Thinning plastic card?

[Chuckt5]

I have a bit of an odd question, but does anyone know of a good technique to evenly thin plastic sheet? I need to thin some coloured  .01" card down to .005" (or thinner) but I need to keep it as even as possible.

I know you can get white card in .005", but I also need black, red and yellow in .005". The thinnest coloured card evergreen offers in styrene is .01". My current plan is to face sand it on a flat surface with some sand paper taped down face up, but is there a better way to do this?

Thanks in advance, Chuck.

[coyotemagic]

That's how I would do it, Chuck.  In fact, I've got a 12"x12"x3/4" piece of smooth granite for sanding flat surfaces.  I just tape a piece of sand paper to it, grit up, and sand away.  But why not just paint .005" sheet?
Cheers,
Bud