Bending Plexiglass

On Mar 25, 2:09*pm, "bumper" wrote:
wrote in message

...
On Mar 25, 5:14 am, wrote:
Old conservative mechanical guy speakin' now. To be safe, I would add
a row of screws or rivets, at least along the sides, to handle most of
the peeling force that will remain after installation. If the plastic
were to be formed, this would not be an issue. Most simple way would
be Pop rivets with holes in plastic slightly bigger than rivet body.
About 4 inch spacing would be fine. If you put one in the center of
the top, forward and aft, this would give you a good way to position
and index the plastic on installation.
Rivets on your canopy frame might be a bit ugly, but not as ugly as
blown off canopy and doing it again.
Good Luck
UH

Another old conservative mech guy:

I would not recommend using pop-rivets of any type on acrylic plastic
(Plexiglas). You may get away with it on polycarbonate (Lexan) or other
mechanically strong plastics, but it may crack Plexi.

Even if you over-drill the holes to help prevent cracking, the pop-rivet
itself is set by drawing in a metal bead at the end of the mandrel to expand
the rivet. This will apply pressure to the Plexi and may well cause stress
cracking. Note that you might get away with it if the "factory head" (the
original rivet head) is on the Plexi side and the "shop head" (the part that
expands) is on the poly side - - still, I wouldn't risk it. Safer to drill
(using plastic drill bits or drill bits ground to reduce relief angle -
again, to help prevent cracking the plastic) and then tap the plastic for
small machine screws (just like Mecaplex does).

bumper
maker of the world famous QV and MKIII
zz
Minden, NV

bumper

I agree. I was assuming he would be using polycarbonate and did
suggest oversize holes.
UH