[Drakkn]

Originally Posted by toby51 Hi When i jog the machine in the X & Y axis it is perfect.But when i jog the Z axis it just judders,the ballscrew tries to turn but just judders.I have changed the stepper motor,taken the ballscrew out it runs free.so i can't think of anything else it might be. Thanks Mike

Put the stepper from the z axis onto one of the other axis too see if its the motor - to me it sounds like you have an alignment problem