Additional questions asked elsewhere

[phil (admin)]

Q: I read about the idea of expanding your design to 4" hose sizes, implying use with a fullsize dust collector.  I read about the problems you were trying to solve - but all of these were manifested with shop vac -2.5" size implementations. I do not think the carrryover problem you solved exists with larger scale dust collector solutions.  The traditional trashcan solution for a fullsize dust collector uses 4" hoses and a 30 gallon trash can, which is considerably taller than the 10 gallon can you used.  I have used a 30 gallon trashcan with a homemade lid and a 2 hp Jet dust collector for years. I never experienced the carryover problem you mentioned.  My lid looked just like yours, except it has no baffle.  I suspect it works as well as it does because its so much deeper and a larger diameter.

A:  Thanks Bob.  Interesting observations.  I have personally witnessed horrific scrubbing in shops I've visited, even with the 30-gallon cans.  Many people I know only use the cans with their planers because they can't keep anything smaller than very large chips in their cans.  But I will do testing w/ and w/o the baffle when I finish building my larger model.

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Q:  That looks great for a shopvac to keep the drum from filling up as fast. That sort of design typically doesn't scale well to larger collectors if the goal is to separate out the fine dust. Once you start moving more air the physical size required makes this design impractical. This is the reason for the popularity of the cyclone--done right it can separate out a large percentage of even the very fine particles.

A:  My tests indicate that my design scales infinitely better than designs w/ no baffle. I'm trying to apply the 90-10 rule. That is, I'm trying to provide 90% of the performance of a true cyclone for 10% (actually, a lot less) of the cost and complexity (and size). I make no claims of outperforming or even being the equal of a large Torit cyclone.