solarwingpm

I have a Cumic sailplane (Airtronics) which I just gave to a friend. I have not flown it for several years and the wing tip joiners for the leading edges are missing. They have female copper tubes for the leading edges with dowl for the traiing edge joiners. For the leading edges I'm thinking steal joiners. Does anyone know/ recall?? Thanks.

isoar

My Feedback: (1)

The joiner at the spar (thick point of the wing) carries the load. I think the LE were wood dowls also. LE and TD pins are just for alignment.

solarwingpm

Ok, steal probably would place a little too much weight out from center. I was actually thinking about the spar jointers as you mentioned. If you find out for sure let me know. Still somewhat worried that dowel may not carry the load for the spar on a forcefull lunch. Thanks.

John C

Hi, Phil.

PM Sent. I'd get some CF tubing and make up joiner rods with this.

John C

BMatthews

By "leading edge joiner" are you talking about the bigger tube that is located where the airfoil is the maximum thickness? If so those main JOINERS back at that time were typically spring steel rods. Likely around 1/4 inch in diameter. You'd have to measure the inside diameter of the receiving tubes in the wing parts to size them. If the tubes are significantly bigger in diameter then the kit may have used an early carbon tube or rod or even just a fiberglass tube or rod.

These days thick wall carbon tubing or solid carbon rod would be a more than able substitute for either the smaller steel rod or a bigger fiberglass tube joiner.

solarwingpm

Yes, I'm refering to the main wing tip joiners(in spar at leading edge). Your right about spring wire being used. Found a post where the seller descibed them as "spring wire at 7/32" inch diamteter" which is the diameter of the copper tubing in the ends. That's what I'll use since I have some handy. Thanks.

Phil M.