Stripping Threads on Gear Box

[Matthew_H]

I would like to ask has any team had the aluminum piece that screws into the drill motor strip its threads. The reason I am asking is that we have gone thru the ones that FIRST shipped and now we have stripped one of the ones that our machine shop made for use to replace the bad one. We have used Locktight in the piece but it seems that as we drive the robot that when we put the motor into reverse that we are back drilling and it trys to unscrew itself. Could we be putting the piece on. Our next step is to JB weld the piece to the drill motor and make it so it cannot come off without breaking the drill motor. Please comment because we are frustrated as we are so close to having a nice driving robot.