Hi all,
First a preface - unless I hear suggestions otherwise, I will just have Vans throw new aileron parts in with my fuselage crate. It's only a few weeks away anyway.
While building my ailerons earlier this month, I read about how misdrilling, twist, or other general misalignment of the steel counterbalance tube was a common point of causing twist in the ailerons in the end. I had none of that. The counterbalance tubes were laid out flat/neutral on my work table. And after drilling, I was able to fit the spar skeleton together with the tubes clecoed to the nose ribs without a problem. Fit on the main skin/stiffener assemblies to the skeleton, no problem.
The problem came when fitting the nose skins on. I could swear the nose skins were really underbent from the factory. Trying to get them to conform was a massive pain. And when I finally did get it clecoed to the spar and main skins, the upward springback pressure of the nose skin popped a number of clecos and really tried to deform the main skins.
I should've probably just stopped there, in hindsight. But I went on, prepped everything, and cursed quite a bit as I forced the nose skin into place while riveting. Put on lots of weight on the main skins to keep down the resultant oilcanning while I drilled the trailing edges, thinking that the wedge would keep things in alignment.
Well, I went to remove my aluminum angle I clecoed to the wedge, to keep it straight, while the RTV sealant I put on the wedge set up. As soon as the angle was off, the skins pulled away from the wedge at the oilcanning points in the skin. See below.
Left aileron:
Right aileron:
I really don't think it's twist, because in both pics, the left edge surface is the bottom skin, which when the whole aileron is laid on a table, is perfectly flat. It's just the top skin that has deformed.
Has anyone else ever seen this? Would I probably be correct in saying it was an underformed nose skin creating springback stress? I'm just trying to get other opinions so the same doesn't happen on the replacements.
Thanks! I'm now going to go find my asbestos flamesuit in the closet.
First a preface - unless I hear suggestions otherwise, I will just have Vans throw new aileron parts in with my fuselage crate. It's only a few weeks away anyway.
While building my ailerons earlier this month, I read about how misdrilling, twist, or other general misalignment of the steel counterbalance tube was a common point of causing twist in the ailerons in the end. I had none of that. The counterbalance tubes were laid out flat/neutral on my work table. And after drilling, I was able to fit the spar skeleton together with the tubes clecoed to the nose ribs without a problem. Fit on the main skin/stiffener assemblies to the skeleton, no problem.
The problem came when fitting the nose skins on. I could swear the nose skins were really underbent from the factory. Trying to get them to conform was a massive pain. And when I finally did get it clecoed to the spar and main skins, the upward springback pressure of the nose skin popped a number of clecos and really tried to deform the main skins.
I should've probably just stopped there, in hindsight. But I went on, prepped everything, and cursed quite a bit as I forced the nose skin into place while riveting. Put on lots of weight on the main skins to keep down the resultant oilcanning while I drilled the trailing edges, thinking that the wedge would keep things in alignment.
Well, I went to remove my aluminum angle I clecoed to the wedge, to keep it straight, while the RTV sealant I put on the wedge set up. As soon as the angle was off, the skins pulled away from the wedge at the oilcanning points in the skin. See below.
Left aileron:
Right aileron:
I really don't think it's twist, because in both pics, the left edge surface is the bottom skin, which when the whole aileron is laid on a table, is perfectly flat. It's just the top skin that has deformed.
Has anyone else ever seen this? Would I probably be correct in saying it was an underformed nose skin creating springback stress? I'm just trying to get other opinions so the same doesn't happen on the replacements.
Thanks! I'm now going to go find my asbestos flamesuit in the closet.
