Posted: 8/22/2009 20:33:29
Can anyone point me to sources for how to form a windshield
with no compound curves? The existing windshields were installed in 1988,
and are crazed and cracked. What thickness plexiglas should I use?
Does it need to be heated and formed around a mold? I've watched the EAA
video on drilling holes so I just need to get to that step! Thanks, Mark
Posted: 8/27/2009 19:06:50
I made flat wrap windshields for my Acro Sport II and they came out really good. I wrote an article on how to make them and it appears in Acro Sport Newsletter no. 62. The Newsletters can be viewed at <TheBiplaneForum.com>
Posted: 8/27/2009 19:15:15
Go to Sport Pilot magazine archives. There are many articles about working with plexiglass.
Posted: 8/28/2009 19:19:48
Since you have the old windshield(s) to use as a pattern, it should be really simple to duplicate them. Use the same thickness Acrylic. Cover the old shields with good quality felt from the local fabric store. Take them down to the local plastics fabrication shop and let them flat-wrap new pieces for you. Trust me - it's a lot cheaper than trying to build your own oven for a one-shot job.
Otherwise, contact your local EAA chapter and find someone who has already built an oven. I'll bet they would be more than happy to help you drape a new unit. There are common mistakes to avoid such as letting the Acrylic absorb moisture which then bubbles under heat. It has to be dried out before heating to molding temperature.
Best of luck!
Posted: 8/29/2009 08:25:25
Neil, thanks - good article. Now I just need to find a large oven...
Posted: 8/29/2009 20:35:27
The more I look at this the more I think I should just have them made professionally. I'll check around for shops in my area who can form them. There are cracks in the old ones that deform them so I don't think they'll work well as a mold. Thanks!
Posted: 9/1/2009 06:26:15
If you do end up deciding to form your own and need to build an oven, there's an excellent reference on oven building which comes from the special effects industry and their need for similar temperatures and techniques for latex masks. The book is "Foam Latex Ovens" by Gary Boham. I found it at http://www.fxwarehouse.info I have one felt covered aluminum / wood mold just about read to go for 1/2 of a Russian aircraft's windscreen. Hopefully, I'll be taking on the oven building this winter. (Near Denver, CO) Best of luck to you either way.
Posted: 9/1/2009 21:28:27
I'm going to have them made by Dave Germann at Plane Canopies in MI. He'll end up with a mold so if anyone else needs a windscreen for an open cockpit Chipmunk, that'll be the place to go. Though it would be fun to make them myself, I have control surfaces to recover this winter and lots of other work. Your Russian project sounds interesting - best of luck to you too! Thanks again for the help. Regards, Mark
Posted: 9/2/2009 08:57:32
I had the pleasure of seeing you bird at SGJ just before you picked it up a few weeks ago. Nice bird. If you need help with the fabric I am doing a couple of aircraft here in the Jacksonville, FL area but would be happy to coach you (advise is free :-)) ) or do them for you.... cheap but not free... Email me at firstname.lastname@example.org or call at 904 262 0039 or C 904 403-3360. Terk
Posted: 9/4/2009 13:54:25
Thanks for the offer! I’ll hang onto your contact info. My plan is to recover this winter, then
repaint. Plan to do it myself, and it
will be new experience (except for fabric covered scale models in the distant
past…). Thanks again. Regards, Mark