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There I was, happily plodding along, making wing parts as I wait for my back-ordered, (Legacy issue?), control group sub-kit. The rib gussets on page 20 (w16-07 & 08)and page19 (w15-06 & 07) show similar, if not exactly the same, bend tangency lines. Based on that assumption, I bent all the flanges on the same tooling with the same gauging.

Let me now state that matched-hole construction could have once again reared it's ugly head and bitten. Because both the rib and gusset have factory holes burned into them, if the spar-side flange of the gusset is not bent nearly spot on, the holes will have a mismatch related to the placing of the bend.( IMHO, only one of the components should have holes that could easily be transfered to the other. In fact, the print states the holes are to be transfered from the gussets to the rib.)

As always, it's better to be lucky than talented. The holes for the aft rib/gusset (pg. 20) lined up very well with only a hint of mismatch. On to pg.19, where the upper gussets were a near perfect match for the forward rib holes.

The W15-07 fwd lower gussets weren't even close. All had barely 1/3 of the hole matching. All the 07 gusset flange measurements were within a couple of thousandths of each other, and the other gussets. Measuring from the bend to the rivet hole gave a dimention .040" greater (farther away from the spar) than all the other gussets, which indicated to me that the holes were misplaced on the blank. In fact, if you measure the hole-to-edge distances of the blank on the print, they are indeed the offending .040 further away from the edge than the other three gussets.

Would not have mattered if A: Either the gussets or ribs had no holes. Or B: Had I been aware of the different placement of the holes, I could have adjusted the bend accordingly.
Replacement parts have been ordered. Hopefully not a back-ordered Legacy thing.
Still waiting for the engineers to get their diploma here at Area 51%

I am just hitting this plan sheet now. Fortunately, I do not have the matched hole kit parts so only the gusset blanks have holes for me. I see your point - in order for the holes to line up and the gusset flange to be snug against the flange of the rib, your bend would have to be very accurate and precise. It does not make sense that the ribs would have the matched holes for the gussets there.

Do you know how you are going to bend the gusset flange on the replacement pieces so the holes are aligned?

Kevin

When I screwed up my gussets and had to remake them, I used a piece of oak board with a radius on one edge to bend them over. Clamped them down tight and pounded them over with a mallet.

My two cents - your mileage may vary.

I started doing this last night, and is not a problem. And since I do not have matched holes on the ribs, I will not have the hole alignment issues that Area 51% experienced. I was noting that it would seem difficult to get the flange bent so that it was both snug against the rib flange and have the matched holes perfectly aligned.

My gussets did not have holes on the rib-spar-attach side. It was easy to bend, clamp in place, and transfer the holes from the rib to the gusset.

Likewise, the gusset attach holes were not on the body of the rib - again, easily transferred by clamping in place.

Yeah, same as me. Just not sure how well that's going to work out for the matched hole folks. They'll just need to be extra precise with the gusset flange bends.

I've been having a hard time following this. Do we mean W19? F19 is a fuselage page. If we are talking gussets for ribs 1-5 and root ribs I had no issue with my predrilled holes. I think that was just for the root ribs though.

Oh...Ha, yeah. Probably should have been W19.

Area 51%:

I came up with an idea that would help get that gusset flange bend in the correct place, even if all the holes are off like you said. Now of course, you may not need this tip as you are getting replacement gussets, plus it sounds like you have a pretty good handle on how to do things. But here it is:

https://youtu.be/vr0B5gth9KY

Kevin

Great tip Kevin!


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