J. Phil Thien's Projects

I built 2 Thien style separators a few years ago, both built on  20 gal (approximate) plastic barrels and worked fantastic.  One was used on a 1hp dust collector & the other on a Harbor Freight 2 hp dust collector (1550 cfm supposedly), like I said both worked great hardly anything got into the collection bags.  Two years ago I was flooded out in the flood of 2016 and lost both collectors, I have just got my workshop set up again & replaced the 2 hp HF with  a 3 hp Grizzly collector (2320 cfm), now the separator does not work nearly as well as it did with the 2 hp HF, a lot is ending up in the collection bags.
My question is, could the higher cfm of the 3 hp unit be too much for the 20 gal barrel?  Or what should I try?  Wondering if I made another separator with a 55 gal barrel, would the larger diameter barrel work better with the higher cfm of the 3 hp collector.  Hoping some of you more experienced guys that have played around with these a lot & made a lot of improvements might have some ideas and or suggestions.

I am building another Separator lid to be used just for my down draft portable sanding table and router and plan on making the drop slot 3/4" wide instead of 1 1/4".  Would that increase collection of fines, or be too small?  I know 3/4" is small but there will never be anything large going in this one, just sanding dust and chips from router.

Would a larger diameter barrel give better separation of fines (flour) in a Thien separator with the baffle attached to the lid (not a top hat)?  Thinking about building another and debating if it would be worth the extra space to use a 50 gal barrel instead of a 30 gal barrel, because space is limited in my small shop.

Is this forum still active?  I have not seen a new post for about 2 weeks now.

I want to make a top-hat and thinking about using 3/4" plywood for the top and bottom and cutting the slot in the bottom larger (like 280 degrees and 2"wide) then putting a piece of 1/8" hardboard over the bottom and cutting the proper size slot in the hard board (240 degrees and 3/4" wide) for very fine dust from my scroll saw.  My reason for wanting to do like this is to use the 3/4" to support the 1/8" so it does not sag, I would glue the 1/8" to the 3/4".  By making the slot in the 3/4 larger than the slot in the 1/8" my thinking is I will get the support I want for the 1/8" without the thickness of the 3/4" effecting the separation (slot will only be 1/8" thick.   Also I would be able to route a slot underneath the bottom 3/4" to seal to the barrel.  Is my thinking flawed or do you'll think this should work good?  Also I plan to use Formica for the side walls since I have it already, I would use the slick top side for the inside of the wall?  8)

Has anyone compared the efficiency of a top hat type Thien separator to a Thien separator with the baffle in the barrel?  Other than more capacity? :)

Currently I use flex hose from HF DC to Thien type separator and from the 4" PVC trunk line to separator.  Thinking about changing the flex hose to hard pipe and wondering if it is even worth the effort, I know & understand there is supposedly less resistance but the line from DC to separator is about 4' long and the one from trunk line to separator is also abt. 4'.  Also thinking that if I do this I would also change the line from DC to separator from 4" to 5" using metal ducting.  Anyone have any experience doing this?
TIA,
Bob

Thinking about making a small separator for use on my scroll saw to collect the fines.  Would a 5 gal bucket work with 4" pvc fittings?  Anyone try this yet.  I read somewhere on here the 5 gal worked better for fines but I need to use 4" lines.

How far below the bottom of the cover should the top of the elbo be, or does it matter?  Getting ready to build another Thein seperator and would like to know.