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I'm using an Ender 5 with standard PLA and Creality slicer 4.8.2.

How can I deliberately maximise stringing, and if possible get it to be as consistent as possible.

My aim is to have "thousands of hair like threads strung between two rocky pillars".

If possible I'd like to do this in the slicer with PLA, rather than using cotton or some other material after the model has printed.

Aaargh Zombies
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2 Answers2

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  1. Eliminate retraction in slicer.
  2. Print at a higher hot end temperature; something like +10°C higher than recommenced temperature.
  3. Slow down speed hot end moves when not printing.
  4. Maximize hot end movement without printing where you want strings.
Perry Webb
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Slicers will perform a retraction when moving from one solid to another, the value of which is part of the settings. I've not researched if a specific slicer will allow a negative retraction, but if it's possible, it's likely to create adjustable stringing.

If negative retraction is not possible, one can identify the retraction segments in g-code of the print and find/replace those values with extrude rather than retract. My slicer, Simplify3D does not support reversed retraction, but the code is clear when examined with a text editor:

G1 E-4.0000 F2400
G1 Z0.300 F1200
G1 X118.760 Y117.415 F12000
G1 Z0.250 F1200
G1 E0.0000 F2400
G92 E0.0000
G1 X122.415 Y113.760 E0.0972 F900
build g-code removed for clarity
G1 X118.760 Y117.415 E1.5303
G92 E0.0000
G1 E-4.0000 F2400
G1 Z0.300 F1200
G1 X158.280 Y117.216 F12000
G1 Z0.250 F1200
G1 E0.0000 F2400
G92 E0.0000
G1 X162.216 Y113.280 E0.1047 F900
build g-code removed for clarity
G1 X158.280 Y117.216 E1.5902
G92 E0.0000
G1 E-4.0000 F2400
build g-code removed for clarity
G1 E0.0000 F2400
G92 E0.0000
G1 X162.415 Y113.760 E0.0972 F900
build g-code removed for clarity
G1 X158.760 Y117.415 E1.5303
G92 E0.0000
G1 E-4.0000 F2400

All entries beginning with G1 E-4.0000 represent the 4 mm retraction called by the slicer. One could search for just that code and replace it with a positive value. Some experimentation is indicated to accomplish the desired result. The F value is feed rate and presents another value to adjust.

Pursuant to Oscar's comment, I overlooked the lack of movement as a factor. He is correct, such a modification is likely to create a blob. As a possible compensation, a better modification would be to create a custom extrusion code with a reduced flow rate, using the existing code as a reference.

This starts to complicate the process substantially, requiring far more calculations and edits. I suggest that it could yet be accomplished, but would be more easily done so with post processing of the code via Python or similar, with which I am not qualified to address.

fred_dot_u
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  • Inverted retraction (normal extrusion ) is now done stationary, this may cause for a blob, maybe it is better to extrude while moving? Or, not retract at all. – 0scar Aug 16 '22 at 09:59