Trim tab

The last couple of days brought mixed success with the trim tab. Got the inboard tabs folded and was pleased with the results.

TT inboard tabs folded

The outboard tabs didn’t come out so well. They looked ok, but not great – sorry, no pics.. Got everything put together, then clamped the piano hinge into position and match-drilled it to the spar and skin. This is where things began to go south a bit.

The plans call for a 1/4″ distance between the front edge of the hinge plate and the match-drilled holes. This leaves exactly 3/16″ edge distance between the center of each rivet hole and the aft end of the hinge plate – and that’s the absolute minimum for #40 hole. The clamps must’ve needed a few extra turns, because the whole assembly slipped a bit and some of the holes didn’t have the required edge distance.

So, it was time to order a new hinge. And since I was ordering parts from Van’s, I decided to order another trim tab skin – just to see if I can do better the next time around. I may just cut off the outboard tabs and fabricate another riblet to take their place.