Random X, Y, Z Cleared Locations Solved

I have been having a problem the last couple of weeks where one of my axes resets to zero, randomly, during tool changes. This has been really frustrating, and I’ve probably ruined around $200 in product at one end mill that buried itself all the way through the table. I’m in the middle of a really big PO and today I have been hawkeye’ing the axis locations during tool changes to make sure nothing fishy happens causing me to toss another board.

Just now, while using the vac hose to clean up some chip on the table, I literally saw the X reset to zero, about 6" from it’s actual set location. Exactly when it happened, I had touched the left top rail of the 1F and felt a tiny shock. The vac hoses create a ton of static electricity, so if I’m holding the hose cleaning things up, I have excess static flowing through me, and it released onto the rail, resetting the X axis. Wow. I’m pretty confident this explains what has been happening (I really hope so!) as I do multiple identical jobs for hours at a time and constantly pull the vac hose off to clean up a bit between jobs.

The most interesting thing is that the X reset itself to the correct location after I jogged the machine around a bit. I’m guessing it interacted with the controller for the reset but that stuff is way over my head so I’m just happy that the problem appears to have an actual, physical cause that I can avoid, and look out for, in the future.

I hope this helps someone out. Also, if someone else can explain what’s going on better, and/or correct my assumption, I’m happy to be wrong.

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Well very interesting. Yes the hose can build a large charge during vacuuming. If that charge is dissipated through the rails to ground creating a large voltage spike. During a pause the controller is in a loop during pause waiting for an input from the touch screen. If that voltage spike somehow gets into the usb cable from the monitor it could trigger a response i.e. a zero. Maybe check the routing on your monitor cabling. I don’t know how well the usb cable is shielded.