On Sat, 15 Jan 2005, Computer Collector Newsletter wrote:
  I've heard some horror stories about whole
(expensive!) sheets of plexiglass
 simply breaking in half when incorrectly drilled through.  The guy at the
 plastic supply company tried selling me a special drill bit, but I'm hesitant
 about that.  Does anyone has hands-on experience and tips (vs. just
 speculation) about working with this stuff?  This computer will be on display
 as some public events, so the final appearance is very important. 
Plexi is a pain in the ass.
Drill VERY SLOWLY. Low speed and no pressure. A small stream of water
helps; it cools the cutting edge.
De-stress the holes afterwards with a bevel and sandpaper on
a nail.
There's better plastics to sue. If it's just a flat sheet, I find
lexan types much more forgiving. It's hard to bend though.
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