I have been using a modified shop-vac for several years as a 'Bee-vac' quite sucessfully.
 
 The one I have is an inexpensive one with the inlet hose attached to the top cover, pointing straight down into the canister with no obstructions.  Modification consisted of discarding the small hose that came with the machine and replacing it  with as large a hose as would fit on the inlet to the machine.  (2 1/4" I.D. I think.)  This new hose was chosen for large size and the smoothness of the inside surface.  I then placed two (2) filter papers in place of the single one usually used.  The idea is to have a large volume, low velosity flow of air.
 
 The shop-vac (small, cheap, plastic) was about $20.00, and the hose another $15.00.
Dennis Morefield
Sideline Beekeeper, Oregon, USA
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