Fabricated rudder skin stiffeners. All the stiffeners are punched out to the same size, with 18 rivet holes. Only the bottom stiffener is full length. Each higher stiffener is shortened from the front by one additional hole, going from 18 holes to 11. Normally you mark cut lines based on prepunched holes, but the holes on all thes stiffeners are punched for 18. I used the scrap from the 18 hole stiffener as a template to mark the cut line for all shorter stilffeners, since there are no punched holes.
