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Vacuum Jigs:

One approach is to use a jig, either with or without gasketing, to make sure all of your vacuum is reaching exactly where you need it and not anywhere else. For example, if you needed to cut a wheel for a toy, this part would be very small compared to a full sheet of cabinet parts. One option would be to create a jig to fit over the hole in your table which is connected a single Fein Turbo III vacuum. This jig could be made from just about any non-porous material like plexiglass, wood etc. Cut the jig larger than the part and place the jig on the machine bed. Next run your tool path around the jig just kissing the surface to mark where the part will be cut. Then use gasketing material around the kiss cuts and finally cut a hole into the part of the jig that will fit over the vacuum hose hole but inside of the outer most gasket ring. This will concentrate every bit of the vacuums holding power on your small part. Gasketing is king in the world of using every bit of vacuum you have.

Below is pictured a jig created to hold a plywood blank that will be cut into a circle with a round hole in the middle. The gasketing in the center keeps the vacuum from being lost when the center hole is cut. The gasketing around the outside is just inside of the cutting so vacuum will not be lost. The extra strips of gasketing is just to keep the vacuum for deforming the part since you will get a lot of pressure pushing the part down. Also notice the rectangles cut that allow the vacuum to reach the bed of the machine as well as allowing the vacuum from the hole in the table to reach the part.

When cutting thick solid wood 4/4 and 8/4 tropical woods and some American you need a strong vac setup. 3/4" acrylic with a simple hole drilled about 1/2 way through the edge and a small hole then some 1/8 vac foam tape and some thin neoprene rubber to help keep parts from jiggling around. This is screwed down to a sheet of ¾” ply that is held with a ShopVac setup. This version is 4 for 5" to 7” long wood, the next up to 15”, then to 24” then to 36”.

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