I’m converting a Filament Innovations Poseidon from Duet3D to Klipper. The machine has closed loop external X and dual Y steppers, each with their own endstop. X stepper works perfectly, and the dual Y steppers both buzz fine. I also checked the wiring multiple times and everything is identical.
When I go to home the Y axis, the left stepper, [stepper_y] begins to move immediately, but the right stepper, [stepper_y1] delays for about a second before it starts to move, twisting the gantry an unacceptable amount. Does anyone know why this would be and what can be done to fix it?
I tried swapping them and I’m still having the same issue, so I guess something is probably wrong with my wiring for the stepper driver or something is bad with the stepper driver itself.
[stepper_y] is bigger than [stepper_y1] because it includes all the homing and positional data. Just like my Voron 2.4r2 where [stepper_z] is bigger than all of the other Z steppers because it includes the baseline data that the printer needs for that axis.
If you look through it all of the stepper specific things are in both of them.
Filament Innovations is a small company in Pennsylvania that makes large format printers. The Poseidon is a 1m cubed high flow printer that we’ve modified at my work to have a standard .4mm nozzle. The guts of the printer are really good with high end ball screws and linear rails but the Duet3D firmware drove us crazy with the way it worked. We also run Klipper on some other machines so we’re familiar with the firmware already and decided to change it over using two Octopus Pros, 5160’s for the Z steppers and extruder and existing closed loop steppers for X and Y. While changeover has been pretty intense with a lot of new wiring and dealing with the firmware, we’ve gotten everything working except for this one last part.
Also just realized the confusion with my swapping the drivers statement.
We have breakout boards that go to the external stepper drivers, then those go to the steppers. I swapped the breakout board wiring, but not the external stepper wiring because thats a lot more involved. So when I switched just the breakout boards the issue still persisted, which is why I think its an issue with the external stepper drivers.
It persists when I swap the breakout boards on the Octopus Pro, which is why I feel like its something with the external stepper drivers. I have not swapped the stepper drivers yet as thats a lot more work, but I’ll give it a try.
I just swapped the wiring between the external stepper drivers and the steppers and the problem stayed with the one external stepper driver, with the opposite motor now delaying. So its definitely something with the external stepper driver, but the only thing you can really check, the jumpers, are all the same on every external driver.
Can I ask why the steppers for “Y” and “Z” are (physically) larger than “Y1” and “Z1” and so on? There’s no When I look at your klippy.log you send the same current values to the “Z” stepper (which has a TMC5160) as “Z1”, etc. I’d like to understand why defining the end stop sensor to those steppers requires them to be different from the other steppers.
I’m also curious as to why you use TMC5160s for the extruder and Z axis steppers but not for the X and Y axis ones?
In the beginning of my Y steppers and Z steppers I need to specify the dimensions, homing speed, etc. Things that are the same for all of the Y or Z steppers and so only need to be specified once. In fact, if you specify it more than one Klipper will throw an error.
We’re running the X and Y off the external steppers because thats what was used when this printer was running Duet, and the steppers are closed loop steppers. The external stepper drivers process the closed loop aspect so if we want to retain that ability, which we do, we need to use the external drivers.
I’m not sure of the documentation aspects but from experience, I thought that may be the issue at first and I put the extra lines in the [stepper_y1]. Klipper actually threw an error for the lines saying they weren’t needed for the second stepper.
Yeah. We’re actually running a Dyze Design hotend and extruder on it and dont have the high flow options. We wanted a .4mm nozzle for fine details for what we do, so we are willing to sacrifice time to get that detail. It does make the printer a bit weird looking though with this massive hotend mounting plate and this tiny little hotend at the bottom of it.
So potentially weirder things happening.
The Y axis has two steppers which is where having that delay is so bad since it skews the gantry by a lot. The X axis is a single stepper.
I swapped the delayed stepper to the X axis, and the Y axis is now running off the external stepper driver that was good originally and what was the X axis. Now the X axis has the delay in homing.
The weird thing is, once I home the X axis and have that delay, there is no more delay when I simply do movements. Its as if the stepper driver delays powering up then is fine once its powered.
So for now this “solution” works for us, but still is pretty confusing.