016 vs 020 flap n ailerons

[Billythekid]

I recently got my pickers on a partial rv4 wing kit and have read re read and re ear read the pp and my question is on the older kit like mine circa 1994 the aileron and flap skins are 016. I have read that some of these have been built with heave skins... Is this 020 and if so what's the reason for this. I plan on following directions but must question why the change in skin thickness

[Billythekid]

Is it possible to move this question to general discussion

[RV6_flyer]

Unaware of a change in aileron and flap skins.

Yes Elevators skins were changed on ones that had 180 HP engines as cracks were developing in the elevator skins on the airplanes with larger engines.

[SHIPCHIEF]

My wife's RV-4 got backed into a Tee hangar and the ailerons were damaged.
I called VANs and bought a pair of quick build ailerons for an RV-8. They have .020 skins and fit right on.
I also bought new hinges and took this opportunity to improve the aileron to wing fit.
Total satisfaction.

[JonJay]

Originally Posted by RV6_flyer

Unaware of a change in aileron and flap skins.

Yes Elevators skins were changed on ones that had 180 HP engines as cracks were developing in the elevator skins on the airplanes with larger engines.

Well, that was a prevalent theory back in the day that turned out not to be true.
Lot's of us out there with 180HP and .016 skins in both RV4's and RV6's doing just fine....
The assumption of the day is cracks develop from preload as a result of poor fabrication techniques. This had become a well known issue by the time I built mine and if you follow the plans, it is very unlikely they will crack even if you have a 180HP engine..... 700 hours on mine, and I am sure they will start cracking tomorrow as a result of me writing this !