I have been searching the net for polypropylene and i cant find any suppliers selling the thin stuff. all i could find was 1 inch thick stuff and it was expensive.

Also what thickness do i need for a 50 to 68 inch rotor?

Grant,
I have been looking for some in the .032 to .050 range but haven't got any as yet,, WE will keep looking.. I would think that some could be found around the bigger cities..
Good luck,
Jim

Isn't it the same material, which is used in fuel cans and candy boxes? I use the plastic, which the fuel cans are made of. Don't worry, the can was empty before cutting the hole It has worked well for my autogyro for tens of flights. I also used the candy box plastic first but it was too hard plastic. It broke off in a hard dead stick landing.

Grant, Jim and any body else...

If you will send me your surface mail address(s) I'll be glad to send you some sheets. I purchased a big roll of .032 poly propylene a while ago and it will last me about 6 lifetimes!

Bill

Humm, What have you guys been using for hinges if you cant find the polypropylene?

Fuel can like a red plastic gas can?

It seems that bilf is going to send you some polypropylene. I still answer to your question. I meant a fuel can like the white one on this picture. It is maybe a bit too stiff for small hubs. I don't know how it works in winter times in -20C. I'll send you a report if the plastic will fail in cold weather.

SO your talking about glow fuel jugs? i Have plenty of them but i tryed using it and it streched bad when i applied light pressue against the badle stop and proved to be too weak. flexable yes but very strechable. My blades also dropped all the way down i had 10 degrees down flex limti and that stuck there until it was spun up. How much down flex limit shoud there be?

I quit using polypropylene long time ago. I have been using fiberglass head which is much easy to build and more robust. My ACDC (.050" thick) and Minnie (.030") both uses fiberglass head. I bought the material from ACP Composites.

http://www.acp-composites.com/acp-fs.htm

http://www.deltronix.net/cgi/acp_display.exe

Wahid

Wahid,

Thanks for the link. I tryed using gutter pipe scrap for a hinge today ona 48 inch rotor and it didnt fly[:@] The plane had a 44x13 wing on it so i thought it would stablize it but it didnt. It did takeoff but kept rolling hard into the ascending blade. Thats weird because it shoud roll into the decending blade. My wing has 3 inh alierons with barn door throws and it just wouldnt over come the right tilting even with full rudder assistance.

Blades can flap 45 degrees up and about the same down. When the plane is standing still the blades droop a good 30 degrees. once spinning they form a nice coning angle. the pvc is very flexable and tough but it just want work for some reason.

Now are hinges suppose to be somewhat stiff or floppy? The pics i see look like the rotors are not drooping much at all when the planes are standing still.