How to Fix 3D Print Stringing: Complete Troubleshooting Guide (2026)

What Is Stringing (And Why Does It Happen)?

You know those thin, wispy threads of plastic stretched between parts of your print? Like a spider went mad on your model? That’s stringing — also called oozing, hairy prints, or cobwebbing. It’s probably the most common 3D printing annoyance, and I ruined my first dozen prints with it before I figured out what was going on.

The cause is simple: when the print head travels from one spot to another without printing, molten filament leaks out of the nozzle. The nozzle is hot, the plastic is liquid, and gravity does the rest. Tiny threads of ooze get dragged across gaps and between features.

Good news: once you understand the five causes, it’s usually a quick fix. I’ve got it down to a science at this point.

The Five Causes of Stringing

Nearly every case of stringing comes down to one (or more) of these:

1. Retraction settings — not enough retraction distance or speed
2. Print temperature — too hot for the filament
3. Travel speed — too slow between locations
4. Wet filament — moisture absorbed from the air
5. Worn or clogged nozzle — partial blockage messing with flow

I’ll go through each one with specific numbers and fixes.

Fix 1: Retraction Settings

Retraction is your main weapon against stringing. The printer pulls the filament back (retracts) before travel moves, creating a tiny vacuum at the nozzle tip that stops ooze. Get this right and most stringing disappears immediately.

Retraction Distance

How far the filament gets pulled back into the hotend. Too little and it still oozes. Too much and you get clogs — I learned that the hard way on my first Bowden setup.

Starting points I’d recommend:

Extruder Type	PLA	PETG	ABS/ASA	TPU
Direct drive	0.5–2.0mm	1.0–3.0mm	1.0–2.5mm	0.5–1.5mm
Bowden tube	4.0–7.0mm	5.0–8.0mm	5.0–7.0mm	Not recommended

How to tune it:

1. Start in the middle of the range above
2. Print a retraction test tower (search “retraction test” on Thingiverse — there are dozens)
3. Still stringing? Bump retraction distance up by 0.5mm
4. Repeat until the strings are gone
5. Gone too far? You’ll see blobs at the start of each extrusion line — back off by 0.25mm

Word of warning: don’t go above 3mm on direct drive or 8mm on Bowden. The filament gets yanked too far back, cools a bit, and jams when pushed forward again. Ask me how I know.

Retraction Speed

How quickly the filament is pulled back. Faster = cleaner break = less ooze.

Speeds that work well for me:

Filament	Retraction Speed
PLA	30–50 mm/s
PETG	40–60 mm/s
ABS/ASA	35–50 mm/s
TPU	20–30 mm/s

Start at 40 mm/s for PLA and go up in 5 mm/s steps if needed. Don’t go above 70 mm/s or you risk stripping the filament in the extruder gear — which is a far worse problem than a few strings.

Fix 2: Print Temperature

Simple relationship here: hotter filament = more fluid = more oozing = more stringing. A lot of beginners (myself included, once upon a time) print hotter than necessary because it gives better layer adhesion. But there’s a sweet spot.

How to find your sweet spot:

1. Print a temperature tower (search “temp tower” on Printables.com)
2. It prints at decreasing temperatures — 230°C at the bottom down to 190°C at the top for PLA
3. Find the level where stringing stops but layers still stick properly
4. Use that temperature going forward

Sweet spots I’ve found through testing:

Filament	Manufacturer Range	Anti-Stringing Sweet Spot
PLA	190–220°C	195–205°C
PLA+	200–230°C	205–215°C
PETG	220–250°C	225–235°C
ABS	220–250°C	230–240°C
ASA	230–260°C	235–245°C
TPU	210–230°C	215–225°C

Don’t go below the manufacturer’s minimum, though. Under-temperature printing gives you weak parts, poor layer adhesion, and extruder grinding. That’s trading one problem for a worse one.

For the full rundown on filament temperatures and properties, see our filament types comparison guide.

Fix 3: Travel Speed

Travel speed is how fast the head moves when it’s NOT printing. Faster travel = less time for plastic to ooze out = less stringing. This one’s dead easy.

What I use:

• Minimum: 120 mm/s (anything slower and you’re asking for trouble)
• Optimal: 150–200 mm/s
• Maximum: depends on your printer’s acceleration — modern machines handle 200+ easily

Any recent printer from Bambu Lab, Creality, or Anycubic handles 200mm/s travel speeds without blinking. Older machines or heavy direct-drive setups might need to stay at 120–150 mm/s to avoid ringing artefacts.

Two more slicer settings to check:

• Combing mode (Cura) / Avoid crossing perimeters (PrusaSlicer) — keeps the nozzle path inside the print, so any ooze happens where you can’t see it. Brilliant feature.
• Z-hop — lifts the nozzle 0.2–0.4mm during travel moves. Can help, can also make things worse. I test with it on and off for each new filament and go with whatever’s cleaner.

Fix 4: Dry Your Filament

This is the one people miss. If your prints were fine last week and now they’re suddenly hairy, it’s almost certainly wet filament. I ignored this advice for months and wasted hours tweaking retraction settings when the real problem was sitting on my shelf absorbing moisture.

Signs your filament is wet:

• Stringing that appeared out of nowhere with the same settings
• Popping or crackling sounds during printing (that’s steam)
• Rough, bubbly surface finish
• Small zits or blobs everywhere
• Visible wisps of steam at the nozzle

How fast does filament go bad?

Nylon and TPU can absorb enough moisture to cause problems within 24 hours. Seriously. PLA and PETG are more forgiving — weeks rather than hours — but they’ll get there eventually if left out in British humidity.

Drying temperatures and times:

Filament	Drying Temp	Time	How Bad It Gets
PLA	45°C	4–6 hours	Low
PETG	55°C	4–6 hours	Moderate
ABS/ASA	60°C	4–6 hours	Low-Moderate
TPU	50°C	6–8 hours	High
Nylon	70°C	8–12 hours	Very High
PC	65°C	6–8 hours	High

How to dry filament:

1. Filament dryer (best option) — the SUNLU FilaDryer S2 is about £40 on Amazon UK and does a proper job. One spool at a time, precise temperature control.
2. Food dehydrator — works well if you’ve got one. Pull the trays out, pop the spool in.
3. Oven — I’d avoid this unless you’ve tested your oven with a thermometer. Most domestic ovens can’t hold below 80°C accurately, and a temperature spike will fuse your spool into a solid lump. I melted a spool of PETG into a hockey puck doing this. Learn from my mistakes.

Prevention:

Store filament in airtight containers or vacuum bags with silica gel packets. Reusable indicating desiccant (orange when dry, green when saturated) costs about £5–10 from Amazon UK and lasts years.

Fix 5: Check Your Nozzle

If you’ve tried everything above and it’s still stringing, your nozzle might be the culprit. A partial clog or worn nozzle causes irregular flow that shows up as stringing, blobs, and under-extrusion.

Signs of a nozzle problem:

• Stringing that doesn’t respond to retraction or temperature changes
• Inconsistent extrusion width (thin bits and thick bits)
• Grinding sounds from the extruder — it’s trying to force filament through a restricted opening
• Print quality getting progressively worse over time

How to fix it:

1. Cold pull — heat the nozzle to print temp, push filament through manually, then drop to 90°C (for PLA) and pull firmly. The cooled plug brings debris out with it. Repeat until the plug comes out clean. Satisfying when it works.
2. Cleaning filament — run eSUN cleaning filament through the hotend at 230°C. It absorbs and carries away residue. About £8 for a coil that lasts ages.
3. Acupuncture needle — 0.3mm needle (for a 0.4mm nozzle) pushed into the hot nozzle tip. Careful not to damage the bore.
4. Just replace it — brass nozzles cost £2–5 each. They’re consumables, like printer ink. Replace every 500–1,000 hours, or sooner if you’re printing abrasive filaments (glow-in-the-dark, carbon fibre, wood-fill all chew through brass).

Filament-Specific Fixes

PLA Stringing

PLA is the easiest to make string-free. If it’s stringing, the fix is almost always simple:

• Drop temperature to 195–200°C
• Retraction: 1–2mm at 40 mm/s (direct drive) or 5–6mm at 45 mm/s (Bowden)
• Travel speed: 150+ mm/s

If PLA is still stringing after that, it’s wet filament. Dry it. Problem solved.

If you’re new to printing and dealing with stringing, check our best 3D printer for beginners guide — some machines handle it better out of the box.

PETG Stringing

PETG is notoriously stringy. I mean notoriously. Even perfectly tuned PETG will leave fine wisps. Don’t drive yourself mad trying to eliminate them completely — it’s the nature of the material.

How to minimise it:

• Print at the lowest temperature that still gives good layer adhesion (usually 225–235°C)
• Retraction: 2–3mm at 50 mm/s (direct drive)
• Turn Z-hop OFF — PETG stringing gets noticeably worse with Z-hop. This caught me out for weeks.
• Drop flow rate by 2–3% (try 97%)
• Accept that fine wisps are normal — a heat gun waved at arm’s length for 2–3 seconds melts them away instantly. Done.

ABS/ASA Stringing

ABS and ASA string for a different reason — the enclosed chamber needed to prevent warping keeps the air hot, which keeps the filament fluid, which promotes ooze. It’s a catch-22.

• Temperature: 230–240°C (lower end of what works)
• Retraction: 1.5–2.5mm at 40 mm/s (direct drive)
• Enable coasting — stops extruding slightly before each travel move, letting residual pressure finish the line
• Accept some stringing as the price of admission for enclosed printing

TPU Stringing

TPU is the toughest filament to make string-free. It’s soft and elastic, so retraction barely works — the filament just stretches instead of pulling back cleanly.

• Minimal retraction — 0.5–1.5mm maximum, any more and you’ll jam
• Slow retraction speed — 20–25 mm/s
• Lower temperature to 215–220°C
• Slow everything down — print at 20–30 mm/s, travel at 100 mm/s
• Direct drive is essential — Bowden tubes cannot reliably retract TPU. If you’re on a Bowden machine, don’t even try.

Slicer Settings Cheat Sheet

Quick reference that works in Cura, PrusaSlicer, and Bambu Studio (names may vary slightly):

Setting	PLA	PETG	ABS/ASA	TPU
Retraction distance (DD)	1.0mm	2.5mm	2.0mm	1.0mm
Retraction distance (Bowden)	5.5mm	6.5mm	6.0mm	N/A
Retraction speed	40 mm/s	50 mm/s	40 mm/s	25 mm/s
Print temp	200°C	230°C	235°C	220°C
Travel speed	150 mm/s	150 mm/s	150 mm/s	100 mm/s
Combing	Within infill	Within infill	Within infill	Within infill
Z-hop	0.2mm	Off	0.2mm	0.2mm
Coasting	Off	Off	0.2mm³	Off

Sometimes Stringing Doesn’t Actually Matter

Be honest with yourself: does the stringing affect the finished product? Minor strings on internal surfaces, infill areas, or bits that’ll be sanded anyway? Not worth spending an hour tuning settings for.

Quick cleanup for mild stringing:

• Heat gun — wave at arm’s length for 2–3 seconds. Strings vanish instantly. Don’t linger or you’ll melt the print itself.
• Lighter — quick pass with a lighter flame. Risky on detailed prints, fine on chunky ones.
• Deburring tool — for thicker strings on flat surfaces
• Tweezers — just pull them off. Sometimes the simplest solution works.

Honestly, spending 30 seconds with a heat gun is often quicker than spending an hour chasing perfect retraction settings for a one-off print. Pick your battles.

Troubleshooting Flowchart

Work through this in order. Change one thing at a time — otherwise you won’t know what fixed it.

1. Is the filament dry? → If you’re not sure, dry it first. Eliminates one variable completely.
2. Is the temperature right? → Print a temp tower. Drop 5°C at a time.
3. Are retraction settings sensible? → Use the table above as your starting point.
4. Is the nozzle clean and not worn? → Cold pull or just replace it (they’re cheap).
5. Is travel speed fast enough? → Bump it to 150+ mm/s.
6. Still stringing? → Enable coasting (0.2mm³), disable Z-hop, set combing to “within infill.”

That sequence, in that order, will fix stringing on any filament. I’ve yet to find a case it doesn’t solve.