out into the interior of the body (of course, some did- I simply clipped them, then ground them flush with a dremel tool).

About the fifth level down, I decided to install this square ring. Despite how odd it looks, this turned out to be the smartest single thing I did in this project. A plain cone would make for very difficult work-holding, but having this one square piece made it quite easy. In later stages, I was able to simply clamp it to my bench with a c-clamp and perform heavy work on it. In use, if need be, I'll be able to secure bracing struts to this part.

Here's the completed cone. It looks good in this pic, but fact, it's all out of wack, and I spent a week trying to get it right with 36 grit sanding paper on a 1" dowel. I clamped it to the edge of my bench, and worked it with a motion like churning butter. It was way, WAY too much work- if I ever do this again, I'll work up some kind of angled router jig and use a flush cutting bit to make sure the rings are perfectly consistent with each other.

I need to drill a large hole at a tangent in the cone for the intake pipe. Here the square section is showing it's usefulness again- I just clamped a bit of scrap to the top, making sure that everying was sitting right.

I pondered a bit, and finally decided to use my biggest forstner bit to drill this hole (2 3/8", which turned out to be the perfect size, anyhow). I was a bit worried about it with the brads (something I should have thought of beforehand), but it turned out that they didn't cause a problem for this big bit. While forstner bits don't tend to catch, I wasn't taking any chances with this odd assembly, and clamped it all to the drill press table to do the work.

This is something you just can't do with any other kind of bit- the bit is cutting on only one edge, and tracking just fine.

More progress, and cutting through, now.

And here we have the hole drilled all the way in to the interior. I had placed it by eye, but it turned out to be in pretty much a perfect location.

Front view. The end of the pipe will fill most of that little flat spot, so it's not a big deal.

Just as I was about to go and buy some pvc pipe, I found a bit of it in a rollaway dumpster. One of the hotels on my route is remodeling, and I think this came off an old jacuzzi. It's just over 2 3/8" in diameter, which is why that drill bit was the perfect one to use.

Test fitting the pipe- note the fitting on the end- I cut that off later.

Here's the cut line, traced with a sharpie. Over to the bandsaw and big belt sander...

And here's the pipe cut and sanded to final shape. To install it, I drilled the pipe into the body, put in one screw, then used putty epoxy to fill in around it (yes, it was Mighty Putty- that's what I had handy). Later, I backfilled from the outside with low-viscosity epoxy, and then silicon sealer. It's strong, and doesn't leak.

I like to make hose connections for my shop tools with mdf- I didn't have to get into my stash for this project, as I found a bunch of the stuff sitting by a dumpster. I have no idea what shape was cut out of the one piece- matters not a bit to me.

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