Starting On The Ailerons - N622RV Today in the shop, I started on the Ailerons. The only thing here I can say is to make sure you have bits for drilling steel. The instructions ask that you use the holes in the skins as pilot holes. Use them as the holes to guide your punch but don’t try to drill them while still attached to the skin. The Carbide or Titanium drill bit you use to drill the steel will tear up the skin if you slip.