RE: Reconditioning an Ultra Stick
The wing tip had to be repaired prior to re-sheeting the leading edge. The wing tips are a bit more complex than on some wings due to the construction. I suppose I could have made a "clipped" wing Ultra Stick, but my goal was to make it look as close as possible to the way it came out of the box. The final wing rib had been damage and had to have that back third cut out. The tip is actually the final rib with a balsa doubler/spacer sandwiched in between the formers that hold the actual wing tip piece. This doubler is three pieces, one runs from the leading edge to the front former and one runs from the front former to the back former. The third piece runs from the back former to the trailing edge of the tip and has yet another doubler glued to it, this time made from light ply. This helps give the trailing edge of the tip a bit more strength.
I cut the doubler that runs from the the back to front former back to about 1/4 of the way from the back former. It had been completely destroyed near the tip, but I cut back far enough to get a decent amount of undamaged rib showing. I then cut a replacement piece for the latter part of the rib and the remainder of the middle section of the doubler. The doubler piece overlapped the joint on the rib with enough on either side to make a good strong bond. I then cut the front and rear tip formers and the trailing edge balsa and light ply doublers. After sandwiching the two doublers, I glued them to the rib. In the picture, the tip formers and the tip itself are friction fit with a bit for tape to help hold it. This helped line everything up properly. After that, the tip formers and the tip itself were glued into place. You can see a bit of overhang at the trailing edge to the tip in the last picture. This was trimmed with a hobby knife then sanded.