I was having issues sensing the first washer during autoleveling because the head wasn’t going down far enough to sense the pad. After a while I figured out a trick. It appears that the expected height of the first washer is calculated based on the Z value for when the head presses against the flush mount limit switch. No surprise there. I think that my limit switch is too high because about 80% of the time I fail autoleveling.
If, when the head is lowering to touch the limit switch, I gently press down on the back corner of the printer to make the head go down a few extra mm then autoleveling works great 100% of the time.
How can I fix it so I don’t have to push on the corner of the bed to get autoleveling to work correctly?
I’ve tried firmware in 3.6.13, 3.2.21, and 2.6.69 to see if that would matter but it doesn’t make a difference.
I’m hoping I don’t have to take my angle grinder to the limit switch but it’s driving me nuts. If I could program the firmware to try an extra mm when autoleveling to get to the washers then that would make this issue go away too.