cln1owner

Well Known Member
Was working on my right aileron tonight and realised that I'd messed up on the left.
A quick glance at the plans and a few choice words...

mistake_1001.jpg


OK, I see the holes in the rib and spar... flush head 426 rivets, bam countersink the spar? Oh, ****, did I countersink the spar?
Any way to recover from this, or do I just order a new spar?

Instead of match drilling the reinforcement plate and countersinking the front of it, I quickly assumed that only the spar and rib were riveted together, and I countersunk the face of the spar. Can I get away with matching and countersinking the reinforcement plate now and riveting? Will the missing material of the countersunk hole in the spar cause problems?
 
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Call Vans in the morning but I suspect that it is fine and you can just keep building. I dimpled those 4 holes on each of my spars (-7 but looks the same) but the spar seems thick enough to counter sink. Did it countersink down to a knife edge, or is there still some of the spar thickness that is #40? I think that you could leave those AN426AD3-4 rivets out entirely and the bolts that hold the bracket on and the rivets through the top and bottom flanges would be enough to hold that rib on.
 
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Just dimple the nose rib and the doubler and not the trailing rib. Do a test dimple first on similar material and thickness as the doubler to make sure you get an acceptable dimple on that thicker material.

Another option is that there are some countersink filler doughnuts available to fill in the void on occassions like that.
 
Not a Problem

The spar is sandwiched between the reinforcing plate and the rib and also clamped by the bolts. In this instance, the rivets are more for alignment than anything else. "Build on."
 
Thanks for response guys,

I'll go ahead and drill the reinforcement plate and move on. I would still like to fill the gap with something. Brian, I've done some hunting but can't find those countersink filler doughnuts you spoke of. Where have you seen them?
 
Oops rivets

Thanks for response guys,

I'll go ahead and drill the reinforcement plate and move on. I would still like to fill the gap with something. Brian, I've done some hunting but can't find those countersink filler doughnuts you spoke of. Where have you seen them?
If concerned about missing material you can put in 'oops rivets' instead of 3-4. Enlarging the hole to #30 should take care of the majority of the countersink. Either way, as stated by the DAR, they are just for alignment. The Bolts do the work.
Mike H 9A/8A