Strut attach fittings. Clunk-clunk

[Dano"T"]

Re: Strut attach fittings. Clunk-clunk

DanoT,

Do the cracked wings have tube installed between the front and rear life strut attach fittings just above the lift strut attach point?

There should be a tube installed there and it has a long wire with threads on the ends that goes thru it and hold it in place as well as keeping the strut attach fittings pressed up against it.

Dave

Yes....and that compression strut is a little loose....and the cracks are longitudinal ( with the grain as I see it ) still need to cut a hole and verify that these are the cause if the clunking. On The inspection camera....they look like cracks.

[Dano"T"]

Re: Strut attach fittings. Clunk-clunk

DanoT,

Do the cracked wings have tube installed between the front and rear life strut attach fittings just above the lift strut attach point?

There should be a tube installed there and it has a long wire with threads on the ends that goes thru it and hold it in place as well as keeping the strut attach fittings pressed up against it.

Dave

Yes....and that compression strut is a little loose....and the cracks are longitudinal ( with the grain as I see it ) still need to cut a hole and verify that these are the cause if the clunking. On The inspection camera....they look like cracks.

[Guest]

Re: Strut attach fittings. Clunk-clunk

Yes....and that compression strut is a little loose....and the cracks are longitudinal ( with the grain as I see it ) still need to cut a hole and verify that these are the cause if the clunking. On The inspection camera....they look like cracks.

Hi DanoT,

I am just trying to clarify but the tube that I was describing is not a compression strut.

Did you think that I was referring to a compression strut?

Dave

[Dano"T"]

Re: Strut attach fittings. Clunk-clunk

Oh...I assumed you meant the compression strut...I will go out and look

[Dano"T"]

Re: Strut attach fittings. Clunk-clunk

I see....that tube is there...i hear clunking when I move it up and down, but it does not appear to move. I tried to inspect what I thought were cracks a little close and I'm perplexed. It looks like a perfectly longitudinal crack but I cannot get a feeler gauge or an awl into it....could be a scratch? I simply can't find any loose fittings, struts, bolts, or any compression cracks. If I hold a compression strut and try to flex the wing it doesn't clunk....my wife thought it was the aluminum skin buckling....I don't think it is. Hmmmmm

[Hank Jarrett]

Re: Strut attach fittings. Clunk-clunk

Harbor Freight sells a thing that looks like a Doctor's stethoscope with a wire on the end instead of that freezing cold disc they put on your chest. GREAT for listening to turning bearings or isolating where a sound is coming from on parts. You can use it a lot like a sound direction finder by making the part click while holding the wire against different spots. Takes a couple of minutes but you can trace the sound by how loud it is in the ear plugs.

Hank

[Robert Lees]

Re: Strut attach fittings. Clunk-clunk

Dano:

Could your "crack" be a lamination join? My 46 spars were laminated (longitudinally across the grain) and from quite a few pieces of lumber.

[Dano"T"]

Re: Strut attach fittings. Clunk-clunk

It could be a lamination. I am not certain....I have to locate the source of the noise ...I watched the supposed "cracks" while someone flexed the wing and there was no change in the " crack"...it didn't widen or c.lose...and the noise is pressmen if I push upward on any of the four spars....maybe I'll check all of the brace wires....if one was loose or broken I bet the wing would flex torsionally enough to buckle the sheet metal or something....

[3Dreaming]

Re: Strut attach fittings. Clunk-clunk

Like I said earlier I have seen an elongated hole in the fuselage strut attach fitting be a problem. When it moves the sound resonates from the forward wing strut attach fitting.

[Guest]

Re: Strut attach fittings. Clunk-clunk

I like Tom's idea.

Lift the wing up and down and feel for movement at the strut ends.

Dave

[Robert Lees]

Re: Strut attach fittings. Clunk-clunk

The wing-to-fuselage bolts are close-tolerance bolts. So AN173, AN174, AN175, AN176 -dash number bolts.

Well not AN173 in this situation, perhaps, but you get the idea!

Rob

[Dano"T"]

Re: Strut attach fittings. Clunk-clunk

Nope, not at the fuselage....doesn't move. I don't get it

[Guest]

Re: Strut attach fittings. Clunk-clunk

check at the other end of the struts then

[Dano"T"]

Re: Strut attach fittings. Clunk-clunk

Wow....DRude was right after all....I switched places with my helper and looked at the fuselage end....saw no movement...got frustrated and grabbed a 1/2 socket and...........the bloody things were LOOSE! Not enough to notice, but when I tightened them a bit.........no more clunk. I will replace said bolts and fly tomorrow....the spars were laminated and appeared cracked at first...I have now inspected and photographed every inch of all four spars with the $30K snake camera from work......I'm both embarrassed and relieved. Wheeeew!

[3Dreaming]

Re: Strut attach fittings. Clunk-clunk

Wow....DRude was right after all....I switched places with my helper and looked at the fuselage end....saw no movement...got frustrated and grabbed a 1/2 socket and...........the bloody things were LOOSE! Not enough to notice, but when I tightened them a bit.........no more clunk. I will replace said bolts and fly tomorrow....the spars were laminated and appeared cracked at first...I have now inspected and photographed every inch of all four spars with the $30K snake camera from work......I'm both embarrassed and relieved. Wheeeew!

Tightening the bolt just mask the problem. If you are lucky the bolt will fix the problem. If not the hole in the fitting is elongated. If I have time tomorrow I'll shoot a picture of what I am talking about.