Sensorless homing

[chris]

homeall.g

M98 Phomex.g
M98 Phomey.g
M98 Phomez.g

homey.g

M400 ; wait til stuff stops
M574 X1 Y1 S3 ; use stall guard for endstops
M913 X30 Y30 ; drop motor currents to 30%
M201 X1000 Y1000 ; reduce acceleration on X/Y to stop false triggers
M915 P0:1 S3 R0 F0 H400; both motors because corexy; Sensitivity 4, don’t take action, don’t filter, 400steps/sec
G91 ; set relative
G1 Z5 F1200 S2
G1 S2 Y-350 F4000 ; move forward 250mm, stopping at the endstop
G1 Y10 F1200; move away from end
G1 Z-5 F1200 S2
G90 ; back to absolute positioning
M400 ; wait again
M913 X100 Y100 ; motor currents back to 100%
M201 X3000 Y3000 ; accel back to original
M574 X1 Y1 Z0 S0 ; set endstops back

[chris]

This post is deleted!

[chris]

video of motor issue

[oliof]

increase sensitivity until you get wrong readings from the motor starting, then slowly reduce it again.

[chris]

cheers i am guessing the sensitivity is this line...

M915 P0:1 S3 R0 F0 H400;

[chris]

M915 P0:1 S-5 R0 F0 H400;

even with s-5 motor keeps trying and not triggering

[baird1fa]

I do believe you can go all the way to -63. Speed, and motor current are also a factor when using the stall detection. it took me quite a bit to find the sweet spot where the stall detection wouldn't detect the ball screw but would detect it hitting the nozzle. I have also read that it works better at higher speeds but lower current settings. Best of luck.

[baird1fa]

The issue you might be having is that you are moving quite slowly at 1200mm/min compared to the number of steps you have set to be reliable. I think many corexy system will move 20mm in 1 full rotation of the motor which would be 400 steps with a 0.9degree motor so that might be your issue. Try lowering that number of steps its your H value in the M915. also try moving faster.

[chris]

sorry is a Cartesian cr-10 belt driven

[Phaedrux]

IF sensitivity still isn't getting you to stall detect, decrease current and increase speed.

Also review your H value in M915 as @baird1fa has said. Default values aren't going to work most likely, you will need to tune it.

https://duet3d.dozuki.com/Wiki/Stall_detection_and_sensorless_homing