Installing BLTouch on Ender 3 with SKR Mini E3 v2 motherboard, flash the firmware and do the first autohome, X and Y-axis autohome to the endstops just fine, but then the print head moves to the position it wants to be in to start the Z-axis homing, and it tries to move past the opposite end of the X-axis and starts grinding.

It grinds for a second or two then stops and begins the Z-axis homing with the BLTouch, but I haven't completed the Z-homing to see if that works yet as I quickly shut down the printer when grinding starts so that it won't damage anything.

I tried changing print bed size in firmware and print margins, but that didn't help, I also thought it might be due to the "z-safe-homing" option being enabled in the firmware but when I disabled that I got an error when I tried to compile it saying that it needs to be enabled when using the BLTouch.

I've been trying to sort this for a few weeks now and haven't had any luck so I thought I'd reach out.

  • $\begingroup$ Please post a link to your configuration.h file. $\endgroup$
    – 0scar
    Apr 11 at 4:28
  • $\begingroup$ dropbox.com/s/z6hix30bpice9dz/Configuration.h?dl=0 $\endgroup$
    – Drethapid
    Apr 11 at 12:14
  • $\begingroup$ Are you using the Z-endstop or the complete Z-probe header of the E3 Mini V2.0? Note that there are some differences with the default Ender 3 config profile. $\endgroup$
    – 0scar
    Apr 11 at 17:49
  • $\begingroup$ complete z-probe header, bltouch is plugged into bltouch slot in motherboard, z-stop is removed (nothing plugged into z-stop slot) $\endgroup$
    – Drethapid
    Apr 12 at 5:02

1 Answer 1


Recently, ran into the same issue on Ender 3 V2 after flashing Klipper. Default Marlin had no issues but klipper was grinding the Y axis after every print when it goes to Y235... it could only go to Y230

After a lot of digging it turned out that Ender end-switch is 5mm off before the actual physical end.

End up fixing it with the following settings in printer.cfg

step_pin: PB8
dir_pin: PB7
enable_pin: !PC3
microsteps: 16
rotation_distance: 40
endstop_pin: ^PA6
position_endstop: 5 #End-stop is not at 0
position_max: 235 #If endstop is 0 235 will grind
position_min: 5 #Prevents moving to 0 and griding in this direction
homing_speed: 20

Don't know what the equivalent for Marlin is. Good luck.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .