How much damage do you think this caused?
I didn't set the z-stop screw low enough before I homed the steppers.
I think that it wouldn't harm your printer so much.
You probably only have to re-level your bed again.
The Arduino Materia has a very sturdy design, that will not bend easily.
This happened to me also often, before I implemented an auto-bed leveling solution.
What would help is a full-stop emergency button that immediatly stop any axis-movements.
Nothing is hurt I think, the z stepper just gets hot, the extruder should survive this.
Thanks for the feedback, both of you.
You do have an emergency switch, the power switch. If you cut the power during any operation of the "X,Y,Z steppers, all instructions to the switcher stop. It may cause a clog in your extruder, and would have to be cleared, but that would be a small price to pay, rather than possibly damage a motor. The ramps board has a small pushbutton switch on the board ,right side looking in, that will recycle the firm ware. I presume that there are pin outs on the board that would allow one to add a remote push button if throwing the power switch makes one cringe. That pushbutton is duplicated in the firmware on the LCD as "reset", but when the machine is acting up it is almost impossible to dial in "reset", so I just cut the power and it doesn't seem to cause problems. You can test this out by setting the LCD to Rehome after moving the steppers by hand to the far position and cut the switch in mid homing.
Yes there is pin-out for reset on the Arduino Mega. These are connected to the Ramps shields reset button.