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View Full Version : Simple Vacuum Hold Down



rcnewcomb
03-16-2006, 10:45 AM
It has been working for us, it might work for you.

On our last sacrifice board we had cut grooves for a 2x4 area for holding sheet material. Typically we don't cut anything larger than 2x4. It worked quite well but the problem was that frequently we were cutting boards smaller than 2x4. We do glue-ups of exotic woods and cut boxes out of them. The glue-ups aren't always 2x4.

We have also been using the vacuum pods for pieces under 12"x30".

When we replaced the sacrifice board on our table we decided to try an experiment. We cut the hole for the shop vac, but then, rather than cutting the channels first, we tried just placing the gasket material directly on the table. For our materials it has worked very well. When we need a different size vacuum area we just cut out sections or scrape off the gasket material that we don't need and lay down a fresh strip for our new border.

Additionally, we have been making some plenums that just sit on top of the vacuum area. They are made from 3/4" veneered MDF plywood. The underside is hogged out to about 1/2" deep. We now know to leave sections in the hogged out area so the middle of the board doesn't sag under vacuum. These plenums have the gasket material placed so that when we cut boxes out of the glue-ups the pieces stay in place.


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