Lexan vs Acrylic/Plexiglass - help

[jiott]

For a windshield the thickness is more important for strength than for bending. To be able to resist say 140 mph Vne a minimum thickness (probably different for Lexan vs. acrylic) is critical to avoid flexing inward in the slipstream.

[Osprey220]

Plane I'm working with is a 582 model II that cruises at ~65 and Vne is 100 or 95. The 1/16 is supposed to be sufficient for this plane.

Supposedly the 1/8th or .93 is needed for the later models with 912's.

[avidflyer]

I've always run .060" lexan on my Avid MK IV with a Jabiru engine. At 100 MPH, you would see the windshield start to buckle into the v tubes just behind it. Didn't seem to hurt anything, but I stayed below that speed. Not hard to do, cause that was right at max speed anyway. Lexan does scratch fairly easy, but when it's time to change it out, clamp the old windshield to a new piece of lexan, drill out all the holes, cut it to the same shape as the old one, bevel the edges where you cut it, and reinstall. 2-4 hrs later, you are good to go. JImChuk

[HighWing]

Agree with Jim. My first IV - 1993 came with .060. The new was "upgraded" to .093 and has lots of craze lines at the wing root. Soon, I will go back to the .060. I guess we have a tendency to "upgrade" over time, but I don't remember of a case of the thinner windshield doing anything more than the oil canning described, but I do remember reports of the thicker windshields cracking top to bottom at the wing root max bend area on at least a couple of occasions - one a close friend on a cross country. His emergency solution drill and stitch using safety wire. As far as caving at 140 mph. Not an issue as it far exceeds max speeds on a IV. This is one of the reasons I wish the IV was still available. The vast majority of current builds are 7s and there are a bunch of differences and many decisions we IV and earlier builders are contemplating are unique to those models. And, truth be told, I am still heavily influenced by an old flying buddy who built several IVs - the lightest weighing 604 lbs empty. It was a screamer as far as off airport flying was concerned. .060 Lexan weighs pounds lighter than the heat formed plexiglass.

[efwd]

not to mention a SS7 acrylic will be a nightmare to replace if its source goes defunct. Wish I had that IV windshield if that's all that there is to it to make a new one.
Eddie

[jiott]

That's why we need to support our Kitfox factory and buy as much stuff from them as possible. If their acrylic windshield source ever goes defunct, they will immediately bring a new source on stream.

[Av8r3400]

That's why we need to support our Kitfox factory and buy as much stuff from them as possible. If their acrylic windshield source ever goes defunct, they will immediately bring a new source on stream.

Kitfox's molded acrylic source is LP Aeroplastics, a relative giant in the global aircraft parts chain. They are not going nowhere.

[Osprey220]

Plane I'm working with is a 582 model II that cruises at ~65 and Vne is 100 or 95. The 1/16 is supposed to be sufficient for this plane.

Supposedly the 1/8th or .93 is needed for the later models with 912's.

Sorry - meant 0.093

Owen

[blbills]

Does anyone have a good source for Lexan? All the online shops I've googled charge an arm and a leg for shipping. Just want to make some new doors with .060.

Thanks!

[FoxbuilderWill]

Regional Supply in Salt Lake stocks it. Haven't called about price yet

https://www.regionalsupply.com/itemd...200.060PM48X96