Hi I built a custom 3D printer (900x1200x650) and i wanted to use klipper. Everything works fine except that i have a continuous layershift in positive y-axis direction. I eliminated all hardware problems that could cause this behaviour. I also changed the drivers, to TMC2209 v1.2 cause i read that the driver also can be a problem due to pulse width problems. What can be the reason for this? Please help!
If you are using a Mellow control board, you need to add the line below to each stepper section.
step_pulse_duration: 0.000001
See this issue for a little more information.
Is it really 1.2m in y dimension?
If yes, it’s really huge and 0.8 A for run_current way too less. Even you have two steppers.
How do you mange they run absolutely synchronous?
If they are a bit out of phase you can get layer shifts too.
i´m using a Bigtreetech GTR Board. Do i still have to add the step_pulse_duration ?
Yeah it is 1,2m. What do you mean by “how do i manage they run absolute synchronous” ?
I have two endstops and then added an additional steppermotor on klipper. As long as i don´t loose steps it is completely synchronous ande i made sure i don´t loose steps.
Do you have a belt or a spindle drive?
it is a belt drive on the y-axis
Then 0.8 A is not enough for that huge bed. Even when you have two steppers.
I have a 400mm x 400mm bed and the single stepper runs on 1.35 A
You bed is over six times larger, so it will have quit an amount of weight.
No wonder you are losing steps/have layer shifts.
No, this is exceptional to Mellow boards.
Otherwise I agree with @EddyMI3D: Most likely lost steps either due to too weak torque and / or alignment issues along the axis. I’d consider it quite a achievement to get such a long axis aligned without any binding.
Overall this sounds like a job for a Nema23
