First Mistake on Wings

Naruto · #1 10-13-2007, 07:18 PM

Well, I misinterpreted the instructions and drilled extra holes in the left rear wing spar for some of the wing walk ribs. I should have used the spar to drill the rib flanges but I did the opposite. Think I can just put some rivets in the holes and build on? I plan on calling Vans Monday but was to know what others think.

Chappyd · #2 10-14-2007, 05:15 AM

Ouch. I would email them this picture to so they know exactly what you are asking. I made a ding/smiley in my spar web when I tried to rivet one of the Z bracket nutplates without a solid set up and it got away from me. I sent them a pic that looked worse than it did in person, and was told not to worry and build on. They answered in 1 day. So far I've had to purchase a number of replacement parts. 1 elevator skin ( the trim tab one ), 1/2 of the F706 former, (drilled 5/8 hole for snap bushing in the wrong place) but the worst was when I had a flap fall from where it was stored. Pretty much bent everything. Cost to replace was about $120.00. I had moved it, and before I finished what I was doing got distracted by other stuff upstairs. About an hour later heard a loud crash. Bad noise, lol

I'm no expert by any stretch, but something will need to be done with the 2 holes that break out rear spar reinforcement. Either radius & smooth them out and blend, or just replace it. I think I would replace it cause it looks like you'll need to remove it to try to fix it anyway.

Just remember, you are not alone!!

dan · #3 10-14-2007, 05:35 AM

I agree with Dave. I'll bet Van's will tell you the spar itself is fine, but that the doublers need to be replaced.

While you're at it, it will be a good excuse to flip those rivets around. Rule of thumb: Shop head on the THICKER material side whenever possible.

cytoxin · #4 10-14-2007, 05:36 AM

i would, without a doubt replace them. lets see what vans says.

Bernie RV7 · #5 10-14-2007, 08:35 AM

Quote:

Originally Posted by dan

I agree with Dave. I'll bet Van's will tell you the spar itself is fine, but that the doublers need to be replaced.

While you're at it, it will be a good excuse to flip those rivets around. Rule of thumb: Shop head on the THICKER material side whenever possible.

Dan, now you have me and a few hundred other builders wondering if we have the shop heads on the wrong side of our HS & VS spars ( thats all I have built so far). I was going by the Mil specs I found on your site and they state.... Quote

" 3.3.3 Driving procedure.
3.3.3.1 Head direction
Unless specified on the engineering drawing or specification, the manufactured head of the rivet shall be located on exterior surfaces. "

Cheers

LifeofReiley · #6 10-14-2007, 08:49 AM

Quote:

Originally Posted by Naruto

Well, I misinterpreted the instructions and drilled extra holes in the left rear wing spar for some of the wing walk ribs. I should have used the spar to drill the rib flanges but I did the opposite. Think I can just put some rivets in the holes and build on? I plan on calling Vans Monday but was to know what others think.

Fill the holes with rivets and move on... I'm willing to bet Van's will tell you the same. The (V) in the fork can even be a little larger than Van's cuts it out. I've seen builders in the clean up and debur process remove more material than that hole is taking.

In the days of the early RV's, builders had to taper (cut) the 1/4" aluminum pieces to build the reinforcing stack for the main spars. Then they would have to be filed, deburred and polished. You should have seen some of the variations there. Build on my friend...

Chappyd · #7 10-14-2007, 09:17 AM

Putting a rivet in the 2 holes that have broken through the edge will do absolutley nothing to strengthen the doubler. It would be better to leave them open and radius them out, or at least remove the material past the hole, than to leave an undeburred areas and fill it with a rivet. That would still require disassembly. Would a DAR or the FAA rep buy off on that? That's scary. My plane is far from perfect, but I would not cut corners on a piece who's reason for being there is to add strength to the wing structure. It's really not that big a deal to fix it now, at this point.

I read somewhere in Van's materials that the manufactured head is to go on the side with the thinnest material, which would agree with what Dan said. This is not always possible, but when it is, I do it. Must be a reason for it.

LifeofReiley · #8 10-14-2007, 09:46 AM

Quote:

Originally Posted by Chappyd

Putting a rivet in the 2 holes that have broken through the edge will do absolutley nothing to strengthen the doubler. It would be better to leave them open and radius them out, or at least remove the material past the hole, than to leave an undeburred areas and fill it with a rivet. That would still require disassembly. Would a DAR or the FAA rep buy off on that? That's scary. My plane is far from perfect, but I would not cut corners on a piece who's reason for being there is to add strength to the wing structure. It's really not that big a deal to fix it now, at this point.

I read somewhere in Van's materials that the manufactured head is to go on the side with the thinnest material, which would agree with what Dan said. This is not always possible, but when it is, I do it. Must be a reason for it.

There's not any damage that would require strengthening the doubler. Using a dremel tool make a small radius, debur and leave it alone is another option. The doubler could stay on place. A rivet in the hole is not going to hurt anything either.

gasman · #9 10-14-2007, 12:05 PM

Quote:

Originally Posted by Chappyd

I read somewhere in Van's materials that the manufactured head is to go on the side with the thinnest material, which would agree with what Dan said. This is not always possible, but when it is, I do it. Must be a reason for it.

My guess is, the thicker material will reduce shank expansen and allow a better shop head. Kind of like when you place a washer behind a pulled pop rivet head.

dan · #10 10-14-2007, 12:08 PM

Quote:

Originally Posted by gasman

My guess is, the thicker material will reduce shank expansen and allow a better shop head. Kind of like when you place a washer behind a pulled pop rivet head.

Don't mean to sidetrack this thread, but go ahead and rivet .020" or .016" to say .063" or .125". Try it with the shop heads on the thin side and lemme know what you see...probably "scalloping" between holes.

In this case, with an .040" spar and .125" doubler (at least I think those are the thicknesses, if memory serves), you're not likely to see any of that buckling or scalloping. But on main wing rib flangs, for example, you just might.