[martin417]

I said this on another thread, but due to the limited surface area available for a vacuum pickup, you probably need higher vacuum than you can get with a shop vac. Look for air ejectors. These devices use the Bernouli principal of air through a venturi to create very high vacuum levels (much higher than a shop vac, but with very little flow) The limitation with these devices will be flow. If you don't get a good seal (read, nearly perfect) you can't develop much vacuum.