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Michael Brown

Active Member
What do I do? I used my tank dimple on my leading edge wing skin. I took a piece of scrap and dimpled with the tank dimple then back over it with a regular dimple. I can't really tell a difference. What do you guys think?

I guess I was due for a mistake.... Its been a while.

Thanks
 
Relax...should be just fine, you talking thousands of an inch difference...your drill bit didn't have that close of a tolerance when you match drilled and deburred the hole. As long as the dimples sit flush wihin each other all should be OK especially for just one hole.
 
Dimple Over?

Not just one hole..... The whole skin. The rivets sit a little deeper, but I am thinking no one will ever notice. Should I go back over them with the right dimple?
Thanks
 
Michael Brown said:
Should I go back over them with the right dimple?
Thanks
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Won't do any good - the tank dimple die is every-so-slightly larger than the regular dimple die. The dimple is already larger (by a couple thousandth's of an inch) than the regular dimple, so going over it again with the regular dimple die will do nothing.

Your flush head rivets will sit a little deeper perhaps, and expand to fit the area slightly. By the time you've got paint on it, no one will be able to tell.
 
davidkarlsberg said:
what about riveting it together with proseal? Not sure if that is a good idea or not but it is just a thought.
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I had to laugh at first but then got the jist of it...that's why they are a little deeper, to allow the rivet to sit flush with Proseal around it. I recall I heard that some builders use the tank dies for the entire build. Allows the rivet to better fill the dimple a bit more flush and makes a better looking rivet line...not sure If I got that right though...I still don't think its a big deal. If your rivet line is on the spar, make sure the countersinks are another shave deeper to allow for the ever so slightly deeper dimple.

But I'm not an engineer...so maybe one will chime in.
 
Michael Brown said:
What do I do? I used my tank dimple on my leading edge wing skin. I took a piece of scrap and dimpled with the tank dimple then back over it with a regular dimple. I can't really tell a difference. What do you guys think?

I guess I was due for a mistake.... Its been a while.

Thanks
Click to expand...
This is kind of where an "experienced" builder like me laughs at the over-anxious "newer" builder worrying about everything way too much. I don't laugh too much though, because I remember being there too! :eek:

Seriously, relax. I can't imagine anything problematic about this and doubt that even most experience builders would be able to pick it out. Whatever you do, though, don't try to flatten the original dimple in order to redimple it with the regular die. That will just weaken the aluminum.

Good luck.
 
airguy said:
Your flush head rivets will sit a little deeper perhaps, and expand to fit the area slightly. By the time you've got paint on it, no one will be able to tell.
Click to expand...

Greg has got it correct, by the time the paint dries you, much less anyone else, will not be able to see the difference.....move on;)
 
Thanks guys..... I did dimple the ribs with the right dimple. Should I go over the ribs with the tank dimple so they match?
 
Whenever I dimpled both the top and bottom items with the same dimple die, it looked like there was an ever-so-slight gap between the aluminum parts. This was easily observable where two edges came together.

My solution was to use the "tank" dimples on the lower part and "normal" dimples on the top part. This allowed the parts to nest nicely...IMO.

Recently, there was a link to a "how to dimple" animation (I think produced by Disney's studios for the WWII build efforts). This showed that each succeeding layer of aluminum gets a slightly different dimple geometry so that all parts can nest properly. In effect, this is what the tank dimple dies and normal dimple dies accomplish.

In your case, I would not change anything. Leave it the way it is. But if it really bothers your sense of aesthetics, then leave the tank dimples on the ribs and only change the skin dimples to the "normal' variety.

As an aside, some number of years ago I attended the Oregon State EAA convention. There was an RV-6 there that I sworn had composit wings...they were that smooth. The owner/builder/pilot stated that he purposely dimpled the wing skins slightly deep. He thinned down some pro-seal and dabbed it onto each rivet head, and smoothed it down to the skin surface. After painting, the rivet lines completely disappeared. The wing was truly as smooth as glass.
 
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