Shrinkage compensation in Bambu Studio for ABS, PETG and PLA

Bambu Lab publishes no shrinkage value for its ABS (acrylonitrile butadiene styrene), and its own filament profiles leave Bambu Studio’s Shrinkage field at 100%, which is off. Start at 99.36%. That corrects the 0.64% X and Y shrinkage a university study measured on printed ABS. Then print a 20 mm cube and correct from what you measure.

Field names and behavior below were checked in the Bambu Studio source for 2.8.2.61 (the current public release, August 2026) and 2.8.4 (public beta, September 2026).

Where is the shrinkage setting in Bambu Studio?

Shrinkage is a filament setting, not a print setting. Click the “···” icon beside the filament, choose Edit, and find Shrinkage under Filament settings > Basic information. Type the cooled size as a percentage of the design: 99.4% if a 100 mm part prints at 99.4 mm. 100% is off.

What the field does, from Bambu Lab’s wiki and the slicer source:

• Per filament. Each filament profile has its own value. A print is scaled by the value of the filament printing its walls.
• X and Y only. The field scales each layer’s outline by 100 divided by the value. Height is untouched, so a Z correction goes in the object’s Scale tool.
• Advanced option. The source marks it as an advanced setting. If you do not see it, switch the settings view to Advanced.
• Limits. The lowest value it accepts is 10%; the default is 100%.
• Spacing. The tooltip warns that scaling happens after the collision checks, so leave extra room between objects on the plate.

Bambu Lab’s wiki says to click the save icon at the top right after typing the value. Save it as your own filament preset with a name you can recognize, such as “ABS black 99.36”.

What shrinkage value should you use for ABS on a Bambu Lab printer?

Start at 99.36% in Bambu Studio’s Shrinkage field. That value corrects the 0.64% average X and Y shrinkage measured on printed ABS parts at Binghamton University. The study used a QIDI printer, not a Bambu Lab one, and Bambu Lab’s ABS data sheet lists no shrinkage, so treat 99.36% as a first guess and measure.

The same study gives starting points for PLA (polylactic acid) and PETG (glycol-modified polyester). Bambu Lab’s PLA Basic and PETG Basic data sheets list no shrinkage either.

Material	Measured X / Y shrinkage	Shrinkage field	Measured Z	Z in the Scale tool
ABS	0.59% / 0.69%	99.36%	grew 0.92%	99.09%
PETG	0.76% / 0.54%	99.35%	shrank 0.73%	100.74%
PLA	0.63% / 0.35%	99.51%	shrank 0.80%	100.81%

Weiser et al. printed three part designs per material on one QIDI X-One2 and measured them with calipers. A different printer, enclosure, fan setting or ABS brand will move these numbers. Your own test print matters more than the starting value.

The Z column is optional. Change Z only if your heights measure wrong. First-layer squish and elephant’s foot (a flared first layer) move Z readings as much as material shrinkage.

How do you find the exact value for your printer?

Print a test cube, measure it and correct the field. Bambu Lab’s wiki gives this procedure:

1. Right-click the plate, choose Add Primitive > Cube, and use the Scale tool to set whole-number sizes such as 20 × 20 × 20 mm. A 100 mm part gives a more precise reading.
2. Print with the filament, temperatures and cooling you use for real parts.
3. Let it cool to room temperature, then measure X and Y with calipers at mid-face.
4. Enter (measured ÷ designed) × 100 in the Shrinkage field.

Bambu Lab’s example cube measured 18.5 mm against 20 mm, so they entered 92.5%. The reprint measured 19.7 mm.

That formula is exact only if the field was at 100% for the test print. If it already held a value, multiply: new value = old value × measured ÷ designed. Correcting after Bambu Lab’s reprint gives 92.5% × 19.7 ÷ 20 = 91.11%. The shrinkage compensation calculator does this arithmetic and also gives the Z scale.

Bambu Lab’s wiki recommends a separate correction per model for tight assembly fits, because different shapes show different errors.

Does shrinkage compensation work on multi-color prints?

Not in the newest beta. In the 2.8.4 source, Bambu Studio skips the shrinkage scale on any color-painted object whose filaments carry a value other than 100%, and shows the warning “Shrinkage compensation does not take effect on color-painted models.” The 2.8.2.61 public release has no such check and scales by the wall filament’s value.

For a multi-color part that must fit, leave every filament at 100% and scale the object with the Scale tool instead. X-Y hole and contour compensation are also switched off on color-painted objects in both versions.

Why are holes still too small after setting shrinkage?

Bambu Lab’s wiki says the Shrinkage field fixes outer dimensions only. Internal features such as holes need their own setting, under Quality > Precision in the print settings:

• X-Y hole compensation grows or shrinks every hole by a fixed distance in mm. Positive values make holes bigger. Raise it in small steps until a pin or bearing fits.
• X-Y contour compensation does the same for outer walls.
• Auto circle contour-hole compensation targets round holes and shafts up to 50 mm. The source tooltip lists support for PLA Basic, PLA CF, PET CF, PETG CF and PETG HF only, so it does not cover ABS. Bambu Lab’s wiki says it is tuned mainly for the H2D.

Calibrate Shrinkage first and holes second, so each correction stays small. The dimensional accuracy calibration guide covers the full order.