Vacuum Clamping

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So, I’ve heard of, and read about, vacuum clamping, so I figured I’d give it a try. I’m working on a router jig for the second cross design and really don’t want to make clamps, or buy a pattern bit with the ball bearing below the cutter instead of above. With that, I took a piece of MDF, small rectangle, and drilled a hole for a male quick release air fitting, then a smaller hole all the way through. Teflon tape on the fitting, spin it in the hole, chuck it to my Harbor Freight AC vacuum pump turn it on and slap it on top of the router table. Even without a gasket, I could tell there was some vacuum.

Next, I took an oil filter o-ring, from the wife’s Saturn wagon filter (No, not the one on the car, this one is extra) and placed it between my MDF pattern and the router table top. STUCK! With that success, I stuck a piece of 3/4 oak ply to the MDF pattern and tried it on the router table, with a 1/2" diameter pattern bit. Not too bad. I think that the oak ply allows enough leakage that it slipped a bit.

Dug through the stuff drawer and found some foam tape gonna try this out. Anybody else tried vacuum clamping?

Keith "Shin" Schindler

Worked up a vacuum router jig for the second cross that I’m working on. Made the jig from MDF and with a little bit of closed foam weather stripping it holds the piece great. I tried to upload some photos, but “No Joy.” Will try again, later.

Keith "Shin" Schindler

This is the jig, with temporary weather strip tape, just to test the concept.

Jig with a cut piece in place.

Cut piece, jig and vacuum pump.

Close up of the tag on the Harbor Freight vacuum pump.

I bought a new roll of weather strip tape and redid the jig. It holds better, with a greater vacuum “footprint.” I really need to upgrade my pattern bit, though. The two-cutter, straight edge bit, works okay on pine, but I want to do Oak, Walnut and other hardwoods.

Keith "Shin" Schindler