Top Hat Baffle Design - Outlet Length and Angle

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Forum topic by kocgolf posted 01-26-2017 06:47 PM 442 views 0 times favorited 5 replies Add to Favorites Watch
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350 posts in 2326 days

01-26-2017 06:47 PM

I haven’t been able to find information on this with searches, so here it goes. I am planning to build a top hat Thein baffle, and the two places in the shop that I may be able to permanently locate my DC have unique vertical space issues. Is there a draw back to have a long (say 4 to 6 foot) vertical outlet duct as opposed to the more stand flexible foot or so? I have room for the hat and can under the end of a bench, but really don’t want to loose the entire benchtop surface to the motor and filter, so I was going to mount all of that a good 4-6 feet in the air. I have 12 foot ceilings.

I know I would need a hole in the bench with the duct coming out, but it would still give me space to put a tool or two there. Also, I suppose that dead center and dead vertical is preferred, but how much would it effect performance to have the outlet duct make an immediate 45 degree turn and then exit the benchtop at the corner of walls? The actual duct inserted into the top hat would of course remain vertical.

5 replies so far

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667 posts in 1901 days

#1 posted 01-26-2017 07:45 PM

My motor and filter sits about 3’ above my thein baffle and is connected with a piece of PVC and a piece of flex hose. I haven’t noticed any issues from this arrangement.

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1960 posts in 2177 days

#2 posted 01-27-2017 02:49 AM

Your vertical duct has not bearing on efficiency of the top hat itself other than the “too long of a run” issue when combined with the rest of your ducting.
Same “theory” goes for your immediate turn: all depends on how drastic of a elbow will be there (from the looks of your drawing, that is a serious turn).
Why not put the barrel and top hat ontop of the bench top, leaving the underneath for some kind of storage. Or wall mount/shelf up higher for the barrel as high as it goes.

-- The Carpenter Bee is derived from the Ancient Greek word wood-cutter

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350 posts in 2326 days

#3 posted 01-27-2017 04:29 AM

I’ve definitely considered going high with the entire unit, including barrel, in a different location. I’m just not sure how to empty a barrel of sawdust sitting suspended 4 or 5 feet up in the air. I would really like to try and save the majority of that benchtop space and not have anything sitting on top of it. I would sacrifice a “hard turn” on the ductwork over losing the whole counter surface space.

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117 posts in 1839 days

#4 posted 01-27-2017 06:01 AM

kocgolf – If you can mock it up before committing the final arrangement try it out to see if it works. The only drawback I see is ability to empty the barrel.

I want to move my dust collector sit directly above the separator and turned 90 deg (inlet in the vertical axis) to have the collector inlet inline with the outlet of the separator and then duct the exhaust to the outside. The problem is emptying the barrel when full. Can’t pick up the DC & Separator without three people to lift and separate.

I wonder if some sort of skirt could be fashioned to allow the chips to fall into the barrel and allow the barrel to be slide out from under the separator. The skirt could fashioned out of a thin neoprene strip or similar material. That would certainly free up some floor space for more tools! Hmmm… maybe a future shop experience.

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350 posts in 2326 days

#5 posted 01-27-2017 03:30 PM

I have thrown around similar ideas. Even putting the entire thing in straight vertical alignment but hoisted up so the bottom of the barrell is about 5 feet high. I was thinking of using a “trap door” method to empty, but that would require a bag setup like I’m trying to get rid of! I fear that if there was just another barrel underneath to “catch” the drop it would just make a huge mess and put all kinds of dust back into circulation. I think I will probably stick with this under the bench plan and just skip any kind of extreme “turn” from the output.

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