I saw one of my school's old robots in the storage room and some of the parts were held on by this stuff... It looked kind of like they melted down a white piece of plastic on and under them and shaped it a little and let it harden again. It was pure white and smooth and very hard. They even had a servo mounted with it. Not the way I would mount a servo but it's on there and it ain't commin off lol. If there's something that comes out of a tube and hardens like plastic without shrinking it might be perfect to modify a plastic gripper I have but I have no clue what that stuff is and where to get it. Anybody know what I'm talking about?