Printer-specific

Bambu A1 PETG Stringing Fix

On a Bambu A1, PETG stringing is usually heat, moisture, or a copied profile. Start with a small temperature proof print before chasing every Bambu Studio setting.

Independent third-party notes. Verify firmware, heater, electrical, and vendor-specific work against official documentation for your exact printer.

Start here

Nozzle temperature, filament moisture, or retraction is letting plastic ooze during travel moves.

On a Bambu A1, PETG stringing is usually heat, moisture, or a copied profile. Start with a small temperature proof print before chasing every Bambu Studio setting.

Check first: Print the same small stringing test 5 C cooler after checking for wet-filament popping or rough wisps.
Change only this: Nozzle temperature: -5 C. If the test improves but still strings, tune retraction next.
Verify with: A two-tower stringing or retraction test using the same spool, nozzle, and speed.
Time: 3 min setup
Risk: Low
Needs purchase: No, unless the spool is clearly wet and you cannot dry it.

Visual diagnosis

Match the visible pattern before changing settings.

Looks like this

Fine PETG hairs between separate towers.
Glossy buildup near the nozzle or seam.
Rough popping extrusion if the spool is damp.

Not this

The printer is showing a firmware, heater, or electrical safety warning.
You are copying numbers from a different printer as final values.
Several slicer values have already been changed without a repeatable test.

Look for PETG hairs or glossy strings, not weak walls only.

First test Print the two-tower test 5 C cooler.

Do not do Do not change temperature, retraction, and flow dynamics together.

Before / after

Compare one small test, not a whole print.

Use the same small test before and after the change so the comparison means something.

Illustration by Print Fixes.

Download a quick test

Stringing two-tower test

Compare temperature or retraction changes with the same spool.

File: STL
Typical time: 8-15 min
Dimensions: 70 x 25 x 45 mm overall.
Footprint: 70 x 25 mm
Height: 45 mm

Download STL

What it testsCompare temperature or retraction changes with the same spool.

When to use itUse when the same symptom repeats and you need a small proof print.

Keep unchanged

Material
Nozzle
Bed surface
All slicer values except the one variable being tested

Expected good resultThe symptom improves on the same test without creating a new failure.

Failure result meaningIf the result does not change, stop tuning that variable and switch branch.

Slicer notes

Keep the same spool, nozzle, and cooling.
Do not change flow while testing temperature or retraction.
Use the same travel and wall speed for before/after prints.

Still not matching?

Jump to the next likely diagnosis

Problem Pattern

The A1 prints PETG successfully when the spool is dry and the profile is close, but hairs between travel moves, glossy blobs, or nozzle buildup mean the temperature and moisture check should come before retraction changes.

Likely Causes

PETG spool is damp enough to ooze during travel moves.
Nozzle temperature is higher than this PETG color needs.
Bambu Studio profile was copied from another PETG brand or nozzle.
Flow dynamics or retraction was changed before temperature was proven.

Print Context

Applies to: Bambu A1, PETG, Bambu Studio, textured PEI
Best first move: Run a PETG stringing tower 5 C cooler on the same spool.
Do not start with: Large retraction changes before checking spool dryness.

Recommended Checks

0/4 done

Check for popping, rough extrusion, or glossy wisps that point to wet PETG.
Print the stringing two-tower test with the current A1 PETG profile.
Drop nozzle temperature by 5 C and repeat the same tower before changing retraction.
If heat helps but does not solve it, tune retraction or flow dynamics one change at a time.

Start with the first check. Keep this page open while you test. The checklist saves on this browser so you can come back after the print finishes.

Verification

The same tower has fewer hairs without weak matte walls.
Nozzle buildup is lower after the temperature step.
A normal PETG part has cleaner travel gaps without layer-bonding loss.

After the test

Use the result, do not keep changing random settings.

If one check clearly changes the print, repeat that exact test once before moving on. If nothing changes, switch diagnosis instead of stacking more slicer edits.

Try next diagnosis Open full checklist

Warnings

Do not use extreme retraction to hide wet PETG.
Check build-plate release guidance because PETG can grip some surfaces too strongly.
Do not compare two different PETG spools as the same test.

Useful when

A print that clearly shows stringing, especially if the same failure repeats.
You want one next move instead of five profile edits.

Skip if

The printer is showing a firmware, heater, or electrical safety warning.
You are copying numbers from a different printer as final values.

More traps to avoid

Changing several slicer settings at once and losing the actual cause.
Ignoring filament condition or bed cleanliness while tuning advanced values.
Keeping one global profile for different materials, brands, colors, and nozzle sizes.

Bench Note

Print-failure log to keep beside the printer

Page: 3D Print Stringing Fix
Printer / firmware:
Slicer profile:
Filament brand and material:
Nozzle size:
Bed surface:
Recent changes:
First check run:
One change tested:
Result:

FAQ

Should I tune retraction first?

Only after a quick temperature and moisture check. Many stringing cases improve with a 5 C temperature step before retraction changes.

Does PETG always string?

PETG is more prone to wisps than PLA, but a dry spool, sane temperature, and printer-specific retraction should make it manageable.

When should I buy a filament dryer?

Buy or use a dryer when the spool pops, hisses, feels brittle, or leaves rough fuzzy strings after a temperature test.

Sources

Prusa: Stringing and oozing Accessed 2026-05-20 OrcaSlicer calibration wiki Accessed 2026-05-20