Wing Attach Fitting Welded In Wrong Spot

[Aaron Novak]

Ah jeez, people always have more confidence in me than I do, myself!

That should be a good thing right? I am betting that some careful use of a dremel cutoff wheel will have that strap and mount taken off in no time. I would slice off the mount, then gently cut while peeling off the strap so as not to cut into the tubing underneath.Once the strap is off, clean up any remaining weld then start over with a new mount and new strap like nothing ever happened. In the end I think you will have more confidence this way, and it will go a lot faster than you think. Since you are not touching the base cluster, I am very doubtful that there will be any distortion. Good Luck!

[martymayes]

Tony, how does the other side fit up?

[TonyG]

Aaron, I'm definitely going to need to stare at the fitting for a while to work up my courage to do it, but you may be right. It's a heck of a thing to pull the trigger on, that's for sure.

Marty, I didn't get the opportunity to check the fit of the other side last weekend, but the spacing measured correctly when I checked it a while back. I'm planning to go out to the hangar again this weekend and will see how good or bad that is. I will say that the rear fitting on the left side is noticeably aft of the fitting on the right side. It should be in the right spot.

[Aaron Novak]

Aaron, I'm definitely going to need to stare at the fitting for a while to work up my courage to do it, but you may be right. It's a heck of a thing to pull the trigger on, that's for sure.

Marty, I didn't get the opportunity to check the fit of the other side last weekend, but the spacing measured correctly when I checked it a while back. I'm planning to go out to the hangar again this weekend and will see how good or bad that is. I will say that the rear fitting on the left side is noticeably aft of the fitting on the right side. It should be in the right spot.

Ten to Twenty minutes to remove it and prep the area for welding, another hour to form up a mount and strap, welding it on. Most stumbling blocks in projects are purely a figment of our imaginations, and once we get over that and start working, we suddenly realize our own ability. Go for it

[TonyG]

It will be next weekend before I can think of tackling it, but I'll try to convince myself it won't be that bad in the mean time. Seems to me like the cleanup will be pretty lousy. Those weld beads go over some pretty strange shapes. My main worry is taking off too much or otherwise compromising the good material which may or may not be visible or fixed when I re-weld the fitting and strap. Maybe I'll make up a test coupon to see how easy and controllable it is to do such an operation...

[Frank Giger]

Aw, it's just another "deep breath" moment in building, where we all hem and haw and look at it and think and then hem and haw some more - and then at some point we just dive in and do it.

And it works out okay.

Oh, and your comment about others having more confidence in your abilities than you do? That's pretty much the easiest way to spot a quality leader who doesn't realize he's leading.

[MCD]

Hope this isn't to late...Looking at the incorrect fitting arrangement this is what I would do and it should be easy. 1) Make a new tab which you will weld onto the fuselage side (same thickness as the original tabs. 2) Weld it to the fuselage tube outside of the lower wing tab (per the photo) 3) Use a spacer between the original tabs and...4) if space allows use two bolts so that the upper two tabs can be compressed and likewise the lower three tabs and spacer can be compressed. From the phto t looks like there is plenty of room.

[TonyG]

Thanks for the encouragement, Frank, though I think I will take your last sentence with a grain of salt!

MCD, not sure if I've interpreted your proposal correctly, but I've drawn it up as I understood it. Is this what you're going for? I guess my concern with this arrangement would be transferring the load from the new rear tab into the fuselage truss - it would probably be fine, but would add a (limited) concentrated loading point right into a tube whereas the original design spread it over a larger area with the finger plate (not shown).

[TonyG]

Aaron, I headed out to the hangar this afternoon and, among other things, inspected my fittings to see what I was up against. Of course you're right, as it looks like it won't be nearly that bad. Inspection (and verification with the plans) shows a decent gap between the wing fittings and the fuselage, welded only at the top and bottom edges. Should have plenty of room to cut without needing the hand of a brain surgeon. I think I can get away with just cutting out the fittings themselves* and leaving the straps intact. This will save me the big concern of possibly grinding into the tubing to peel away the conformal 0.065" straps. Then I can just put a new strap on top of the old strap ends after cleaning up the weld beads so my new strap fits down snug.

*plural - gonna have to do the same to the left side, but not as bad.

Picture showing gap and (lack of) weld, for reference:



-Tony

[martymayes]

Tony, just curious: Do the plans show the wing to fuselage fittings mating up like your photo and sketches? That is, one tab inside, one tab outside the tabs on fuselage fittings? I would think they would fit with both wing tabs inside or outside the fuselage tabs but I could be wrong (again). Also, are those the actual size bolts that will be used?

I think I would just install spacers and let that give it some character. Chalk it up as builder tolerance. You and aeromike have some pretty cool Ray Stits projects going.