Thin hairs between towers or across open spaces. The nozzle drools during travel moves instead of cutting cleanly.
Is This Actually Stringing?
Wipe your finger across the strings. If they pull off cleanly with no surface damage underneath, it’s stringing. If the surface itself is rough or bubbled, the problem is wet filament or over-extrusion — not retraction.
Diagnose Before Adjusting
Print a retraction calibration tower (two narrow pillars, 5–10mm gap). Judge by the space between them — not the tower walls. Strings crossing the gap confirm the issue. Blobs on the tower surface point to a different root cause.
Common misdiagnosis: Increasing retraction when temperature is the real driver. High temps (PETG at 250°C+, PLA at 220°C+) cause oozing that retraction alone can’t fix. Drop temperature first.
Fixes in Priority Order
1. Temperature — try this first
Lower nozzle temperature by 5°C and reprint. PETG strings heavily above 245°C; PLA above 215°C. If strings disappear at a lower temp, you’re done. If they’re still there but thinner, combine with step 2.
2. Retraction distance
Start conservative — going too high causes heat creep in direct drive setups.
- Direct drive: 0.5mm → 1mm → 1.5mm (stop before 2mm)
- Bowden: 3mm → 5mm → 6mm (stop before 7mm)
Increase by one step at a time. If jams start appearing, you’ve gone too far.
3. Travel speed
Raise to 180–200mm/s if your machine supports it. Faster travel gives less time for the melt to droop. On slower machines (Ender 3, Aquila), 120–150mm/s is achievable without skipping.
4. Combing / Avoid Crossing Perimeters
Enable in your slicer. This routes travel moves inside the print rather than across open air, eliminating most remaining strings without changing any temperature or retraction value.
What Not to Do
Don’t set retraction above 2mm on direct drive — it causes jams inside the heatbreak. Don’t chase stringing by raising temperature trying to get “cleaner cuts” — this makes it worse. Don’t enable Wipe on Retract until you’ve confirmed the above settings aren’t already solving it.
Material-Specific Notes
PETG strings more than PLA by design — it’s adhesive, which is also why it sticks well. Expect some fine stringing even with perfect settings; target hair-thin strings you can rub off, not zero strings.
Silk PLA is similar — the additives lower viscosity and increase ooze. Accept slightly more stringing or drop to 195–200°C.