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Dimpling Screw Up

G

GTechRV

Active Member
I've already sent this along to Vans but I wanted run this by you guys.

Long story: So I was dimpling a hole in the h-stab with the c-frame when I hammered my finger real good. After nursing the finger, I hit the c-frame again not realizing the skin came unset from the dimple die.

Short story: I'm stupid.

Either way, I've ended up with an "extra" hole in my h-stab skin. Image below. Can this just be riveted shut, or do I need a new skin? I appreciate your guys expertise.

im_stupid.jpg
 
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I agree that putting a rivet in is the way to go. However, be sure to closely inspect the new dimple to make sure a crack didn't form.
 
Will anyone who has NOT done this, please raise their hand?!

Ahah....that's what I thought - You're not alone Ryan! Put in a rivet and move on....

Paul
 
These are commonly called "rider rivets". They just go along for the ride. If anyone asks what the rivet is for, just look at them funny and say, "Your not a builder, are you?"
 
Ryan

Thanks for allowing me my chance to take a walk down my memory lane of interesting build happenings. Great suggestings by others...............I have used the DRDT-2. Yes it is pricey but does a great job. My Avery c-frame is collecting a lot of dust!

Frank @ SGU RV7A...NDY!!!!!!!!!!!!!!!!!!
 
:D You guys are the best (no matter what they say on tv). I do remember seeing this on others build logs, just never paid attention to what to do about it. Still I'll admit I was a bit panicked when I realized I did it.
 
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We all have them! You can always bondo over that rivet and nobody will ever know about it. My most recent was an extra dimpling of the trailing edge of my right wing skin.

My son is heading to Tech in the fall.
 
+4 technical points for near perfect symetry with surrounding rivets.

+4 style points for putting it in the middle of the skin instead of that boring "dimple-8" most of us do

0 presentation points (I penalized you for not removing the blue stuff before taking the picture)

Overall an 8. Nice job!
 
Could be worse....I let one of the neighborhood kids dimple the screw holes in my fuel tank skins. Same story, he couldn't hit the C-frame hard enough, so he hit it twice, and the skin moved between hits. Ended up with an extra hole in the top of my fuel tank skin.

PJ
RV-10 #40032
 
First of all, everybody has done this. However, since this hole was poked rather than drilled, you might consider running a 1/8 drill through it to remove possible cracks, and then using an oops rivet instead.
 
How I fixed mine

I have a large 22" bench mounted yoke I borrowed.

I was too cheep to get the foot control for my squeezer for just so many hundred holes that needed to be done, so I had my son help by being the dimpler while I set the skin. After developing a good rhythm, I hesitated at the next hole for a good line up, he didn't wait for my verbal "OK" :eek: and wa la I had a punched and dimpled hole on the bottom O/B wing skin.

My fix was, since it had cracked. I knocked the hole and dimple area out with a Whitney punch, countersunk it slightly from the wrong side, installed the skin on the wing, and then put some met-all epoxy in the hole and clamped a piece of flat aluminum over it.

I forget what I put on the overlay to keep it from getting stuck?

24 hours later, peeled the overlay off, and had a flawless hole filled, no extra rivet in an area that would not have worked out well.

It will paint over and be indistinguishable afterwards. :)

Fortunatley yours is in an area that installing a short rivet to plug the hole should pose no problems.
 
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Me too...

Yeah OK. I did one of those too :rolleyes: (one so far... long way to go in my build).

My luck was that it was on the *bottom* an elevator. Not easy to see...

Does give you that sinking feeling though, doesn't it?
 
done that!

Been there done that! Your actually very lucky since you just made and extra rivet hole that not near anything and has plenty of edge clearance! The absolute worst is when you do that right next to a dimple creating a figure 8 hole!

As mentioned run a #40 drill thru it deburr and check for cracks. If you find some then move up to a #30 and and opps rivet.

Build on!
 
I have one of those extra rivets too. Mine, however is based on extensive structural engineering analysis I conducted; determining the HS needed one more rivet in that exact location. (At least that's what I tell everyone.)
 
Thanks for all the tips and reassurance! I love the "extensive finite element analysis" excuse. And yes - sinking feeling. Big time. Especially since I thought the build was going rather well.

When I pulled away the vinyl coat, I realized that the underside of the dimpling looked real nasty - possibly cracked. I took the # 40 bit to it, then dremelled of the underside of the dimple. After then sanding it down with a 400 grit wet/dry sandpaper, I was able to see that there were no cracks after all (or I had deburred them away). Best part is, I can still use a flush AN426AD3 rivet. Whew.

im_stupid_fixed.jpg


Notice all the scratch marks on the aluminum (and the scuffs left by sanding). I think at the least these need an alodine treatment.

One more thing I was wondering though... is it possible to dimple too much? When I do a little quality control (insert the rivet into the dimpled hole and run my finger over it) some are sunk (minutely) deeper than others.
 
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Re: "dimple too much"

By "dimple too much" do you mean dimple using too much force? I don't think that's possible, at least not using the C-frame/mallet or hand squeezer methods (I've never used a pneumatic). But it is possible to dimple using not enough force, and that might be your problem if you're seeing inconsistent dimples. When you dimple you should feel the die really bottom out, preferably in just one good strong whack/squeeze. If it doesn't bottom out then the dimple and the skin around it could become a little deformed, and then the rivet won't sit quite flush.

p.s. Like so many other builders, my first f*** up on the project was a classic "dimple 8" on the HS skin. It's like an initiation for new builders. So consider yourself lucky, and carry on!
 
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