What should be a job of just installing the handles with 2 screws became a longer job.
The threads in one hole were damaged:
First idea was to install a M5 Helicoil:
However upsizing to M5 reduces the edge distance to less than 2x D in the angle profile:
A better solution is to drill through the damaged hole, fill it with epoxy resin and re-drill to install a M4 stainless steel bushing:
The bushing was fixated with epoxy resin:
Multiple iterations of filling and sanding were required. an oven was used to speed up the curing of the epoxy filler:
The handles do not perfectly follow the profile of the fuselage. With some epoxy resin applied to the back of the handle, it was installed and the squeeze out resin removed. To prevent the resin sticks to the side skin some aluminium tape was used which was applied over blue painters tape for easy removal:
After another round of sanding, filling and painting the handles could be installed:
Nylon washers were glued to the bolts. This will make life easier when the handles need to be removed or installed when the inside skins are installed as well:
Job done:
