Kisslicer and klipper

walker
Posts: 7
Joined: 30 Jul 2016, 13:17

Kisslicer and klipper

Post by walker »

I'd like to ask (open) question about kisslicer and klipper FW.
I love kisslicer and also love klipper.
But it is not possible to use preload nad LA at the same time. I've read some posts it is possible but from klipper github:
https://github.com/KevinOConnor/klipper/issues/1423
https://github.com/KevinOConnor/klipper/issues/1172
you shouldn't use kisslicer's preloadVE on Klipper. preloadVE try to pressurized the nozzle by extruding a lot during the start of a print. klipper doesn't like a slicer manipulating the extrusion like that. the best bet is just diasble preloadVE and use Klipper's pressure advance.

I should say, you shouldn't use kisslicer on klipper at all. the reason being kisslicer will generate code that slowdown the print speed during overhang and klipper doesn't like speed transition at all, it will result in a micro pause during the transition and again when it transits from slow to fast.
It is not problem to disable preload (set to 0) but some mistakes on model (changing speeds at overhang) still exists.
Do you have any experiences with this?
Or how to successfully use kisslicer with klipper?
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pjr
Posts: 692
Joined: 05 May 2015, 10:27
Location: Kamnik, Slovenia

Re: Kisslicer and klipper

Post by pjr »

Yeah, it's pretty much the same with PR Marlin. But in that I deduced that the LA algorithm had issues.

Basically (and this is my very simplistic interpretation; I could be wrong, but it makes sense to me), a properly coded LA firmware should handle Preload. Preload is achieved by generating G-code which performs the required task. If the firmware has problems when following the G-code instructions, then the firmware is faulty. LA should be able to handle the additional Preload feed; yes it will add a very small amount to the Preload feed, but if the printer is calibrated for both, it should work out just fine.

Peter
walker
Posts: 7
Joined: 30 Jul 2016, 13:17

Re: Kisslicer and klipper

Post by walker »

thank you for explanation. I was also fighting with slowing down the speed and flow but I've already found the solution (Mat->Flow adjust-Cool ). It was also problem for Klipper. Just now I am not using preload but try to find the best way to use both - preload at kisslicer and pressure advance at klipper.
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pjr
Posts: 692
Joined: 05 May 2015, 10:27
Location: Kamnik, Slovenia

Re: Kisslicer and klipper

Post by pjr »

walker wrote:Just now I am not using preload but try to find the best way to use both - preload at kisslicer and pressure advance at klipper.
Looking at those Github posts, I don't think you will be able to use both. And it always concerns me when I see posts telling you to use S3D rather than a much better (yes, I know, very subjective) slicer.

It is problematic when allowing only the firmware to do LA/PA and it is also problematic when allowing only the slicer to attempt the same. Neither method produces perfect results by themselves and it made sense to me to combine them.

What I found was that the PR Marlin LA was not constrained by the "normal" printing limits and that LA caused the printer to over-extrude (beyond the printer limits) at the start of a path when Preload was turned on. If the LA code was properly constrained, then this would not happen. I would presume that the same is the case for Klipper.

In my case, I was able to get better results when using Preload than with LA, So I now have LA turned off, but I retain printer profiles for using it, so that I can test each new release of the firmware - just in case things have been fixed and it produces better results.

The biggest problem with Preload is corners in the middle of a path. Preload is only in operation at the start and end of paths, whereas LA/PA should be effective throughout the path.

However, I do trust KISS when it comes to overhangs.

Peter
motley
Posts: 6
Joined: 23 Dec 2017, 08:08

Re: Kisslicer and klipper

Post by motley »

Using Kisslicer and klipper on a Voron 1.6 I get the following error message:

Your printer's firmware reported an error. Due to that the ongoing print job will be cancelled. Reported error: Move exceeds maximum extrusion (3.367mm^2 vs 0.640mm^2)

The klipper notes on this are:

max_extrude_cross_section:
# Maximum area (in mm^2) of an extrusion cross section (eg,
# extrusion width multiplied by layer height). This setting prevents
# excessive amounts of extrusion during relatively small XY moves.
# If a move requests an extrusion rate that would exceed this value
# it will cause an error to be returned. The default is: 4.0 *
# nozzle_diameter^2

I have set the PreLoad VE [us] to 0 -does this stop all preload? If not how do I stop Kiss sending this large extruder cross section message?

Using Kisslicer Premium V2 1.6.3

Thanks in advance,

Chris
leleastro
Posts: 8
Joined: 20 Aug 2017, 13:01

Re: Kisslicer and klipper

Post by leleastro »

In printer.cfg you can add in the extruder section
max_extrude_cross_section: 2
max_extrude_only_distance: 100.0
(or to be sure set these parameters as 9999)
motley
Posts: 6
Joined: 23 Dec 2017, 08:08

Re: Kisslicer and klipper

Post by motley »

Thanks for the reply - I will give that a try, other suggestions (voron discord) were to reduce the purge amount say E10 over 50 mm.
motley
Posts: 6
Joined: 23 Dec 2017, 08:08

Re: Kisslicer and klipper

Post by motley »

Thanks to help from leleastro and others on the Voron discord - problem is solved. The purge line has been revised as follows:

G92 E0; Reset extruder
G1 X3 Y3 F6000; move to beginning of purge
G1 Z0.5; lower to 0.5 mm from bed
G1 X53 Y3 E10 F100; purge for 50 mm
G1 X83 Y3 F9000; destring 30 mm fast
;G1 E-<DESTRING> F1500;
;G1 X150 Y150 F12000;
G92 E0; Reset extruder ; set extruder to Zero
G1 E0 F100

The code above is in the "Select new ext and warm" section of the Printer Gcode tab.

Getting to grips with Kisslicer on my Voron 1.6 - even has a serial number :-)
motley
Posts: 6
Joined: 23 Dec 2017, 08:08

Re: Kisslicer and klipper

Post by motley »

Quick update - apparently overriding the max_extrude_cross_section value can (in some circumstances) remove some protection from the system and it maybe be safer to leave that alone and sort out the cause first - ymmv.

I still value the help given and I am very much at the beginning of this journey.
leleastro
Posts: 8
Joined: 20 Aug 2017, 13:01

Re: Kisslicer and klipper

Post by leleastro »

Sure, but if you get the error after 20 hours of job, Klipper will abort the print. So I just hope kisslicer doesn't put strange things in the gcode files :P but I trust.
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