I do quite a bit of 3D carving, and I don't use glue or tape or a vacuum. Sometimes old school is best. I know that the prevailing wisdom is not to use fasteners where a spinning bit can contact it, but, if you know where your tool path is and do a preview, seems like an over reaction.
The solution I use is to modify the spill board with a grid of 1/4" x 20 tee nuts as shown in this photo of my Shopbot desktop. Since I always use a 2" offset, two of the clamps are always out of the way. It's very versatile and only limited by your imagination. You can make different length arms and different length screws for different thickness stock. Certainly cheaper than a vacuum pump and very quiet.
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Last edited by Pete Taran; 11-12-2019 at 3:53 PM.