Last updated: October 19, 2026

How to fix stringing on 3D prints

Those cobweb-like hairs between parts of your print are called stringing. They're one of the most common beginner problems, and usually one of the easiest to fix. Work down this list in order and stop when the strings are gone.

What stringing is (and why it happens)

When your printer finishes one part of a layer and moves to another, the nozzle travels through the air. If melted plastic keeps leaking out during that move, it leaves a thin thread behind. Do that hundreds of times and you get a hairy print.

To stop the leak, slicers use retraction: the printer pulls the filament back a tiny bit before the move, so there's less pressure pushing plastic out, then pushes it forward again when it starts printing. Prusa's troubleshooting guide sums up the usual culprits: printing too hot and incorrect retraction settings. We'd add a third: damp filament.

Before you change anything: print a test

Print a small stringing test: usually two or more thin towers a few centimeters apart, so the nozzle has to travel between them on every layer. Search "stringing test" on Printables, MakerWorld or Thingiverse; many take under 20 minutes. Some slicers, like Bambu Studio and OrcaSlicer, also have built-in calibration tests. Print it once now so you have a "before" to compare against, and change one thing at a time.

Step 1: Check your profile

Start by making sure your slicer (the program that prepares your model for printing) is set to your exact printer model and the right filament type. Printing PETG with a PLA profile, or a generic profile on a printer that has its own, is a very common cause of strings. Manufacturer profiles are already tuned, so get back to them before tweaking anything.

Step 2: Dry the filament

Filament slowly absorbs moisture from the air. In the hot nozzle that moisture turns to steam, which pushes extra plastic out and makes it ooze. Signs your spool is damp:

Popping, crackling or hissing sounds while printing
Tiny bubbles, a rough or fuzzy surface
Stringing that suddenly got worse with a spool that's been out for weeks
Filament that snaps easily when you bend it (common with older PLA)

Dry it in a filament dryer, following the dryer's and spool maker's instructions. As a reference, Bambu Lab's drying guide suggests about 50 °C for 8 hours for PLA and about 60 to 65 °C for 8 hours for PETG in a convection oven-type dryer. Afterwards, store spools in a sealed bag or box with desiccant (the little drying packets). Our filament drying guide has temperatures for PLA, PETG and TPU and the safest ways to do it.

Be careful with kitchen ovens. Many overshoot at low settings, and a few degrees too hot can soften the filament and fuse the coils together.

Step 3: Lower the temperature a little

Hotter plastic is runnier, so it leaks more. Look at the temperature range on your spool and try lowering the nozzle temperature by 5 °C, then print your test again. Keep going in 5 °C steps until stringing improves, but stay inside the range on the spool.

Stop if you see weak layers that split apart, rough or patchy walls, or clicking from the extruder (the motor that pushes the filament). Those mean it's now too cold. A temperature tower, a test print that changes temperature every few millimeters, lets you see the best setting in one go. Our temperature tower guide shows how to print and read one.

Step 4: Adjust retraction (small changes only)

Retraction has two main settings:

Retraction distance (or length): how far the filament gets pulled back.
Retraction speed: how fast it gets pulled back.

The right numbers depend on your extruder type:

Extruder type	How to tell	Typical retraction distance
Direct drive	The motor that pushes filament sits on the moving print head	Roughly 0.5 to 2 mm
Bowden	The motor is on the frame and filament runs through a long tube to the head	Roughly 3 to 7 mm

These are rough ranges, not targets. Your printer's default is the best starting point. Prusa, for example, says its MK3-family printers should use a maximum of 2 mm, while its Bowden-style MINI uses a longer default of 3.2 mm. Change the distance in small steps (about 0.2 mm on direct drive, 0.5 mm on Bowden) and re-print your test.

More isn't always better. Too much retraction can cause gaps at the start of lines, grinding, or even clogs, because softened plastic gets pulled up into the cooler part of the hotend. Use the smallest setting that gives clean results.

Where to find it: in PrusaSlicer it's under Printer Settings, Extruder. In Cura it's under Travel. In Bambu Studio and OrcaSlicer it's in the printer settings, and filament profiles can override it for one material.

Step 5: Reduce travel over open air

Fewer moves across empty space means fewer chances to string. Look for these slicer settings (names vary):

Avoid crossing walls / perimeters: routes travel moves inside the print where possible.
Combing (Cura): keeps travel inside the model's outline.
Wipe while retracting: moves the nozzle slightly as it retracts to wipe off the drip.

Printing multiple objects closer together, or one at a time, also cuts long travel moves.

Step 6: Clean the nozzle

A crusty buildup of old plastic on the outside of the nozzle can drag strings and blobs across your print. With the nozzle hot, carefully wipe it with a brass brush, following your printer's maintenance guide. Prusa notes this is common after long stretches of PETG.

Cleaning up strings you already have

Fine strings peel or brush off. For the rest, a quick pass with a heat gun or hot air tool shrinks them away; keep it moving so you don't soften the print. Small flush cutters or a hobby knife handle thicker strings.

Quick reference

What you see	Most likely cause	Try
Strings plus popping sounds	Damp filament	Dry the spool
Lots of fine strings everywhere	Too hot	Lower the temperature 5 °C at a time
Thick strings and blobs at the start of lines	Retraction too short or slow	Increase retraction a little
Gaps at the start of lines, clicking	Too much retraction	Reduce retraction
Strings only with PETG	Normal for PETG	Dry, slightly cooler, PETG profile

Your next step

Strings gone? Learn the difference between your two most common materials in PLA vs PETG for beginners. If your prints are also lifting at the corners, read why your print corners lift. Did lowering the temperature leave gaps or thin walls? See how to fix under-extrusion.

Frequently asked questions

What causes stringing in 3D printing?

Melted plastic leaking out of the nozzle while it travels between two parts of the print. The usual causes are a nozzle temperature that is too high, damp filament, and retraction settings that do not suit your printer.

What retraction distance should I use?

Start with your printer's default profile. As a rough guide, direct drive printers usually use somewhere around 0.5 to 2 mm and Bowden-tube printers around 3 to 7 mm. Prusa, for example, says its MK3-family printers should use no more than 2 mm.

Does wet filament cause stringing?

Yes. Moisture in the filament turns to steam in the hot nozzle, which makes the plastic ooze and often causes popping sounds, bubbles and rough surfaces. Drying the spool often fixes stringing on its own.

Why does PETG string more than PLA?

PETG is runnier and stickier when hot and absorbs moisture more readily. A few degrees lower temperature, a dry spool and your slicer's PETG profile usually bring it under control.

Is a little stringing normal?

Yes. Very fine, cobweb-like wisps are common, especially with PETG, and they brush or peel off easily. It is only worth tuning if strings are thick, frequent or spoil the surface.