My delta 50-760, 55gal top hat complete.

[juicegoose]

Well it took me long enough but I finally finished my top hat design built on a 55gal drum. The drum had a locking lid ring and I made sure to use that ring to secure the top hat on the drum. all pipe was 6" and material was a mix of ply and hardboard and 1/8" clear lexan. I'll let the pictures speak for themselves.
First I modified my Delta 50-760 to have a 6" inlet
I then created a template  for the drum so that the lip of hardboard would slide under the locking ring. From there I built up the circles for the bottom, dry and test if everything and then put it all together.
The result works great for keeping the tophat centered.
I have found that it doesn't do a good job with fine dust but I think that might be a result of the following items
1. not a tight seal on the system
2. drop slot location and width(measured to be 1.5" wide)
3. Thickness of baffle  even though I tapered it back.

[juicegoose]

2 more of it complete and with the window in the drum.

[Bulldog8]

Separating fines is the reason I built my first Thien baffle. I was plagued with clogged bags when running a drum sander.

It looks like your drop slot is more than 240 degrees. That may allow too must air to swirl below the baffle not letting it settle out.

The thick baffle definitely doesn't help. You could cut your thick baffle back even further to use as a support and then add a thinner baffle plate to decrease the baffle thickness and decrease the size of the drop slot.

Raising your inlet pipe and/or going from round to rectangular will also help.

[juicegoose]

What you mean by raising my inlet pipe or changing to a rectangle?

[Bulldog8]

You have a 6" inlet and what looks like about 2" above and below the inlet, about a 10" tall chamber. Normally, the outlet pipe would be 1/2 d (3") down from the top of the top hat. Yours looks deeper, which is a good thing with the tall chamber.

So if you raised your inlet port as high as possible (about 1/2") down from the top, incoming air and dust would have to move downward to the exit pipe. This downward movement in conjunction with the circular motion of the incoming air stream gets the dust moving in the desired direction. (to the collection barrel)

An inlet pipe that transitions from round to rectangular as it enters the top hat causes the velocity to drop somewhat and keeps the air stream against the chamber wall.

Here are pictures of my first and second top hat. Both have a 6" inlet pipe. The chamber height of the first was just barely enough to fit the 6" inlet, the second has a tall chamber with a deep outlet. I've also bent the round inlet pipe into a rectangle shape. Others have done a better job in the round to rectangle transition. If I ever rebuild it, I'll make the rectangle even taller and thinner. I had good separation with the first one, but was intrigued with reports of success with fines with the "tall chamber" variant. The tall chamber works well with my tools. Bother my planer and jointer have Byrd heads so I don't get large chips of anything. Before I had the Byrd head on the planer, I had fairly large shavings with some woods and suspect that the tall chamber might not have handled them as well as it does the finer dust.

[juicegoose]

Thanks for the reply. I've got a lot of things to do to get the system running right.
I did put a piece of wood at an angle from right under the inlet pipe until it meets the circular chamber. I was finding that as dust entered the rectangular portion of the inlet it was getting caught in some vortex right below the inlet pipe.

[juicegoose]

Well yesterday I measured some items and made some modifications. Seemed to help a lot.

First I measured the baffle length I was more like 270-300 degrees so what I did was place a piece of hardboard inside the baffle right at the inlet. I scribed it to the outside edge and then tapered the exposed edges before gluing it down.

Second, I measured the distance of the outlet pipe from the baffle plate and then put an extension on the pipe to get it closer to 3".

Third, I sealed up the lock ring that holds the top hat to the drum. I used some 3/4" wide 5/16 thick weather stripping. Worked well.

Forth,  I put in a 30 degree angled plate at the inlet so that the incoming dust is sent toward the outer wall immediately.

Finally I moved the inlet pipe up as far I could.

This all seemed to help a lot. I need to clean out the filter empty the bin and test it again but it seems to be much better.

I think part of why i'm getting so much fines as well is that while I'm testing I'm basically taking a 4" hose and shoving it in a large pile of fine sawdust. That is a tremendous amount of dust at one time.

[alan m]

all of that should help a lot.
post a few new pics  for everyone to see.
shoving the hose into a pile of dust will overpower the system and allow a lot of bypass. if you feed the dust slowly you will see a big improvment

[Bulldog8]

That sounds really good. I agree that you should clean out your filters and then give it a real world test of a day or two of woodworking. After that blow the filter down and see how many fines you get. If your happy with the amount of fines that made it to the filter you are all set. Nothing will keep all the fines out, so once you get the performance that led you to building the separator in the first place you are set.

Steve

[juicegoose]

I took the opportunity over the weekend to clean out my filter and at the same time route back the baffle thickness. I also got some pictures of the diverter. After cleaning the filter out and slowly sucking up a pile of dust I still noticed some bypass but I still think it was a result of super fine dust and lots of it. I completed a wood working project and noticed little to no dust into the bag so I think it's working. I'm going to clean out the filter again and let it roll for a bit.
Here are a couple of pictures of the piece of wood I put in to help get the material to the outside edge as quick as possible. I think it also helps keep the initial pass of dust from the inlet to not pass to close to the outlet and get sucked up the hose.