Thin strands of plastic between separate areas of the part, or little hairs on the surface.
It happens on any FDM printer. Setting names are Bambu Studio's: in Orca Slicer almost all have the same name, and PrusaSlicer or Cura usually have an equivalent.
Where do I start?
Two questions to sort out what to check. It's a guide, not a sure fix: every printer and every filament is different.
Check in this order
- The printerIf it printed fine yesterday and not today, it's almost never the profile. Check the plate, the nozzle and the room: printing at 15 °C is not the same as at 30 °C.
- The filamentA spool that has soaked up moisture gives strings, bubbles and brittle parts. Dry it before changing settings, and pick that filament's profile in the program.Filament pages
- The quick checksThe “First” list below: it's the fastest to check.Go to “First”
- The slicerOnly now, the settings below, in order. Change one thing, print a small test and compare. If you change three at once and it gets fixed, you won't know which one did it.Go to the settings
Check in this order
- The quick checksThe “First” list below: it's the fastest to check.Go to “First”
- The filamentA spool that has soaked up moisture gives strings, bubbles and brittle parts. Dry it before changing settings, and pick that filament's profile in the program.Filament pages
- The testsCalibrate your filament with these tests:5Retraction1Temperature
- The slicerOnly now, the settings below, in order. Change one thing, print a small test and compare. If you change three at once and it gets fixed, you won't know which one did it.Go to the settings
Check in this order
- The quick checksThe “First” list below: it's the fastest to check.Go to “First”
- The previewStep through the slicer preview layer by layer: that's where you spot missing supports and odd areas in this part.
- The slicerOnly now, the settings below, in order. Change one thing, print a small test and compare. If you change three at once and it gets fixed, you won't know which one did it.Go to the settings
First
- If they showed up suddenly, it's almost always moisture: dry the filament. Raising retraction to cover up moisture doesn't fix it.
- Retraction is in Printer › Extruder › Retraction and is calibrated with Calibration › Retraction test. More retraction isn't always better.
Then, in the slicer (in this order)
- Nozzle temperatureFilament › FilamentA cooler nozzle oozes less. Lower it 5 °C at a time, or find the right one with the temperature tower.
- Avoid crossing wallsProcess › QualityThe nozzle goes around inside the part instead of crossing through the air. Helps with PETG, TPU and parts with many separate areas.
Fixed by calibrating:5Retraction1Temperature
Tried everything and it's still the same? Calibrate your filament with the 8 tests, or write to us with a photo.