You have great luck with that UV plastic stuff. I am still experimenting with it, and with the versions straight from Hong Kong that are 1.20 for the pen with the little UV light. Like you mention else where, roughing up the surface helps, as does filling voids if you can get the UV light to cure it.
I started keeping one in the car, with some sand paper, with a refill. I also find that my purple laser does a better job curing it, and leaving it out in the sun.
I mainly use it to fix my drones as I crash them and break the shells, landing gear, and prop guards. Stuff CA really doesn't help with, but I can keep flying instead of going home early. I also use it to create franken-drones.
