The car is 20 years old and was kept near salt water in south Florida. The passenger's side front handle simply broke off one day. The plastic piece that came off in my hand is rotten from age and salt and sun exposure. A factory replacement costs a couple hundred dollars because of labor. The door must be dissasembled to replace the handle and it has power windows and door locks.
I tried reattaching the piece with Gorilla Glue, plastic glue and 2-part epoxy. None worked. Gorilla glue adheres well, but has no strength when pulled on. The other 2 glues don't stick well. Even JB Weld adhered poorly.
Step 1: Ugly But Functional Repair
The broken off piece is brittle and rotten. Riveting caused it to crack into smaller pieces. I took 2 pieces of roof tin galvanized sheet metal and bent one piece to go up behind the still intact backside of the door handle and a second piece of metal was bent to hold the rotten front piece. JB Weld was used to hold the parts of the front piece together and the two pieces of sheet metal were riveted together.
The assembled patch was tucked up under the backside of the door handle and held in place with JB Weld.
Step 2: Painted to Match
After allowing the epoxy a couple of days to fully cure I spray painted the outside with flat-black car enamel
Because the patch pulls up from behind the handle, it won't pop off. I didn't get fancy with smoothing the outside finish because of the rotten state of the part that broke off.