⚠ Don't forget to star the repository if you think the application is useful. This will help others finding it as well.
Changes retraction distance and speed from a specific layer gradually, because Cura is unable to do so. The goal is to save material during stringing tets by doing only a single test. Can be used on GCODE, G-Code, gcode files generated by Cura.
- 4.6.1
- 4.8.0
The STL file I've used for the custom script: https://www.thingiverse.com/thing:2450004
Tested only on Ender 3 and the Cura versions above with my own understanding of gcode syntax.
Make sure you calibrate your extruder by following one of these tutorials!
https://www.youtube.com/watch?v=xzQjtWhg9VE
https://www.youtube.com/watch?v=3yIebnVjADM
Changing retraction distance, starting with 0 with and defaulting to an increase of 1.0mm in every 25 layers (bowden tube)
python ./main.py -f GCODE_FILE_NAME -m distance -l 25 -d 0Changing retraction distance with a defined step distance, starting with 0 and increasing by 0.5mm in every 25 layers (direct drive)
python ./main.py -f GCODE_FILE_NAME -m distance -l 25 -d 0 -ds 0.5Changing retraction distance with a defined step distance, starting with 0.2 and increasing by 0.1mm in every 25 layers (direct drive)
python ./main.py -f ./CE3_stringing_0.4_3_all.gcode -m distance -l 25 -d 0.2 -ds 0.1Changing retraction speed from 25mm/s by 5mm/s in every 25 layer (bowden tube). Note: the given values are in mm/min in Gcode, so have to be multiplied by 60.
python ./main.py -f GCODE_FILE_NAME -m speed -l 25 -s 120 -t 60Changing retraction speed from 2mm/s by 1mm/s in every 25 layer (direct drive).
python ./main.py -f GCODE_FILE_NAME -m speed -l 25 -s 120 -t 60Specify the layer height you would like to use for changing the retraction distance in the second parameter. For instance of you use 0.2 layer height setting the value to 25 will result as retraction setting change in every 25 * 0.2 = 5mm
Specify the initial retraction value. To start with no retraction at all, set this to 0.
The modified .gcode file will be named as GCODE_FILE_NAME.gcode.mod. Make sure you compare this with the original.
Also, make sure you're observing the printer all the time during the execution!
I TAKE ABSOLUTELY NO WARRANTY FOR RUINING YOUR PRINTER!
Let's say I want to do a test with the initial retraction distance of 0 and change it on every 5mm. My layer height is 0.2, so I run the following command:
python main.py -f tests/CE3_stringing.gcode -m distance -l 25 -d 0The script will log out every retraction modification, where it was identifiable in the .gcode file.
In my case this was the following:
...
LAYER: 33
RETRACT: 132.03252 changed to 136.03252 with retraction distance 1mm in G1 F2700 E132.03252
at layer 33
RETRACT: 132.66489 changed to 136.66489 with retraction distance 1mm in G1 F2700 E132.66489
at layer 33
LAYER: 34
RETRACT: 133.36921 changed to 137.36921 with retraction distance 1mm in G1 F2700 E133.36921
at layer 34
RETRACT: 134.00157 changed to 138.00157 with retraction distance 1mm in G1 F2700 E134.00157
at layer 34
LAYER: 35
RETRACT: 134.71042 changed to 138.71042 with retraction distance 1mm in G1 F2700 E134.71042
at layer 35
RETRACT: 135.34281 changed to 139.34281 with retraction distance 1mm in G1 F2700 E135.34281
at layer 35
LAYER: 36
...The goal is to change every line that looks like the example below.
These are the lines I've identified as retraction commands in the .gcode
After running the .gcode file in my Ender 3 I realized that the ideal setting is either 2 or 3mm within just 15 minutes!!!
After figuring out the ideal retraction distance you can even change the retraction speed for a given .gcode.
I've configured the initial retraction speed of 25mm/s and added 5mm/s increase in every 25 layer.
python ./main.py -m speed -f tests/CE3_stringing_2mm_at_45mms_original.gcode -l 25 -s 1500 -t 300The results showed that everything above 30mm/s should be fine.
