Cabane Strut Fittings

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danoliver
Posts: 89
Joined: Sat Feb 25, 2017 7:58 am
Location: Cincinnati

Cabane Strut Fittings

Post by danoliver »

In every picture I’ve seen on line of cabane strut fittings they are made of two overlapping bent brackets tacked together (Like the red construction paper cut-outs in this photograph).
Am I a fool for making mine of three welded pieces per my interpretation of Vi Kapler’s ‘75 drawing?
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Bill Church
Posts: 7
Joined: Fri Feb 24, 2017 8:48 am

Re: Cabane Strut Fittings

Post by Bill Church »

Dan,
No, you're not a fool.
The detail for the fittings shown in Vi Kapler's drawing are the same as shown in the original plans, and are equally as strong as the versions made with two U-brackets ***provided the welds are done properly***.
Many builders opt for the two U-bracket method as a "belt and suspenders" approach, that provides some insurance in the event of a defective or insufficient weld. However, there are several other welded connections in the plane that will be exposed to far greater stresses, that would result in catastrophic failure, should they fail in flight - so the integrity and quality of all welds is a very important factor to keep in mind at all times.

Bill C
danoliver
Posts: 89
Joined: Sat Feb 25, 2017 7:58 am
Location: Cincinnati

Re: Cabane Strut Fittings

Post by danoliver »

Thanks for your response Bill. You gave me the confidence to go ahead with the welded three piece fittings and the caution to re-examine my technique. I did a lot of re-reading of books and discussions and re-watching of videos. I also did a good deal of experimenting. One thing I noticed is that the welds don't usually break, the steel right at the edge of the weld breaks. When it comes to oxy-acetylene welding 4130, I don't think it's enough to just pay your torch over the the finished weld as many advice. I found it's better to reheat the weld, and more importantly, to reheat the area adjacent to the weld all to an even red.
Anyway the fittings turned out nice and they seem plenty strong.
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