Wing Rebuilding

[SkyPirate]

I haven't read ac 43-13 1b ,..I'm just curious if there is something that brings that attention to the fuselage,..I'd be willing to repair a section with in the fuselage with a splice and an internal or external sleeve,.and feel all warm and fuzzy about it,..the fuselage is a conglomerant of several structural sections,..
And don't take this wrong ,..I'm speaking personally here,..the strut and my knowing the stress's it is exposed to,..I would weld any crack or break close to the ends of a strut,..because vibration is buffered by the connection points of the strut ..which are on each end ,.and the repair would not be exposed to severe vibration,..in the center of the strut,..you have the jury strut which does buffer vibration,.. at the point that the jury strut is attached,..but ..because both ends of a repair in the middle of a strut would be exposed to that vibration ,..more so then an on end,..and welds are very suseptible to vibration,..there is allot going on there at that point ,..wind induced vibration at speed being the major culprit,..personally I would not repair a strut in the middle ,and get that warm and fuzzy feeling ,..I would get a new piece of 4130 and rebuild the strut before welding it in the center.
that is just my personal feeling about it.

[SkyPirate]

point taken,..it is up to the owner,.
I have held certification in all phases of welding ..including nuclear,..I was just stating my own personal feeling concerning a strut.

(I want to clarify something . we are talking about a round strut here ,..not an aerodynamic strut)

Chase

[SkyPirate]

right ,..I was saying the round strut because it is round ..which makes it more suspeptible to the air induced vibration,..a strut that is extruded or formed into an aerodynamic shape has less vibration induced by air flow.
a round strut with a dressing on it to make it aerodynamic has less vibration then just an exposed round strut,..but it is still a round strut ..the added cosmetics does not increase its integrity,..where as an extruded or formed strut is stronger.,.. and yes..more expensive to boot.

[SkyPirate]

yes .that is to make your splice cut on an angle,.and bring the seam to a point,...try your best to never cut a splice joint at 90 degree's ,..unless we are doing pipe fitting for pressures less then 120 lbs psi..but then your welding the same joint at least 3 passes ..a root then fillet then finish

[SkyPirate]

well ,..my not ever reading that article you posted prior to your posting it ,,and what I have said prior to the post gives merit to what I have said,..and after reading the posted article,,I can see it is a little outdated in welding tech.
From what it is saying ,,it is explaining a flame welded joint which will need annealing to relax any weld induced stress,..now I did not look at the link to see if there were any photos of a correct weld application.
If I were to weld anything on an aircraft today,..I'd be tig welding it ,..not flame welding.
Tig welding is 100% perosity free,..and it does not need to be annealed after a weld is completed,..although some still do,..it's an operator option
the one thing in your article that made my sphincter tighten a little was the statement basically saying ..watch the strut during flight for failure ..this is why I would not weld a strut..personally
but it is the owners choice,..

and thanks for posting that article ..it backed up everything I said

[Skybolt]

Does anyone have any experience in fixing wing struts? I have the two long beams that are bent and I guess need eigher replaced or welded. Any have one forsale?

SkyPirate.
It looks like you have vast experience with how a strut can be welded per FAA procedures for airworthiness and probably are very good with the welding (making a quality weld)
This is how I see this thread unfold.
But the question is; can your average kit builder tackle such a job?

Steve, the person who asked the original question is looking on.
Can the long beam be welded. from what I read= No. It should be spliced or a big chunk removed from the center and a new tube welded in.
What If Steve can not weld, he can buy chromoly steel tube, the correct thickness and fabricate the repair, then he can take it to a weldor. But will that weldor take on the responsibility of a job that keeps an airplane in flight?, maybe not.
If I were that weldor I would not take on the job.

I would price the wing strut at Kitfox Aircraft and go from there.

[Skybolt]

airhawg, what are you guys doing with kit planes?

From what I can gather you guys have a wealth of knowledge....A plans built would suite you just fine.
Maybe it's the flying you find the most enjoyable?
I am working on a Skybolt, plans.
Some seriouse thought everytime I work on it, but it is a blast, big difference to the Kitfox, especially the way Kitfox has made the components go together and the easy construction manual. Yeh' I know, a little head scratching but nothing like a plans build.

Sorry to get off topic.
Cheers

[SkyPirate]

My point was ,.. the strut is not an area for some one with limited welding experience to be messing with,..there are too many forces going on that MUST be accounted for ..replace it.

I'd like to add,..because the strut was bent and put downward forces on the spar at the point where it connects to the fuselage,..this area is just as important..check it for stress cracks ..elongation ,..check the bolt for cracks..the attach point on the fuselage for stress cracks .etc

from the photo it looks like the front strut took a pretty severe hit and it was bent more then 30 degrees at impact,..for it to spring back to what looks like 20 degrees plus minus,..the jury strut looks to be still intact..meaning connected ..so the spar was not allowed to flex between the outer strut connection and the fuselage at the impact moment

dang it carnt spell carwreckly edit edit edit

[Steve]

I am still trying to find someone that can do welding in or around Arlington, WA. I am wanting a remake the wing strut useing my existing hardware, which is what Kitfox recongmends. I have a welding job needed on the rear tire brace so I need to find a local welder that I can trailer it to.

[SkyPirate]

Hey Steve,..just curious of the spar was damaged at the fuselage connect points too?