Sensorless homing odd behavior

KristianP

Hi

im in the proces of building an small cnc router , am almost rdy to go , but having trouble making sensorless homing work on the X axies , both Y and Z works no problem at all .When hitting home X button most of the times it starts to move in the wrong direction , if i hit it again a few more times it wil home , but only do one homing pass and not 2 as set in homex.g .Have gone over setup many times now and still not sure what im doing wrong config.g homex.g hopefully someone her can spot it and point me in the right direction .

Phaedrux

It sounds like the X axis sensitivity is too high, or motor current too low, and it's detecting a stall prematurely.

Also, there is no reason to do a double tap homing when using stall detection. There is no added precision and the second tap can be problematic because of the short move distance.

; homex.g
; called to home the X axis
;
; generated by RepRapFirmware Configuration Tool v3.3.10 on Sat Feb 26 2022 19:55:18 GMT+0100 (Centraleuropæisk normaltid)
M400             ; Wait for current moves to finish
M913 X50         ; drop motor current to 70%
M566 X1          ; Decrease Jerk mm/min
M400
G91              ; relative positioning
G1 H2 Z2 F900    ; lift Z relative to current position z5
G1 H1 X-855 F900 ; move quic kly to X axis endstop and stop there (first pass)
G1 H2 X5 F900    ; go back a few mm
G1 H1 X-855 F600 ; move slowly to X axis endstop once more (second pass)
G1 H2 Z-2 F900   ; lower Z again z-5
G90              ; absolute positioning
M400
M913 X100        ; return current to 100%
M400

Remove the back off and second pass.

KristianP

Got i working now thanks for the help .