I have an Avid CNC machine that I'd like to build a vacuum table for. I have a nice used vacuum pump which I can provide specs for if needed. This machine is 96" by 96" and constructed from 8020 aluminum extrusion if you are not familiar with the Avid CNC brand.
This machine is in a production cell running 8 different patterns and the parts are very large. Some of the scrap parts are small and fly away when cutting currently with mechanical clamping instead of vacuum.
I am wondering if there is a standard go-to material for making a vacuum plenum? I'm thinking maybe a 1" thick slab of ABS and then just machine the vacuum plenum in.
What is the gasket material that is used in this kind of setup? Do I size the plenum grid to accommodate a certain size gasket, or do I just choose the groove depth based on maximizing flow and get whatever size gasket I need?
Its common for a vacuum table of any size to be zoned.That way you can apply the clamping force only to the zones that need it.Unless your parts are pretty much identical from sheet to sheet you will pretty much need a spoilboard as you won't want to be cutting a new set of grooves for the gasket for every sheet.I am most familiar with a machine that has the zoned plenum and no gasket on a metal table and the 1/2" mdf spoilboard sits on top of that-no gasket but a very high flow rate for the almost 20Hp vacuum pump and the table has a fair bit less surface area than yours.I know some people who give the edges of their spoilboard a coat of varnish or sealer to reduce leakage.I know of another table that has what appears to be a UHMW polyethylene plenum and four zones on an 8'X4' table and four zones for a 4Kw pump and its sort of adequate.I hope this helps a bit.