so, I picked up a small bead blast cabinet (made of wood, lined with rubber) - it's about 2 feet by three feet - the hole to which one applies vacuum is small - 1 inch in diameter - to test the unit, I just duck taped my shop vac's hose near the hole - didn't try and seal it well or anything - then I bead blasted some brake calipers - worked great, the air inside stayed clear, etc - so the 1 inch hole is adequate with my shop vac sucking on it. After a bit of flailing around in the internet, I found equations for the flow through a sharp orofice, which suggests that if my shop vac pulls 5 inches of mercury (about 2.5 psi), then i would be seeing between
350 and 530 CFM of air flow - of course my shop vac has no specs (dirt devil wet/dry) so there is no easy way to see if that is reasonable.I'm trying to avoid running a really really loud shop vac when I'm using the bead blaster, hence my search for info - I can't find anything on the scalability of a cyclone type separator - anyone know if I can make a small one with a 1 inch entry hose using a 1 or two gallon can or do these things not scale down well? Any ideas whether a 1/3 HP heater blower will do the trick for evacuating the dust? Since the unit is outside, all I need to do is blow the dust into my garden, I think, though providing a collection bag might improve the aesthetics - a smaller blower, like found in shower ventilators might work, I suppose I could just experiment, but sometimes using collective knowlege is a good idea....
seeking thoughts - anyone?