Reply by Fred Hargis

I think your idea will work fine, just be aware of a few things. A 5 micron filter is not very tight, there will be a substantial amount of fine airborne particles. That may well quickly clog any filter in the return air channel (use a Filtrete ultra-allergen and it will catch it all). Removing the filter from the collector will just make that matter worse. The separator will catch the larger stuff, but the finest particles will journey to the filter media. Maybe you could just vent the collector to the outdoors and not worry about an air return or filters (?).

-- I long for the days when Coke was a cola, and a joint was a bad place to be (Merle Haggard)