Bambu Lab published Bambu Studio v02.09.01.70 to GitHub to coincide with the November 3, 2026 launch of the H3C, its nine-tool desktop printer. The release adds H3C support. The feature Bambu calls "the most important update," though, is one a single-nozzle machine could not use: the slicer can now assign nozzles of different diameters to different regions of one model and print each region at its own layer height.
That changes how a slicer treats a part. For most of FDM's history, nozzle diameter has belonged to the job, not the geometry. You picked a fine nozzle that resolves detail slowly or a coarse one that lays down volume quickly, and every region of the print lived with that choice. Bambu Studio 2.9.1 lets each region make its own choice.
How the Feature Works
According to the release notes, the user assigns a smaller nozzle to local details and a larger one to the main body. The small nozzle prints features such as text and scales with narrower lines and thinner layers. The large nozzle handles the bulk with wider lines and thicker layers. Each region keeps a layer height suited to its nozzle instead of taking one compromise value for the whole plate.
Bambu's showcase is the Maker Watch from designer DadaLand, which prints the watch face, case and a flexible TPU strap in one job. The example shows the second half of the idea: on the H3C, nozzle size and material can change together. VoxelMatters, covering the printer's launch, gives a typical split: a 0.2 mm nozzle for detail, a 0.4 mm nozzle for bulk, and a 2.85 mm tool for a soft TPU strap.
The practical payoff is that you no longer have to give up print time to get surface resolution, or the other way around. Bambu's own framing is that detail goes to the areas that need it and speed to the areas suited to fast printing, so the rest of the part doesn't have to print at the same slow pace.
Why It's H3C Only, for Now
Bambu states the limitation plainly: the release supports the H3C first, and information about other models will come in official announcements. The release notes send users to Bambu's Wiki for how the feature works, when it applies and its limitations instead of listing them. Anyone planning a project around the feature should read that page before committing to a design.
The hardware requirement makes sense. Per VoxelMatters, the H3C carries nine Swaptek tools that switch in under six seconds, with hardened steel nozzles (HRC 55+) from 0.2 to 0.8 mm. The tools reach 350 C, the chamber reaches 65 C, and Bambu quotes toolhead speeds up to 1,400 mm/s with 25,000 mm/s² acceleration. The printer sells for $2,499 as an AMS Combo with the AMS 3H, which dries filament at up to 85 C. Because every tool has its own hotend, one job can mix nozzle sizes and materials, and the H3C is the only printer this release supports for the feature.
Color Matching Replaces Color Split
The second big change reorganizes Bambu's color tools. The old Color Split function has been folded into the mixed-color page and renamed Color Matching. Color-mixing sublayers are now on by default for H3C 0.4 mm presets at 0.2 mm and 0.24 mm layer heights. Mixed-color filaments no longer count toward the 32-filament project limit, which helps projects that used to hit that ceiling. The release also adds support for the Bambu PLA Palette kit. VoxelMatters notes that the H3C does CMYKW color mixing with that palette.
Smaller Changes From the 2.8.3 and 2.8.4 Betas
Version 2.9.1 also includes the features from the 2.8.3 and 2.8.4 Public Beta releases. They are less dramatic but more widely useful:
- Top-surface monotonic infill: the line path has been optimized to cut down on travel moves.
- Initial Layer Infill Line Width: a new, separate parameter. Bambu's example is 0.55 mm on a 0.4 mm nozzle.
- Archimedean spiral ironing: a new ironing pattern.
- Custom vendors in Filament Manager: users can now add their own filament vendors.
- Illustrated parameter tips: visual explanations of settings, mainly for process parameters in Simple Mode.
None of these would headline a launch event. Still, the first-layer infill width is one people who tune their profiles will notice. The original Initial Layer Line Width setting now applies to the first layer's other lines, including walls, so first-layer infill can be adjusted separately from wall width. Bambu says a moderate increase can help first-layer adhesion.
What It Means for Makers
For H3C owners, mixed nozzle diameter slicing is the reason to update now. It turns the tool changer from a multi-material convenience into a way to spend print time where it counts: fine nozzles and thin layers on the surfaces people look at, coarse nozzles and thick layers on the parts they don't. Assemblies like the Maker Watch, which combine detailed rigid sections with a flexible strap, gain the most.
For everyone else, the headline feature is a preview, not a tool. Bambu has not said which other printers will get it or when. Until the limits on the Wiki are better understood, it is also unclear how freely regions can be mixed within one model. The release notes don't limit the smaller beta-derived changes to the H3C, though, and the travel-reducing top-surface path, the new first-layer parameter and the spiral ironing pattern may be worth the upgrade for owners of other Bambu printers.
The bigger shift is that slicers are starting to treat a print as a set of regions with different needs, not one uniform job. Bambu has shipped the first version of that idea on a $2,499 machine. How fast it reaches cheaper hardware will decide how many makers actually use it.
