Basic Information:
Printer Model: Homemade
MCU / Printerboard: octopus max
Host / SBC raspi
klippy.log
Fill out above information and in all cases attach your klippy.log file (use zip to compress it, if too big). Pasting your printer.cfg is not needed
Be sure to check our “Knowledge Base” Category first. Most relevant items, e.g. error messages, are covered there
Describe your issue:
Not a newbie with klipper but somewhat familiar. I have built a second printer larger than first and have a raising bed on 4 nema 17 steppers. Set up quad gantry level to level the bed. It is working somewhat. The question I have is on the stepper movement during the leveling process. The first pass it is usually off at least 5mm and goes to second pass which is usually a little better. When the steppers raise the bed for the first pass they do not move all the same time and I can see the bed warping some. Shouldn’t all four move together. After numerous passes it usually does pass within .5mm. sometimes it fails saying tolerance is increasing.
Is this common for the steppers to move differently while raising for the level?
During other z movements they seem to move in unison.
Has anybody seen this on gantry level?
…
For this we really need the klippy.log. Please attach it to your next post.
Ok here it is.
klippy.log (403.0 KB)
The main question is are the steppers supposed to move out of sync during the level move?
I can see the bed twisting on the upwards move.
As for my understanding, as far you do not have non standard stepper motors, different wiring, left turning lead screws, the dir_pin should all have the same logic (lines 3, 17, 24, 31):
[stepper_z]
step_pin = PE1
dir_pin = !PE0
enable_pin = !PE2
microsteps = 64
rotation_distance = 40
endstop_pin = probe:z_virtual_endstop
position_max = 435
position_min = -3
homing_speed = 30
homing_retract_dist = 10.0
homing_retract_speed = 30
second_homing_speed = 10
[stepper_z1]
step_pin = PB8
dir_pin = PB9
enable_pin = !PB7
microsteps = 64
rotation_distance = 40
[stepper_z2]
step_pin = PG15
dir_pin = !PB3
enable_pin = !PD5
microsteps = 64
rotation_distance = 40
[stepper_z3]
step_pin = PD3
dir_pin = PD2
enable_pin = !PD4
microsteps = 64
rotation_distance = 40
BTW: Do not use hold_current. It’s not recommended any more. Also, the value is way to low in compariosn to run_current.
The steppers are pointed in on four corners so two have to turn opposite directions. They work fine normally I just don’t know if they are supposed to move out of sync during the quad gantry level.
AFAIK as supposed by the name, the gantry level is for gantry, and it does mirrored moves as opposed to ztilt.
You probably want to use Z Tilt for the heating bed.
Afaik QGL is supposed to bend Voron gantry. So, maybe moving the steppers one by one is supposed behaviour here.
Well I guess there is a big dumbass in this house. Been playing with this problem for days now. I guess I should have checked the motor pulleys. Found two of the Z steppers pulleys loose. 
It’s been my fault this whole time.
My bas.
Thanks anyway.
2 Likes