Pressure advance script for dual extruder ?



  • Is there such a thing as a pressure advance calibration script for a dual extruder system ?

    I currently use a single extruder script and I tried to tweak it to work for the second extruder but I am obviously not a python guy because the result isn't pretty (and doesn't work)

    Has anyone built something that could be directly called from DWC rather than using a python script that needs to be hand configured to generate a gcode file, load that gcode file via DWC and then running it ?
    I find that I forget the details of what I need to do to the python script to tweak it for different conditions such as nozzle size, layer height, nozzle temperature, bed temperature etc etc etc.

    It would be fantastic if we could have some sort of macro that we could call that allows entering all the pertinent values and then directly runs the calibration print.
    Anything to make calibrating pressure advance simple would help a lot.



  • @jens55, does the "simplest Method Possible" work for you? It doesn't require any script.

    https://duet3d.dozuki.com/Wiki/Pressure_advance



  • Not really. I am hoping for something that is 'idiot/Jens proof'. Something simple that involves the least possible amount of interaction with the electronics. Something that you press the button and look at the result and stick that into config.sys (editing config.sys should be the only editing required)

    I did get my python script going with enough editing to work. Turns out that PETG is very bad for determining the PA value and I thought that something was broken. Turns out that unlike PLA which is rather obvious, PETG changes extremely gradual and is more than twice the amount of PA compared to PLA filament. I saw no change because I was looking at a completely wrong range of PA.
    I did tests from 0.2 to 1.2 - no discernible difference. I did tests from 1.0 to 2.0 and saw some change. I decided to use a PA value of 2.0 which seems crazy (1.75mm filament, petg, 240C, 0.1 mm layer height, 0.4 mm nozzle).
    Going to a 240C nozzle and 0.2 mm layer height gave me a PA value of 1.45. Dropping temperature to 220 with a 0.2 mm layer height brought the PA back to around 2. Crazy stuff and as I said, a very gradual change.

    My feed tube is somewhere between 800 and 900 mm .... hence the high values.


Log in to reply