MK4S Incorrect Pressure Advance  

MK4S Incorrect Pressure Advance

Hello,

I realized that on the new Firmware PRUSA has changed the old Linear Advance technique with a new Pressure Advance (like Klipper calls it)

So the old M900 command has been deprecated, and on the new GCODE there are only M572 (Pressure Advance).

However, I noticed that I did not get good print after the MK4S HF upgrade, and I looked at the Pressure advance values on the stock profiles.

As example, for PRUSAMENT PLA @MK4S HF (nozzle 0.4) there is a value of 0.036

This stock value does not seem good for the new HF MK4S nozzle or the new firmware. So, I performed the Pressure Advance test, and the result was that the default value is incorrect as you can see. In the wide test, the 0.036 has still deformation:

It would be better values around 0.050. So I run the test again with fine values of 0.001 steps:

looking at it, 0.054 seems to be the best value. So I changed the Start-gcode settings in Filament Advanced for PRUSAMENT PLA, and now it is:

M572 S{if nozzle_diameter[0]==0.4}0.054{elsif nozzle_diameter[0]==0.5}0.026{elsif nozzle_diameter[0]==0.6}0.02{elsif nozzle_diameter[0]==0.8}0.015{elsif nozzle_diameter[0]==0.25}0.12{elsif nozzle_diameter[0]==0.3}0.08{else}0{endif} ; Filament gcode

M142 S36 ; set heatbreak target temp

I will change to this, on all my PRUSAMENT PLA filament settings. Then I will have to test on other PRUSAMENT filament types and other brands.

- Did someone else tested this ?

I attach the gcode-tests, for people that wants to try on printer.

Regards