J. Phil Thien's Projects

It took a while but I have it made (almost). My dyslexia kicked in and I ended up with the inlet being opposite of what I intended. While alan m indicated that in practice it doesn't matter; it does matter in my shop so I'll have to do some modifications. I did hook this up to the blower just to see how it worked (not bad, considering all the air leaks)

Testing raised another question.

I understand it is important for the top hat to be "sealed" to the collecting drum. I plan to use foam window insulation material a a seal. Is the weight of the top hat enough to create a good seal or should I create a clamping system to hold the two parts firmly together?

Thank you for your input, retired2. When I started reading posts, it didn't take me long to realized that you are one of, if not the most respected contributor to this site; so I really appreciate you taking time to reply to my post.

I made the inlet this morning. The 4 inch circular inlet transitions to 2.5 by 6 inch rectangular entrance. The transition length is 12 inches. (Picture attached, hopefully)

So by my math, I have an 8 in radius, 2.5 inches for the inlet, 2.5 radius for the outlet. This leaves 3 inches of space, not very much in my opinion.

I think I have a couple of options--go for it with this drum or find something with a larger diameter.

Thank you for your reply.

Would a taller top hat (for example 10-12 inches) help overcome the deficit of the small diameter of the drum?

I think i'll start with a 15 inch transition length.

Several years ago, I started to make a small top hat to sit on a 5-gallon bucket attached to my shop vac. When I talked with my brother about this project, he gave me a dust deputy he had, so I didn't make it. Fast forward several years and I have upgraded my table saw, bandsaw, etc. so I have several dust makers. To this end I am again planning to make a top hat collector.

I have read and re-read hundreds of posts over the years and gleaning from everyone's experiments and projects. My sincerest thanks to everyone that has added to my knowledge.

I think I have developed a plan but I have doubts about several parts of it.

I have a 2 HP Harbor Freight unit but with a larger impeller. I have a 35 gallon plastic drum (16 inch diameter, with 1/4"sides). I am planning a top hat with a 4" inlet and a 5" outlet.  The 4" inlet will transition to a rectangular opening 5.75" by 3". I am not planning a bellmouth at this time but I might add that in the future. (retired2's suggestions, but would a taller thinner opening be better)

So my questions:
Is a 16 inch diameter drum too small? I chose this drum because of the thick sides and light weight. (Question based on Post 369)
I think I would like to make an 8" tall top hat, with the inlet located towards the top as people have suggested the taller top deals with fine dust better.. Or, should I make it 6 inches tall and center the inlet?
How long should the transition from the 4" inlet to the rectangular opening be?
How far into the top hat should the outlet extend? I've read half the distance, but half of what distance, the top hat or the inlet?
Does it matter whether the inlet is on the right side or the left side?

My guess is that these questions have been asked and answered somewhere in the site but I haven't found them and would like to have input before I build.