Never had that one happen....yet.
We taken the door off the tracks a couple times.
Different people too.
Don't forget your vise handle during zrortn
The problem here, is a vise that has a huge amount of open and close room. ("Dapra" 6" - 5 Ton) It could be fine for days.....but then comes the block that crosses the line. Then it's still fine while running all day long. Lots of people leave the handle in just for the time it takes to change parts, then remove it and run. a habbit forms to leave it in when you finish the last part of the day.
If ya don't see it through the morning fog and return all axis......
it makes for a bad start to your day