Wing - Fiberglass

2004-08-07 - Left wing tip. (6.0 Hrs).

I finished the left wing tip today. Well, as far as drilling, filing, nutplates, etc. I still need to paint, but that's another day.

A few days ago, I epoxied the strip of nutplates for the top wing tip screws to the inside of the wing tip. Today, I screwed the wing tip to the wing, and I had a few problems. When I pushed down a little too hard while screwing the wing tip to the wing, the strip of nutplates come loose in a few places. There was not enough epoxy under the strip, and I had not added any epoxy to the edges of the strip, like I had planned to do. This was fixed by gluing the strip back down, and adding some more epoxy along the edges. This seems to be holding ok, but there is a better way.

It turns out that I was wrong about not wanting to rivet the nutplates directly to the fiberglass tip. After the problems with the top strip of nutplates, I decided to try and rivet a nutplate directly to the edge of the fiberglass wing tip, just like the instructions said to do. Since there was no cracking on the first nutplate, I decided to do the whole bottom strip like this. This method took about half as much time as riveting the nutplates to a separate strip of aluminum, and it works a whole lot better.

Countersunk holes in the wing tip edge. Ready to screw the wing tip to the wing.
Error

I was afraid this would happen!

Here's the solution.
Top all done.
Even the front looks good. A little Super-Fill will fix this right up.
Here's the nutplate assembly line for the bottom of the wing tip.
Turn the assembly line around, countersink, and start riveting--very simple.
The left wing tip is all done.
Oops, forgot the rib in the end of the wing tip. Note, due to the nutplates, the end rib is not flush against the edge of the wing tip. Should not be a problem.
All of the nutplates and the end rib installed. The left wing tip is done! I wonder where dufus is.

Oh, one other thing that needs to be done is to add a fiberglass rib or two across the width of the wing tip to give it a little more rigidity. This thing seems to flex quite a bit.