Hi, I have done a search and found no results, so I'm posting here in the hope someone has some answers to this issue.
I was 90% through a 5.5hour V-Carve and I noticed the tool was machining in places where it missed previously - in other words, the indexing had moved.
Sure enough, the job was ruined because of the now 2mm offset from earlier alignment.
When the job finished, the tool went to a safe point and I could see (and hear) it moving in Y axis, around 2-3 pulses per second!
Nothing was running, nothing had changed, no fluorescent lights had been switched on, no computer activity had been started or running apart from Windows XP SP3 into Mach3.
And yet, something was causing output pulses to be applied to the stepper motor; one axis only.
This is not a new setup; the machine and software have been used many times over the past 6 months and no hardware or software changes had taken place.
But now the machine is unreliable and I'm reluctant to start another 5-6 hour job until I have some cure for this phenomenon.