Hello I´ve hit a wall building my custom multicolor 3d printer from an Ender 3 max with spare steppers motors from other printers. I have my two MCU working, 5 bowden extruders to a splitter and one hotend, I have pretty all set but I note that pressure advance works only with the (extruder) not with the rest steppers extruders.. Klipper take the T0 as is it was direct drive and the rest as take filament to this extruders, in my setup all works in pararell. I do a lot of search and a lot of chatgpt trying to fix this, but there is no way to tell to klipper that my setup it´s in pararell and put preassure advance at every single extruder. I´m right? If this feature is not avaiable in klipper it can be possible to make avaiable in the future? I was very close to make the printer works with all the extruders working perfectly.. Thank you very much in advance.
Welcome Leomax,
interesting. Can you share photos of your machine?
You could start a pull request @github.com/Klipper3d, but I never did and my impression is you need some supporters to start that PR.
Maybe someone else can help here, who knows the Klipper PR process?
@Leomax
For clarification:
You assume, that PA only works with T0 and not with the other extruders?
If yes, how do you come to that conclusion?
I ran this: Pressure advance - Klipper documentation on both on the extruders on my IDEX machine and put the results into the [extruder] sections.
Thank you for your response, I will take some photos and share. Do you think I better wait for supporters?
Hello Eddy I ran all kind of approach that I and Chatgpt can do. In the first questions chatgpt do some macros to try to enable PA in all the motors, but all are useless. At the end chatgpt say to me there is no way to apply PA to the other extruders because there is two possible configurations in klipper, one hotend, one [extruder] and the other/others extruders are steppers extruders like on any AMS, and the other option is two or more hotend with extruder like prusa and I think your printer. In this case, you can use PA on any extruder, but you can´t use this configuration with one hotend.
Obviously you think ChatGPT is omniscient.
Please attach the klippy.log to your next post so that we can see what we are talking about.
Hi @Leomax ,
You should be able to use a command like:
SET_PRESSURE_ADVANCE EXTRUDER=mmu0 ADVANCE=xxx
I have very little programming skils so chatgpt it´s not perfect, but help me to accomplish the things when I was stuck..
sorry I´m not a programmer..
Eddy this is the klippy.log: klippy.log I cant upload here directly because is more than 10mb. Tank you very much
As the initial and deleted template mentioned, you can shrink it by using ZIP.
Hello! I use orcaslicer and it generate after any filament change: SET_PRESSURE_ADVANCE ADVANCE=0.4; Override pressure advance value and I have to put a macro to avoid “Unable to infer active extruder stepper” error. This is the macro:
[gcode_macro SET_PRESSURE_ADVANCE]
rename_existing: _SET_PRESSURE_ADVANCE
description: PA siempre al extrusor principal
gcode:
{% set adv = params.ADVANCE|float %}
_SET_PRESSURE_ADVANCE ADVANCE={adv} EXTRUDER=extruder
I also try to set PA in the start print macro but no sucess.
How do I can apply your command? SET_PRESSURE_ADVANCE EXTRUDER=mmu0 ADVANCE=xxx I assume that =mmu0 going to be extruder or stepper extruder? Sorry for my litle programming skils. Thank you very much.
klippy.zip (2.3 MB) Here is thank you!
Here are the photos, don´t look the mess it´s a work in progress, but promising form the moment. I will put a shelf on top to put the spools in the future and a nozle clean and waste can in the left side attached to x gantry.
For the electronics it´s a pi zero 2w with two mcu, main is a SKR mini V2 and the seccond one, it´s a Creality 1.1.4 board 8bit it only take care of the 4 extra extruders.
I belive what you can do is to disable the pressure advance in Orca Slicer (in filament settings) so that Orca Slicer doesn’t generate SET_PRESSURE_ADVANCE commands and then enter the pressure advance parameters in your printer.cfg for each extruder separately. And also get rid of the macro where you override the pressure advance command.
I will try and post results! Thank you very much!
That´s the key!! Thank you very much!! I must to do further test, but i ran a small print and the T1 seems to apply pressure advance with SET_PRESSURE_ADVANCE in extruder, and all the stepper extruders. I think is not the perfect solution because with different materials, pressure advance will change, but it´s better than not having PA at all. You save me!!
I looked into Orca Slicer’s code and it really doesn’t take the extruder number into account. Maybe a PR can be made on this 
Can you explain what is a PR? Sorry for my limited technical vocabulary. My english it´s no so good. Thank you in advance. By the way, all the extrudrers work with PA perfectly, I ran more extensive test this morning!