Dimple or countersink?

[Ron B.]

We cannot find any reference to the dimpling or countersinking of the rear spar. I'm refering to the bottom skin installation. The rivet layout shows 426 rivets, so some form of dimple or countersink is required.
Any help would be appreciated.
Ron

 

[Sid Lambert]

On the 7 & 8 wing they say dimple it and then just touch it with a countersink. That rear spar is pretty thick so just a dimple is not enough.

I used the tank dies and dimpled it. Turned out nice.

 

[rvbuilder2002]

We cannot find any reference to the dimpling or countersinking of the rear spar. I'm refering to the bottom skin installation. The rivet layout shows 426 rivets, so some form of dimple or countersink is required.
Any help would be appreciated.
Ron

Actually dimpling and countersinking are both countersinking.
One is "dimple" countersinking and the other is "machine" countersinking.
Using these designations makes it a little more clear about which operation you are talking about.

On the 7 & 8 wing they say dimple it and then just touch it with a countersink. That rear spar is pretty thick so just a dimple is not enough.

I used the tank dies and dimpled it. Turned out nice.

Sid is correct. Actually, just dimple countersinking is good enough, but if you are looking for an ideal fit of the skin you can machine countersink it very slightly after dimple countersinking.

 

[Harland E. [n.m. u.s.a.]]

Affirmative

I also "touched up" the dimple countersunk holes in the rear spar with a 100 degree de-burrer, worked out nicely.Vans says the tendency is to remove too much material so be conservative.

 

[rleffler]

We cannot find any reference to the dimpling or countersinking of the rear spar. I'm refering to the bottom skin installation. The rivet layout shows 426 rivets, so some form of dimple or countersink is required.
Any help would be appreciated.
Ron

I just finished riveting the skins on my wings and asked the same question when I was where you are at. The answer was to dimple. I used my drdt-2 without any issues.

bob

 

[Ron B.]

Thanks for the information, just curious if it's in the RV-10 instructions and we can't find it or if it's one of those, figure it out yourself, deals?
Ron

 

[RV10Rob]

I couldn't find it in the instructions, either. Mine are QB wings, and the top side was already dimpled, so that's what I did on the bottom.