2 Attachment(s)
holes in vac table plenum
I laid out a grid of 17/ 64 holes on 5-1/2 centers through the “high spots” in the vacuum plenum. The hole goes all the way through Trupan top and out of the bottom of the 3/4” plywood base.
At the bottom of the hole is a 1/4 inch threaded T- nut which can be used to secure the hold down clamps.
Sometimes I will use a lag screw coming up from the bottom to hold the work-piece using “pull down.” ... you have to miss the lag screws however...
Works great, I cover the bottom holes with heavy tape when not in use, vacuum still works fine.