I had some old 4002-fk motors (sealed) that I wanted to move to X-12. For my first one I got the correct end ball that's resized for american arms, also got the x7-euro sized brushes and got the red springs. I assembled everything and the first visit to track it seemed to break the solder put closest to the pinion (to hold the motor to the chassis). It's an older beuf chassis for G12 (used to be used for F wing classes). It also stripped the spur gear. I was using something like 9/38 in 64 pitch. I guess I just assumed my solder job wasn't good. I decided to go with a 8/39 on the next test (make it easier on the motor) and it stripped another spur gear but this time my solder didn't break. I thought the mesh was good and solid but perhaps not. It IS tough to get the motor in the spot AND have the best mesh possible.
All that said I finally bough 10/44 in 72P this past weekend... my only concern is it'll still strip the spur gear. I'm going to try my best to get a good mesh on the gears and have solid solder.
Is there anything that could be wrong that I'm not thinking of? Does the X-12 arm in a 4002-FK known to cause this issue (something with the stronger magnets?). I'm just looking to see if anyone else ran into this as I can't be the first to want to put an X-12 in a 4002-fk can. If not I'll just assume it's my poor solder job and some sort of combination with 64P gears. Just getting expensive at this point
thanks,
Mike