Thien on a dime!

[Salty]

Well, a little more than a dime...but not much.
All I can say is WOW...I should have done this a long time ago.
I am thoroughly and completely impressed and amazed at how well this works.
After I got a close 90 degree ell and sealed up some leaks it works great. There are still some leaks that will be resolved when I get some 2” hose and fittings.
If I have $5 in the whole thing I’d be surprised.
I used the plastic lid that was on the 5 gal driveway coating bucket. I am wondering if perhaps the ribs on the underside of that lid may be causing some undesired turbulence. If so, it doesn’t seem to be enough to bother the performance. My last test was to vacuum up a variety of carpet yarn, sawdust, paper and wood chips. Only a pinch of dust was in the shop vac, no large stuff. That is exactly what I was shooting for. With a paper filter bag in the vac I will have my working collector system.
Salty

[crokett]

So that works on a 5 gal bucket? I have a kit that was supposed to work with a 5 gal bucket but the air doesn't slow down enough to let stuff fall out of it. Maybe if I modify it and add the baffle it would.

[dbhost]

The Thien baffle is only half of the equation. Many of the lids have a port on each side, instead of inlet on one side, and outlet to the vac in the middle. The middle of the bucket is where the air is slowest and should have dropped its load...

[Salty]

The Thein design seems to be somewhat forgiving. I'm sure I could tweak this and make it perform even better. I could notch the edge of the elbow and move it even closer to the sidewall. I was not exact in the placement of the 120 degree section and it does not fit exactly tight to the inside of the bucket.
That is an interesting note about the air at the center being slower. Much of the theory was missing from the websites I researched this on.
But it performs admirably in that ALL of the heavier solids were deposited in the bucket.
I was thinking of finding a larger container and making this bigger. But why? I can lift a half full 5 gal bucket of sawdust much easier than a half full 30 gallon drum. If my shop was bigger and had more tools I would be tempted to do so, but this is a small scale shop.
I am anxious to see how much more of the full vacuum I get with better hoses.

[LinuxRandal]

Does the lid have its o-ring?

[Garasaki]

The Thien baffle is only half of the equation. Many of the lids have a port on each side, instead of inlet on one side, and outlet to the vac in the middle. The middle of the bucket is where the air is slowest and should have dropped its load...

I would disagree with that.

Rather, I would disagree with the "the middle of the bucket is where....should have dropped it's load".

I believe the physics of this is that the airstream "whirls" around the edge of the container, then changes direction to go up thru the outlet pipe in the middle.

The air has very little mass, therefore very little momentum. It can change direction without a large loss of energy. It also is not greatly affected by the pull of gravity.

Woodchips in the airstream have much more momentum. They will resist changing direction and instead "flow" to the edge of the container. When they reach the edge, friction with the edge of the container slows them down, and gravity pulls them out of the airstream while the actual airstream will swirl around the pull up thru the outlet tube.

I think it has very little to do with the speed of the air. After all, with the thein separator, material falling out in the middle makes no sense - that's where the plywood is, so it would end up sitting on the plywood.

That's my own personal opinion of the physics involved - the centrifigual swirl of the air pushes the particals to the outside, while the air stream exits the enclosure in the center.

I have a thein separator on a 30 gallon trash can hooked up to an HF DC, and I am super impressed with it's performance. I had to do a lot of tweaking to get it to be this effective though. I will eventually get some pictures of it posted.

In the OP's case, I say if you are happy with it, why bother tweaking it??

[Salty]

Does the lid have its o-ring?

Yes, the o-ring is intact. That makes the lid airtight but there are some leaks around the fittings.
And, I have 2 or 3 more of these buckets and will have about 5 more later next year!
I may also rework it with a piece of thin board on the underside of the lid. That will eliminate any drag in the airstream at the top of the chamber.

[Salty]

OK, made some changes. I mounted a piece of melamine board on the bottom side of the lid. Moved the elbow closer to the side and skinned it down to be closer to the sidewall. Now if my new hose and fittings ever get here I'll find something to make sawdust with and see how well it works.

Salty

[crokett]

The Thien baffle is only half of the equation. Many of the lids have a port on each side, instead of inlet on one side, and outlet to the vac in the middle. The middle of the bucket is where the air is slowest and should have dropped its load...

No this one has the outlet to the vac in the middle. I just figured that he bucket wasn't big enough and air wasn't slowing down enough. I will look into a baffle at some point. I would do a bigger bucket for sawdust than a 5gal pal because it holds more and I would not have to empty it as often.

[pecker]

Has anybody used one of these things for water pickup?
I wouldn't be using the Thien baffle for this...just the lid and 5 gallon bucket.

When I get the occasional water in the basement, it would be nice not to have to first empty the 16gal shop vac, remove the filter, suck up the water, then try to lift that bulky, heavy thing up to the sink to empty it. Being able to just insert the bucket with lid into the collection hose and start sucking up water would be great. (I realize I'd have to be careful not to let the bucket fill so much that the vac started sucking in H2O.)