How to Use Colour Mixing in Bambu Studio

Summary

• Colour mixing in Bambu Studio blends 2-3 filaments optically by alternating ultra-thin layers
• Supported on multi-nozzle printers (X2D, H2C) and single-nozzle printers (with increased filament waste)
• Available in Normal mode (set ratios manually) and Gradient mode (transition between two colours across the print height)
• Best results on near-vertical walls; avoid using on sloped surfaces, top layers, or bottom layers
• Community prints confirm the feature works as intended on multi-nozzle setups

Purpose

Create gradient and blended colour effects on prints without post-processing, by using Bambu Studio’s colour mixing tool to program filament ratio transitions across the model’s height.

Prerequisites

• Bambu Studio v2.5.3 or later (update via the Studio settings panel)
• AMS loaded with 2-3 compatible filament colours (same material type — mixing PLA with PETG is not recommended)
• A multi-nozzle printer (X2D, H2C) for efficient results; single-nozzle works but increases purge waste significantly

Steps

1. Open your model in Bambu Studio and load your filament profiles. Assign your base colours in the Filament panel. The colour mixing tool will only appear if you have 2+ filaments assigned.

2. Select the model and open the Colour Painting tool. Navigate to the Colour Mixing tab (distinct from the Filament Painting tab). This is where you define mixing ratios, not individual layer colours.

3. In Normal mode: set the ratio. Use the colour bar or triangle selector to define the proportion of each filament. A 70/30 split of a warm white and a grey, for example, produces a warm mid-grey that doesn’t exist as a standalone filament. Experiment with small ratio shifts; the optical effect amplifies at print scale.

4. In Gradient mode: define start and end colours. Set a 100% colour A at the base layer and 100% colour B at the target height. Studio interpolates the transition. This works well for base-to-tip gradients on figurines and display pieces.

5. Preview the result in the slice preview before printing. The layer preview shows how the micro-alternation will distribute across the model. Check that no mixing transitions fall on sloped surfaces or overhang areas — the optical blend breaks down on non-vertical geometry.

6. Increase purge settings for single-nozzle printers. If you’re printing on an X1C or P1S (single nozzle), the colour change frequency of mixing requires frequent purges. Increase the purge volume in Flush settings to prevent contamination between transitions. Budget for increased filament waste.

7. First print: use a small test object. A 20mm cube at your intended colours and ratios takes 10-15 minutes and confirms the blend behaves as expected before committing to a longer run.

The Trap

Colour mixing looks best on strictly vertical walls. On overhangs, bridging, or organic curved surfaces, the micro-layering pattern becomes visible rather than blending optically, and the effect reads as banding rather than a smooth colour. If your model has significant non-vertical geometry, limit colour mixing to the vertical sections by using the Filament Painting tool to mask off the rest. Mixing across the entire model regardless of surface orientation is the most common mistake in first attempts.

Cited References

• Bambu Studio v2.5.3 Release Notes — Bambu Wiki
• Bambu Studio Color Mixing Feature Overview — Smith 3D
• r/BambuLab colour mixing thread
• Bambu Lab H2D review — for multi-nozzle context

Photo by Jakub Zerdzicki on Pexels

Source: r/BambuLab

Content created with AI assistance and reviewed for accuracy.