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Riveting wing leading edge assy

Hi Folks,

My name is Andre and I'm building an RV9-A in Brazil. This is my first project so you'll always see me here with questions.
I finished the assembly of the wing leading edge, so it's time to rivet it to the main spar. The problem is that doing it is very difficult because the bucking bar access is very tight and we cannot see the rivet end. Is there any other way to do this? A POP rivet can be used?

Thanks in advance for all answers and comments.
 
build up a bucking bar

take a 2"x3"x1"or so bucking bar and build one end up with tape so that it sits just high in the end that will be on the shop head. (the tape is not on the shop head end.)then lay it flat with the 2" side on the soon to be shop head and shoot. this method removes most all of the difficulty of this task. its self-leveling and works like a charm.

some builders choose to use pop rivets..there is no need but works fine i hear.(lp4-3s)

you've got alot of blind riveting to do so you need to figure this out sooner than later.
the first one kicked my tail the second one was not a problem at all. went from almost impossible to no problem.



 
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Van's told me LP4-3 (or LP4-4 as appropriate) or Cherry Max. I ended up alternating CherryMax with the LP4's, though I probably should have saved myself the money and just used LP4's. Given the potentially significant damage you could do trying to buck them, I'm an advocate of just using pulled rivets here. I know some people have done just fine bucking, but I didn't see the need to tempt fate. Good luck.
 
LE to spar rivets

I could do all but one rib, basically the dead center one. I used cherrymaxes. It took some wiggling and chasing a few with a #30 bit, the cherrymaxes are up at the upper limit of diameter(mine were at or over by 0.0005"). Pounded my head over those for a couple hours before spending the $6 to make it go away. Lesson learned!

Rick 90432
 
Here is the reply I received from Ken Scott when I inquired about using Cherrymax blind rivets for this job a couple years ago:

"LP4-4 rivets would be acceptable, cheaper and easier to set."
 
Aren't structural rivets required here??

I guess I am surprised that Vans would say that you could use LP4-3s or -4s?

I would think that using cherrymax rivets for this application would be the best overall solution here. So they're a little more expensive. Big deal. Compared to the hassle of trying to buck the other rivets with the high potential for deforming the rib flanges and just plain screwing up the rivets themselves... this just seems like the logical way to go and leave you with peace of mind on the integrity of the structure.

How have the other 5,000 RVs fared in this regard?
 
I used LP4s after a call to Van's. Tech Couns gave it a thumbs up as well. Dan C. documented this on his site years ago, and his beast is still going strong!

Joe
 
Well, I am certainly no engineer that's for sure. It's just my naivety (spelling?) coming into play here.

I suppose the real strength in the structure is the entire assembly riveted. It just seems as though anything attached to the main wing spar should be attached with structural rivets. Just my non-engineer mind thinking though..

I am not complaining mind you though. It just seems too easy!
 
I know this is a very old thread, but I'm getting close to ready to rivet on the wing leading edge ribs to the spar. It looks like access is a bit of a nightmare and since you have to put the shop head on the side of the rib flange I wonder about how badly the thin flanges will pucker. After reading a bunch of threads on it, I thought I may as well use LP4 pulled rivets and save myself the pain. It sounds like a lot of people have gotten the thumbs up from Van's to do this, but as a double check I emailed Van's. I just got a response from tech support that was basically "we haven't tested it for strength, so I can't say that you can do it." Now I'm waffling since it sounds like Van's is even back and forth on it.
 
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Don't give up! I did mine solo (small hands and arms help) with solid rivets. Tools needed: 3/4" x 1" x 4" tungsten bucking bar, 12" (bit shorter may work) long rivet set (couldn't get an offset rivet set to work), Snap-Soc rivet set caps (these keep the rivet set from moving around too much when driving rivets). The 12" rivet set allows a small angle between the rib and the rivet gun. A normal 3" or 4" has too much angle and the rivet set will try to bounce off the rivet head. The outboard ribs are easy, use the lightening holes in the spar for bucking bar access. The inboard ribs are difficult. I ended up making a wooden guide for the tungsten bucking bar to pre-align it to the rivet shank. A helper with small hands/arms would be ideal. BUT...if you install the Vans stall warner (and you should), it comes with a template to cut an access hole in the inboard lower skin. Buy an additional doubler and stall warner cover and install this on the opposite wing. You now have much better access to the inboard rib rivet shanks. I discovered this AFTER I had completed the riveting as the Vans stall warner was available some time after I'd done the riveting.
 
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