Cannot get Z Axis to move to 0

Gamefanatic3D

I am using Firmware 2.02(RTOS) (2018-12-24b1), and I just recently started running into an issue with being unable to get the X-Axis to properly move to 0. I started down this journey when replacing my generic extruders with a BMG.

When I homed the printer and told it to go to Z0.2 it would actually be about 0.05 above the bed. So I figured I needed to rehome. Got it just touching the glass and performed a G92 Z0. Then did my typical G30 S-1 for the BLTouch, updated my config accordingly and restarted the printer.

Homing the printer again, running a Z0.2 and again I am back at being 0.05mm above the bed. So I figured I would manually adjust the BLTouch to the desired height settling on Z2.195.

Now when I move to Z0.2 I'm about as close to 0.2 above the bed as I can measure, but cannot get the bed (X-Axis) to move below Z0.14 unless I remove the Axis limits (M564 S0).

What am I missing here? Seems like I'm fighting some offset the printer is tracking that is 0.15mm in distance.

Veti

@Gamefanatic3D said in Cannot get Z Axis to move to 0:

am using Firmware 2.02(RTOS) (2018-12-24b1),

please update to the latest firmware. but that is not related to your problem.

please post your config, overwrite and homeing scripts

Gamefanatic3D

The only file that has changed recently is the config.g:
homeall_20190417.g
config-override_20190417.g
config_20191129.g

I had been holding off on upgrading until I got things all worked out, but I'll make an effort tonight or tomorrow.

Phaedrux

You can't get below 0.2 because you have your z axis minima set to 0.2

; Axis Limits
M208 X0 Y0 Z0.2 S1 ; Set axis minima
M208 X400 Y400 Z400 S0 ; Set axis maxima

Phaedrux

You're also loading your heightmap in your config.g that isn't recommended because you haven't yet set your z0 position yet at power up. G29 S1 should be moved to your homeall at the end or to your slicer start gcode to load it before the print starts. If you update your firmware you'll actually get a warning about this.

Gamefanatic3D

@Phaedrux
Thank you for the feedback. Not sure why I was able to get it down to 0.14, but that makes sense! I'll check it when I get home and report back.

Thanks for the heightmap tip, I'll make that move.

Gamefanatic3D

I changed the Z limit to 0.05 and everything is working great! It's always the simplest things we overlook. Thank you for your help.

I upgraded to the v2.04 firmware with the new web control. Still getting used to it. I kind of liked the old interface where I could watch my job stats, control most interface items and still watch my web cam at the same time.