I put a leading edge landing light in a C140 and drape formed the lens like that. On the Sikorsky X2, we had a felt covered mold. Sheet hanging vertically in the oven, pulled it out with a bunch of hands and stretched it over the mold.
Are you looking for the elastomeric bushings? I just got some SuperPro SPF2092BK Univeral Link Pin Bushings today in what looked like resealable packaging for beef jerky. Bryan Cotton reports good service with them. They are harder/stiffer than the original rubber, which seems to extrude and sag over time, and in my case, over the 20 years of this build, had âsmog checkedâ. Made in Australia, they are widely available online.
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Yes, Iâm looking for the rubber bushings. I designed a 3d printed mold over the weekend but I havenât had a chance to make a bushing with it yet.
Still true. @NWade uses them too.
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Not canopies, but a related topic. Wind screens. I performed a series of experiments related to Lexan and fuel exposure. Fuel will cause Lexan to craze only if the Lexan is under stress. You can soak un-stressed Lexan in car gas, and it wonât craze.
So, if you guys get in to forming plastic, how about drape forming us some windscreens.
Wes
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Stress definitely plays a factor in the damage to Polycarbonate and acrylic. Iâm also thinking that auto fuel can be MUCH worse than 100LL. Iâve seen first hand how the difference in additives from one brand to another can destroy plastic fuel line components in just a single tankful on a car. I still canât believe they went to that through-the-windscreen fueling for the B models. That was the worst feature ever on the Onex.
Rusty
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Yea, I noticed crazing on my Onex windscreen, and I have never allowed fuel to contact it. However, I can see vapor pouring out of the tank every time I remove the cap.
I would say it plays the major factor. I took my cutout scrap from making the fuel fill hole in the Onex windscreen and âDrap Formedâ it over a coke can in the kitchen oven. I soaked it in car gas and 100LL with no effect. I stressed a piece of polycarbonate from Home Depot and soaked it in car gas. It crazed almost immediately. I soaked a small piece of Home Depo âstuffâ, unstressed, and no effect.
After soaking, I pinched the stressed piece between my fingers and it snapped, as expected. I pinched the unstressed piece between my fingers, and it just folded like an unexposed piece would do.
Wes
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Another take on forming acrylics. Bad Chad uses a gas BBQ drill with a home made heat distributor, puts Parchment Paper on his mold, and uses spring clamps. http://www.youtube.com/watch?v=FuG4RDbvyhU
Me, Iâd add a fan to stir up the heat, and a thermometer.
Just ditch the silly centre fueling point, in front of the polycarbonate windscreen.
My Sonex has wet wings, which feed the central âheaderâ tank (no fuselage fueling point) 