is this normal?

[ken nougaret]

For a KF with only 7 hours, is it normal to see wear on the forward spar doubler? It's grooved the RH side. Not so much on the LH.

[jiott]

Is it possible that the top edges of the vertical tube sticking up from the front carry-thru tube has sharp edges. This combined with a very tight fit would plough a small groove in the doubler every time you swing the wing into position. Round the edges slightly and loosen the fit just enough so that it takes the paint off but not much else.

[Dave S]

Ken....Agree with Jim on the analysis...I think all you are looking at is a little minor fit & finish operation with a file to better match up the curvature of the end of the vertical tube which the pin slips through with the curvature of inside of the spar doubler. The spar tube should slip over the pin tube with little resistance; but, you don't want to remove so much material that the spar can move up and down on the vertical tube. When the wing is rotated away from the fuselage - the front spar may sag a bit when nothing is supporting it so when swinging the wing back on a person might find it useful to observe the alignment as the parts fit back together.

[jrevens]

Surely you wouldn't have folded the wings very many times in only 7 hours? It looks like the paint is pretty thick in there... is it mostly just paint worn off, or is there an actual grove worn in the metal? It seems unlikely that the metal would be more than just a little scratched or scraped in such a short period of time.

[ken nougaret]

Surely you wouldn't have folded the wings very many times in only 7 hours? It looks like the paint is pretty thick in there... is it mostly just paint worn off, or is there an actual grove worn in the metal? It seems unlikely that the metal would be more than just a little scratched or scraped in such a short period of time.

I measure .032 dig into the aft side of the doubler. All other areas are o.k.
It's not difficult to open/pin the wings. It's as expected; a small lift or just a good push and it slides on.

[efwd]

Consider the surface roughness of the steel where you filed the steel away to make it fit. Looking at mine I may need to polish it so that the file marks aren't too abrasive. Could act like a file in itself.
Eddie