Countersink or dimple wing walk doublers?

Guy Prevost · #1 07-10-2006, 04:31 PM

So what's the consensus on this? (Like there ever is one...

). I'm trying to decide whether or not to dimple the top inboard wing skin, the wing walk doubler, and the wing walk ribs, or whether to dimple the skin, countersink the doubler for the skin dimples, and leave the ribs alone.

Also, what are opinions on using fuel tank dimple dies to dimple the wing ribs and substructure in general?

TIA,
Guy

DGlaeser · #2 07-10-2006, 05:25 PM

I dimple everything I can and only countersink when there is no other option.
I have spring-back dimple dies, which I used for my tank as well with good results. I'd do a test on plain material (no ProSeal) to see if the tank dimple dies will be to deep - and report your conclusions!

alpinelakespilot2000 · #3 07-10-2006, 05:40 PM

Always dimple unless the material is too thick is my rule of thumb (unless Van's specifically indicates otherwise). A dimpled joint is much stronger than a countersunk one. You won't have any trouble getting flush wing walks with the normal dimpling process anyway. Good luck.

dan · #4 07-10-2006, 07:10 PM

The rule of thumb that I was taught and that I try to pass along is...for AN426AD3-x rivets...

.040" or thinner: dimple it.
Thicker than .040": machine countersink it.