Issue with Retraction Tower on Cura 4.8.0 / gcode "G1 EXX" lines?

[5axes]

Issue with Retraction Tower on Cura 4.8.0 / gcode "G1 EXX" lines?

[stephentt]

I did as you said and it looks like the result is better. Thank you for taking a look and responding quickly! I got this as a result for the relevant section:

G91 ;Relative positioning
G1 F2700 E-3.50000
G1 E-2 Z0.2 F2400 ;Retract and raise Z
G1 X5 Y5 F3000 ;Wipe out
G1 Z10 ;Raise Z more
G90 ;Absolute positioning

G1 X0 Y220 ;Present print
M106 S0 ;Turn-off fan
M104 S0 ;Turn-off hotend
M140 S0 ;Turn-off bed

M84 X Y E ;Disable all steppers but Z

[5axes]

I think I still have an issue when the Value of the Change Layer Offset. Anyway with this model the value should be set to 4 .

As in many profiles the first layers are using special settings to manage the fan speed values, it's no recommanded to start from 0 . And the minimal value must be set to 1. I Will modify the script for the next release to a minimal value to 1 for the Change Layet Offset value

[lwiart]

Thanks 5axes! I'll do keep "Change Layer Offset = 4"

In the interim, I tried to generate gcode (Cura 4.8.0) with distance/3/1/38/4, and I still get those weird extrusion values all along the G1s, that go from 0 to 1361. Is that normal?

;LAYER:0
M117 speed (3.0/1.0)
M107
G0 F6000 X125.272 Y136.534 Z0.2
;TYPE:SKIRT
G1 F2700 E0
G1 F1200 X126.013 Y135.959 E0.0312
G1 X126.8 Y135.449 E0.06239
G1 X127.628 Y135.008 E0.09359
G1 X128.49 Y134.639 E0.12478
G1 X128.991 Y134.463 E0.14244
G1 X129.136 Y134.416 E0.14751
G1 X130.04 Y134.165 E0.17871
G1 X130.962 Y133.992 E0.20991
...  
;LAYER:196
M117 speed F480
;TYPE:WALL-OUTER
;MESH:RetractTower
G1 F600 X162.757 Y152.587 E1359.32512
G1 X163.288 Y152.474 E1359.34317
G1 X163.786 Y152.252 E1359.36131
G1 X164.227 Y151.932 E1359.37943
G1 X164.59 Y151.528 E1359.3975
G1 X164.861 Y151.056 E1359.4156
G1 X165.029 Y150.541 E1359.43362
G1 X165.086 Y149.998 E1359.45178
G1 X165.029 Y149.457 E1359.46987
G1 X164.86 Y148.941 E1359.48793

[5axes]

Yes it's normal .. You have two modes to controle the Extruder axis :
The default value are set to absolute mode this is the case in your G-Code .
You can also switch to an incremental value (Relative Extrusion), In this case you should find the retraction value directly in your Gcode.

[5axes]

I see your Error , your configuration of the CR10S is not correct. And a M83 code is missing before your the
G1 E-2 Z0.2 F2400 :

[5axes]

I recommand to use the following code :

M83 ; E Relative
G1 F2400 Z20 E-5 ; Retract and Raise Z

But rectract and Raise the Z on the same line is not a good solution because you are using the same speed for E and Z So you should Change to :

G91 ; Set coordinates to relative
G1 F1800 E-5 ; Retract filament 5 mm to prevent oozing
G1 F3000 Z20 ; Move Z Axis up 20 mm to allow filament ooze freely
G90 ; Set coordinates to absolute

Cura in this case will change the -5 value to the right settings even if you don't specify the M83 instruction

[lwiart]

Thanks for the hints. It's useful for comprehension.
But since I use Cura, when I used your plugin to import a Retraction Tower model, then the "RetractTower" script, the gcode snippets I pasted here are from what is being generated (with "Relative Extrusion=FALSE"), to get the best retraction setting between 3 and 7mm.

So, should what you mention be put in the start gcode for the machine? or should the RetractTower.py script be updated?

[5axes]

These comments are not related to the RetractTower.py script. I think the problem exists more generally on your prints. The changes are related to the configuration of the machine. I am surprised that this problem is not more often encountered for CR10S Pro users

[lwiart]

Sorry for my belated reply. Thanks for the hint!

[5axes]

Whitout news .. don't need to keep it open

[stephentt]

I am also having this issue and I am using the default Ender 3 machine profile in Cura. I am wondering why this isn't happening to everyone who is using your script on a Creality machine? Here is the end gcode as default provided by Cura:

G91 ;Relative positioning
G1 E-2 F2700 ;Retract a bit
G1 E-2 Z0.2 F2400 ;Retract and raise Z
G1 X5 Y5 F3000 ;Wipe out
G1 Z10 ;Raise Z more
G90 ;Absolute positioning

G1 X0 Y{machine_depth} ;Present print
M106 S0 ;Turn-off fan
M104 S0 ;Turn-off hotend
M140 S0 ;Turn-off bed

M84 X Y E ;Disable all steppers but Z

Here is the end gcode after adding your script:

G91 ;Relative positioning
G1 F2700 E1292.14860
G1 E-2 Z0.2 F2400 ;Retract and raise Z
G1 X5 Y5 F3000 ;Wipe out
G1 Z10 ;Raise Z more
G90 ;Absolute positioning

G1 X0 Y220 ;Present print
M106 S0 ;Turn-off fan
M104 S0 ;Turn-off hotend
M140 S0 ;Turn-off bed

M84 X Y E ;Disable all steppers but Z

So like you mentioned above, it is a G91 change to relative followed immediately by an absolute extrude value as modified by your script. So it seems like the best thing would be for the script to leave the start and end gcode unmodified if there is a way to identify it separately from the rest of the gcode?

[5axes]

Ok here it's clear. I need to check if there is a G91 or G90 added by the user or by a previous script.
Thank's a lot for this exemple. Try to fix it in the next version

[5axes]

Modification of the RetractTower Script.

Need to be tested : https://github.com/5axes/Calibration-Shapes/releases/tag/V1.2.6

[stephentt]

Hi there do you need me to test it in my environment and if so do you have any instructions on how to do so? I have only used the plugin from the Cura marketplace before.

[5axes]

Download the curapackage present in the last release on this Github ( the link to this release is in the previous post) . Drag ans drop the file in Cura to install the release. Restart Cura and test the new release . ( don't forget to update the script with the copy script function)

[5axes]

Last release published on the marketplace. Should solved this issue.

[marcoviarengo]

Hi all!
I have a little issue. I run this plugin and I don´t get stringing with 1mm but when I am not running the plugin and I set that value to my retraction it doesn´t work. Is there something else I need to change? I've tried 20 to 40 speed, combing mode off and on.. For sure I am missing something...