tubing wall for kitfox 3 1050

[TJay 1041]

thinking about making new wing struts for my kitfox 1 does anybody know the tubing size and wall thickness for the kitfox 3 1050 also does anybody know a good place to buy weld in rod ends for the ends.

[EDMO 1078]

TJay,

The easiest thing for you to do, is to cut your struts about 6 inches from the fuselage fitting, or from the cross tube on the wing end, and splice a larger tube onto it using the methods shown in AC43-13. I can post it if you cant find it on the FAA site.

Kitfox uses .o49 wall 1" diameter tubes for the later models. Leni and I used .058 wall tubing for scratch-builts.

The later Kitfox strut fittings were about 10" farther out on the spar than the Kitfox 1, so that may have been a reason they went to larger struts.

I am sure if you use 7/8 tube it would be plenty strong, if you don't have it now.

I think the original Kitfox 1 struts were 3/4" .035 wall, so a 7/8" .049 or .058 wall should fit over them nicely.

I found cheap rod ends on ebay for mine, but they were larger than the originals, and I had to make new spar fittings to fit them.

The rod ends are possibly the weakest part of the strut system, and take the same 1/4" bolts, so you may be better off with what you have. I am making mine because my length and angle of fuselage fittings are different.

EdMO

Edited 2 Sep 2015 by Ed In Missouri

[TJay 1041]

Wonder how much strength you would gain if you was to take a 7/8 tube .049 and rip it in half some how and weld it on the front side of each tube then glue the wood on the back of the tubing and fill the  top and bottom gab with epoxy to make it flush. Just thinking out loud here. That would be the quickest way to add strength I guess.

[EDMO 1078]

How much are you going to warp your struts with full-length welding? I would rather just weld each end of a tube at a 30 degree angle.

I guess you could cut your struts and slide a tube inside and reweld your struts - I don't know how the strength would compare to a larger tube on the outside, but at least it should add something. I think it would be just as easy to put a tube over the outside and weld both ends, keeping your original strut length.

EdMO

Edited 2 Sep 2015 by Ed In Missouri

[Dusty 126]

If you are going to replace your rod ends consider putting in a internal threaded plug so a male threaded rod end can be used,

This would be easy to replace when corrosion sets in and allows corrosion inhibiter to be added.

This is what I intend to do when a rebuild is due

[EDMO 1078]

I agree with Dusty - I put 4" long homemade steel threaded inserts into the ends of my struts for the rod ends to screw into. Mine have a 7/16 - 20 thread. I cut the ends of my tubes at 30 degrees to weld to the inserts, and added a rosette weld to each one. I also cross-drilled a witness hole 1/2" from the end of the insert.

I would not trust a welded rod-end.

EdMo

Edited 2 Sep 2015 by Ed In Missouri