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PETG Stringing? What to Do & How to Fix It

If PETG is stringing, do not automatically turn the nozzle hotter. First make sure the filament is dry. If it is dry and still strings, a small temperature reduction often reduces ooze as long as you stay within the filament maker's recommended range and layer bonding remains good. Then tune retraction and travel.

Best troubleshooting order: dry the filament first, then verify temperature, then tune retraction and travel. If you change all of them at once, you will not know which change actually fixed the problem.

1. Dry the PETG before tuning retraction

PETG absorbs moisture from the air. Wet filament can increase stringing and oozing even when the slicer settings have not changed.

Use the filament manufacturer's recommended drying temperature and time. Drying first prevents wasting time compensating for moisture with bad slicer settings.

2. Should PETG nozzle temperature go up or down?

If the PETG is dry and stringing continues, test a small temperature reduction rather than automatically increasing heat. Hotter PETG flows easily but can ooze more during travel. Stay within the filament maker's recommended temperature range and make sure layer bonding and extrusion remain good.

3. Tune retraction in small steps

Retraction reduces pressure before travel. The right distance and speed depend on the printer, hotend and whether the extruder is direct drive or Bowden. Too much retraction can create jams, grinding or inconsistent extrusion.

4. Increase travel speed when the machine can handle it

A slow travel move gives molten PETG more time to leak from the nozzle. Faster non-print travel can reduce string formation, but stay within the printer's reliable motion limits.

5. Keep travel moves inside the part when possible

Many slicers have options such as avoiding crossing walls, combing or routing travel over already printed areas. Reducing open-air travel can make strings less visible even before retraction is perfect.

6. Check cooling

Cooling affects how quickly the strand leaving the nozzle firms up. PETG often needs less fan than PLA, so test modest changes rather than assuming maximum fan is best.

7. Check flow and extrusion

If the part also has swollen dimensions, overfilled top surfaces or blobs, verify extrusion and flow. Excess material pressure can worsen PETG oozing.

8. Inspect the nozzle

PETG can build up on the outside of the nozzle and drag strands around the print. Inspect and clean the nozzle according to the printer manufacturer's service guidance.

9. Use a small stringing test

Use a short test model and change one variable at a time. Record nozzle temperature, retraction distance, retraction speed and travel speed so the best result is reproducible.

10. Quick PETG stringing checklist

  1. Dry filament.
  2. Verify nozzle temperature.
  3. Check retraction distance and speed.
  4. Review travel speed.
  5. Reduce open-air travel paths.
  6. Adjust cooling carefully.
  7. Verify flow if blobs or over-extrusion are also present.
  8. Run another small test before changing a second variable.

Why PETG can ooze even when stringing is mild

Oozing can show up as blobs at travel points, seam buildup or a small amount of material leaking while the nozzle moves. That is still usually a pressure and temperature problem, so the same moisture, temperature, retraction and travel checks apply.

Still getting PETG strings or ooze?

Send the printer model, PETG brand, nozzle size, temperature, retraction distance and speed, travel speed, fan settings and photos. LayerForge can help narrow down the cause.

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