I have Goldberg Ultimate. One of the front aluminum cabane struts has broken where it fastens at the wing and the fuse.

Would anyone know of a better material to use that would be more durable than the aluminum?
Also, any suggestions of replacing these struts without damaging the fuse very much would help.

Greg

bipeflyr:

Get a real "Tin" can, the tin plated steel kind, cut doubler plates to span the break. Secure them with small screw and nuts, with a thin layer of epoxy between the doublers and the original aluminum.

Getting the broken strut out is more bother. Wrap tinfoil around the wooden part of the plane to keep from burning it, use a torch to heat the strut (this softens the epoxy) and pull it out. It's a pain, reinforcement is much easier.

Bill.

Per your description, it sounds like the strut is broken in two or more places. Is this correct? I would attempt to patch the strut with aluminum pieces and small screws. If you have room at the particular crack, use a patch piece on both sides (double splice). If the strut is really messed up, I'd replace the entire unit with a new one. I can't really think of a practical way of avoiding cutting wood. Just enlarge the cut-outs on the turtle deck until the strut passes. Patch the turtle deck after the new strut is in place.

As far as material goes, it's either thicker aluminum, or steel. I would try thicker aluminum first. If you're really eager, you could try to mold a fiberglass or carbon strut.

BTW, how many hours do you have on this bird? Do I have a strut failure to look forward to in the future?

I am currently building the CG Ultimate and at the same time I scaled the design up 15% larger to get an Ultimate that has a 62 inch wing span.

For the larger Ultimate I contacted TNT the landing gear people and they bent up a set per my drawing. Its made of landing gear aluminum which is a lot stronger than the flat stock hardware store aluminum.

TNT will work with you if your interested and provide what you need.

tonyc

Thanks for all the good idea's. If I had known this could be a weak spot on this plane I would have rather had TNT bend up a set for me, sounds like the best idea yet.

The cabane is broken at both ends, at the mounting bolt inside the fuse and at the top where it is bent flat to fasten to the wing.

The plane has about 3 hours flying time on it with an FX 91 without an isolated mount. Also the plane had one crash. It stalled and went nose in from about 5 feet up. This didnt seem to hurt the front cabanes but did bend one of the rear ones and was bent back into place. Maybe the front ones did get hurt in the crash.

Im still not sure if I'll replace just the one damaged front with some better aluminum or have some better ones made up and replace the whole bit, I'll hold out for more reply's and think about what I'm gonna do for the time being.

Thanks for your advise.

Success...
I was able to get the same material from the LHS and make a new strut that went from the bolt in the fuse at the right front, up to the wing and down the other side of the "A" shape to the top bolt of the left front cabane. The new piece bolts in 3 locations and I was able to slip it into place inside the fuse without any cutting of the deck.

Thanks again

bipeflyr:

I'm happy for you.

Enjoy.

Bill.