Fixing Broken Flap Gap Seal (wiper)

By Mark Taylor



Okay, somehow I managed to hang a wiper when I was bringing the flaps back up. There was a crunch noise and little bits of the gap seal went flying.  Here is my first attempt at fixing this in step-by-step detail.  Note: I am just an average builder, so your results may turn out far better than mine. But this should give other rookies a hint at the steps that will fix it.


Click on pictures below for larger picture.
I'm missing about a 3 inch segment near the flap control horn (which is driven from the top on this plane.  I removed (unscrewed) the control horn from the flap. 
I stretched a piece of thick tape across the wound on the outside of the flap. 
Since the tape doesn't appear to be strong enough to form a mold by itself, I'll need a stronger former.

I found a cardboard tube with a 1/2" inner diameter (aprox same as curve). I cut the so that I had about 1/3 of a circle.  ps-this tube happened to come from the center of a roll of stick-on sandpaper.

Here I am positioning the former against the flap checking for proper curvature. I taped the former in place here.
Now I have to get the wing in the proper orientation. Here I have it proped up with leading edge up, and flap bent back about 100 degrees. This will make it so when I pour resin it will pretty much stay put.
15 minute epoxy and microbaloons mixed up to about the consistency of applesauce.
I have put some tape on the wing skin, so that I don't goop some resin on it.  I've put a very healthy amount of goop to fill the wound, actually probably too much, oh well..

I let the resin kick in this position.

After the resin has kicked, but while it is still green, I removed the cardboard and tape and tucked the seal under the top skin to make sure of proper fit. I taped the flap in place and let finish curing with flap down about 30 degrees (edge of gap seal just under top skin).
The resin has now cured and I'm sanding flush with the rest of the gap seal.  Other than a slight color difference the repair job looks good.