Toller wrote:
The current American Woodworker has an article on making clear router
baseplates. And... I found a large sheet of 1/4" clear plastic at a garage
sale yesterday. So I decided to make a base.

The plastic cut, drilled, and routed very easily, with none of the
brittleness I associate with acrylic; so I figured it must be polycarbonate
(which I have not used before).

The article says to use either acrylic or polycarbonate, and to "flame
finish" it.
As soon as I touched it with the flame, it caught on fire! (actually I
tested it on a piece of scrap first, so nothing was lost...)

So what kinda plastic do I have? If acrylic and polycarb can be flame
finished, then I must have something different?

Without knowing more, I can't tell if it's flammable or inflammable
plastic. :-)

Seriously, it's probably acrylic. Flame polishing is a tricky business.
Touching the flame to the plastic will very likely ruin it.Here are
some other ideas for smoothing edges:

http://www.finishing.com/68/50.shtml