I've been using hold down clamps up to this point in time. I'd like to convert to a vac hold down system but not sure what it encompasses. I'm looking for information on how to set one up and what equipment I would need to purchase. Any help would be greatly appreciated.
Regenerative vac or a shopvac type vacuum system will work for plywood and some wood parts but the vacuum hold down is a log function of the area. The bigger the area, the stronger the hold down. try Lighthouse, BradyvAc or Black box vacuums. A search on Ebay will find regenerative pumps that can provide lots of vacuum power. When I am cutting ply I use a regenerative pump which works fine for most parts. Some care may be needed as to where the cut starts and which bits are cut first, etc.
For smaller items, I use hard vacuum with a gasketed fixture to hold the piece. For example, I have a 2 inch thick p[iece of walnut that is machined with a 1/2 inch ball mill inside and out to a depth of 1.875. The walnut is 4.5 by 5.25 inches. I use a bit of uhmw with a venturi pump to hold it down. I screw the uhmw right to the table.