Printer Nozzle Frequently Crashes into Bed
For the last few months my printer has been crashing into the bed quite frequently. It seems to happen often when I first boot the printer. I'll turn the printer on and send a command to move the nozzle upwards away from the bed but instead it will move down and crash straight into the bed. It also frequently happens immediately following an autolevel. I have customized the auto leveling in the firmware though, as I've discussed here before, so I could have made a mistake there. It also happens mid autolevel sometimes. Earlier today I ran an autolevel, and after probing 3 corners of the bed it went to probe the final corner and crashed. Any ideas why this could be happening? I'm afraid to try out our new glass bed because of these frequent crashes.