Thread: Sheet hold-down
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Unread 12-02-2016, 03:07
AustinSchuh AustinSchuh is offline
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Re: Sheet hold-down

Quote:
Originally Posted by RoboChair View Post
We use small sheet and wood screws straight into the sacrifice, in holes where possible, holding down edges otherwise(takes 4-8 screws to do it this way).
We've been doing similar. Our first op for any new part is to cut a set of screw holes around the part. The second op is to then cut the part, leaving it tabbed into the sheet. The beauty of the screw hole job is that it tells us if we have Z set right to cut all the way through the sheet over the area that our parts are being cut. If the screw holes don't go through, the pockets won't either.

We've been using a waterproof MDF which does not swell. I'd say it is within 0.040 of flat on our machine. We are always looking out for better materials. Do you have a part number/source for the PVC you use at work? Price of aluminum >>> price of endmills > price of MDF, so we should be able to afford a slightly pricier MDF to make life easy.