First post on this forum so I would like to say hello and thanks for a great forum and all the good advice and comments to be found here. Hopefully someone can help me with my problem and please bear with me I am new to the world of CNC.
Have recently brought a Chinese 6040 unit from eBay that worked well for the first week or so, then the X axis has randomly starts tracking left -X when it should be tracking right +X. The first time I noticed this fault I was jogging the head to the right but it tracked left, stopped jogging and retried and it worked in the correct sense. It did this once or twice at random, I checked all the plugs etc then while milling a part it randomly tracked left cutting a grove right out of the part before I could stop it! Switched stepper motor driver with the Y axis but problem still occurred on X axis, having read though this forum and other information I replaced all the wiring to the motors and earth bonded everything. The first time I turned it back on it did it again! When the fault occurs Mach 3 shows the X axis increasing so I assumed it was not a software fault? Any ideas as to what I should try next very gratefully received.