Bl touch time to time doesn't react

felt342

Hi guys,

I have a BL touch set up and running perfectly. But time to time it's just not reacting then homing - maybe 1 of 20. It does deploy probe but then bed coming close it just pushes a pin into BL touch and then hits nozzle until I press emergence stop. Is there a way to prevent bed moving after hitting nozzle?

Firmware 2.05

Thank you in advance!

DIY-O-Sphere

@felt342
I had the same issue. Solved here.
https://forum.duet3d.com/topic/11503/bltouch-randomly-stops-working/4

felt342

Sounds legit! Thanks a lot I will try it and will make hundreds of Z homing to test it out!

DIY-O-Sphere

@felt342
After adjusting i never had an issue.

Phaedrux

@felt342 said in Bl touch time to time doesn't react:

Is there a way to prevent bed moving after hitting nozzle?

Reduce the motor current for homing moves such that the motor still moves reliably, but hopefully will stall as soon as it is blocked rather than try to ram through.

M913 X35 Y35 Z35	; Reduce motor currents for homing
G91			; relative positioning
G1 S2 Z3 F600		; lift Z relative to current position
G1 S1 X-250 Y-250 F4000 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 S2 X5 Y5 F4000	; go back a few mm
G1 S1 X-240 Y-240 F360  ; move slowly to X and Y axis endstops once more (second pass)
G90 			; absolute
G1 X159 Y142 F6000	; move probe to bed center
M558 F600 A1 		; Dive fast once 
G30			; probe Z
M558 F100 A10 		; Slow second dive with more accuracy
G30			; probe z again
G29 S1			; Load heightmap and enable mesh grid compensation
G1 X10 Y10 Z10 F6000	; return head to park position
M913 X100 Y100 Z100	; Return motor currents to normal

felt342

@DIY-O-Sphere

I found hard to screw it in. It sticks out about 0.2mm. I am afraid to break it, is it lock by something?

felt342

@Phaedrux

Thats a smart one!

DIY-O-Sphere

@felt342
It seams they have modified the newer ones.
The picture of the set screw isn't included in the manual anymore.
I have also found a video for the pin replacement on youtube .
So I think yes it is locked.