Need some hold down advice

[Vinny]

I have a number or pieces of plastic that will be front panels. They're various sizes between 3x5 and 8x10 but only 1/4" thick. I need to mill them flat on both sides to about 1/8" or maybe a bit thicker. How do I hold these down? If they were metal I'd just mount a magnetic chuck to the table but they're not. Any ideas?

[dallen]

vacuum, would be the best way in my thinking. probably cheaper and easier to just buy the correct thickness of plastic

[Vinny]

Not an option. It's poured and regardless of thickness the top and bottom need to be cleaned up before a mold can be made of it. The sides need to be squared up too but that's what a vise is for.

[wawoodman]

Can you make them oversized, bolt down, mill, and trim afterwards?

[Vinny]

Thought about that but at least one has to be a tight fit for an existing, and readily available, box. So I'd still have to do it for one since I use the existing box for the original mold.

[Dr Stan]

Why not just use some plexi or similar material?

[TomG]

I've used double sided tape before with good success. Just tape them down to a sub plate and clamp it to the table. Ordinary Scotch brand tape will work fine with all that area.

Tom

[randyc]

Or carpet tape.

[Highpower]

I've got a roll of carpet tape too. It holds a lot stronger than you think it would. I've taped small pieces directly to the top of my vise before with good results. Had a heck of a time getting it loose from the vise again actually without bending it. The part, not the vise...  

[f350ca]

Would crazy glue stick to the plastic? Warm it up and it lets go, maybe too warm for the plastic though.