Slightly OT: tips for fabricating with plexiglass?

Computer Collector Newsletter wrote: I've never seen Plexiglas shatter or split, but small cracks in the corner of a cut or radiating from a drilled hole is very very common. Plexiglas is a nightmare to machine. That includes drilling, cutting to size, sanding, everything. It's very subject to stress fractures, which means you have to cool your cut and cut very slowly and evenly. Unless you're very good with a hand drill or have a drill press, I would recommend Lexan instead. If you do use Plexiglas, there are some things you need to do: Have some spare drill bits, saw blades, etc. You'll probably dull some, and cutting with a dulled bit is very likely to cause cracks. Cool the cut with water or a light soap solution. This reduces stress during the cut, and also carries away the fragments as you cut. Polish all cuts and radius all edges. By "polish", I don't mean "make it shiny again", but remove any tool marks and ridges, and sand the corner off the edges. Any sharp corner, inside or outside, is a "stress relief point". Sounds like a good thing, right? but stress is relieved by cracking at that point. If you're bolting this piece together, or to another assembly, use some kind of rubber/plastic grommet at attachment points. Even with a good cut and good finishing, the stress of tightening screws against the Plexiglas is still risky. Even a stiff "nylock" washer is better than nothing. I'd use Lexan if at all possible, or just build a metal or plastic case with viewing windows. If you do that, you can use clips or adhesive to hold the Plexiglas and not worry about drilling at all. Doc