I have used double sided tape to hold perspex and it does work BUT make sure you get the removeable stuff otherwise you will have trouble getting the stuff off the workpiece, you will probably have the same problem with spray adhesive. I would suggest something more rigid than corrugated cardboard as a backing like a piece of plywood (the double sided tape doesn't stick too well on MDF in my experience). If it helps this is what I have been using https://www.ebay.co.uk/itm/25mm-50mm...SFhw74yqXqKGfg
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