I have a GOINDI make VMC and am operating it for the past 3 years. Recently the 'Y' axis drive motor got damaged due to water ingress and I changed it with another second hand motor. After installation of this motor 3 couplings( between motor and ball screw) have broken. The machine manufactureres are also clueless as to what the reason could be. I need help very soon. Please guide.

did water get into the ball screw area?

is this the same type and part number motor as the one damaged?

does the machine run for any length of time before breaking the coupling or does it break as soon as you try to move the axis?

what is the size and type of coupling you use?

Dear Vikas,

Even I suspect that there might be some load on the motor coupling due to the Ball Screw jamming.

Try to check the load on the motor. U may also check the jamming of the slide mechanically by disengaging the motor coupling and then pushing the slide manually

Does the coupling break at the start of the move ,end of the move,or while it is moving . Does it break in a feed move or only during rapid moves?

[QUOTE=vikas;4377]I have a GOINDI make VMC and am operating it for the past 3 years. Recently the 'Y' axis drive motor got damaged due to water ingress and I changed it with another second hand motor. After installation of this motor 3 couplings( between motor and ball screw) have broken. The machine manufactureres are also clueless as to what the reason could be. I need help very soon. Please guide.[/QUOT

check the alignment of motor and ball screw, find out whether bearings of the ballscrews are in good condition