I had one of my first solder joints fail. but then I am a CRAPPY solderer (is solderer even a word?). After I cleaned all the metal parts better, I have not had an issue. And I would think that if vibration was causing the problem, the NGH 38 would shake the joints to bits. As to the 3D printer parts holding up to the heat, I put in 2 flights today, and had no issues with melting parts or overheating of the motor. It was a cool day, about 54 and a breeze, but I think they will be fine.