On Mon, 22 Nov 2004 23:01:15 -0500, "Linemar2002"
wrote:


Brian Whatcott a écrit dans le message :
...
On Sun, 21 Nov 2004 21:37:04 -0500, "Linemar2002"
wrote:



1) Make a slim box with a heater you can control with e.g a dimmer
switch.
2) Heat a sheet until it is floppy.
3) Drape over a form covered with smooth felt, optionally greased
while it cools.

Repeat steps 2) and 3) once or twice until you get it right.

Brian Whatcott Altus OK

Thanks for the advice! English is not my native language and I am not sure
if I understand correctly: if I make a mold from plaster it would have to be
covered with felt that would have been greased prior to melting the
plexiglass? What kind of grease should I use? I have read somewhere that
bubbles could form in the plexiglass, what would cause this and how do we
avoid this? How thick should the plexiglass be?

Thanks again!

Marcel Trudel
Montreal, Canada


I am concerned not to tell you more than I know. A felt covered form
is a standard recipe among homebuilders who embark on making an
aircraft windshield. They urge the importance of uniform heating, but
not over-heating. Bubbles are not the usual hazard one is warned
against. Cracking and waves are. People use various sizes - 3/16
in, 1/4 in etc ( That's 4.75 mm to 6.5 mm) Your supplier will
probably advise you..... Any grease would be as good as another, I
expect.

Brian W