How to hold perspex flat

[ngwagwa]

Hi,

I am trying to engrave an A4 sheet of 2mm thick perspex with a 0.02mm depth of cut and then cut out the parts and my problem is getting the damn thing flat. I have secured a sacrificial piece of 12mm perspex to the table and skimmed it and have then secured the 2mm sheet to it with double sided tape. The problem is the tool is the correct depth at the start of the cut but there are areas where the tool is shy of the workpiece, where the cutter misses the perspex is different for every workpiece so I am assuming that the double sided tape is to blame (I cover 95% of the workpiece with the tape). I am wanting to engrave 12 of these onto the A4 sheet.



Superglue sprang to mind but thinking abuut getting the sheet off after engraving would be a ball ache - I suppose I could leave the protective backing on the perspex on the table but that would mean re-skimming the sacrificial mounting piece each time and I have about 6 A4 shees to cut.

Any ideas anyone?