A 3dsplitter alternative: cutting by color, with snap-fit joints
Looking to replace 3dsplitter so you can print a model in several colors? That is a different class of task: the model is cut along its color zones, not with a plane, adds engineered snap-fit joints with clearance tuned to plastic shrinkage, and exports a watertight 3MF. You print each part in its own filament on an ordinary FDM printer — the color comes from the plastic, not from paint or an AMS.
How color cutting differs from plane splitting
3dsplitter and similar online splitters are good at their own job: they cut a model with a plane so a large part fits the bed, and often add alignment pins to keep halves lined up. If the goal is simply to break volume down to print size, that is enough. Color cutting solves a different problem — multicolor printing without a multi-material printer — so it cuts differently:
- Cut line. A plane splitter cuts with a straight plane. A color cut runs along the color-zone boundary, following its shape, so the seam lands where the color changes and all but disappears after assembly.
- Joint. Plane splitters use an alignment pin meant for glue. Glue-free assembly needs a cantilever snap-fit joint with clearance computed for FDM shrinkage, so parts snap together without glue.
- Color. A plane cut ignores color. With a color cut each part maps to its own filament, so the result is a multicolor model without an AMS and without painting.
- Output. You get a watertight 3MF for Bambu Studio, PrusaSlicer and Cura, with each part already assigned to its color.
If you only need to break a large model down to fit the bed, a plane splitter is enough; color cutting matters when color and glue-free assembly do. BunnySplit's own cutting editor is in development; today you can order a print from a maker on the marketplace. Its core strength simply lies elsewhere: in color and in the joints that plane splitters do not offer.
How to split a model by color — 3 steps
- Upload your model in the browser. STL, OBJ, GLB/glTF, 3MF and PLY are supported; units are confirmed on import so the scale is correct.
- Set the colors. If the model has color or texture, zones are detected automatically; if it is single-color, you paint zones with a brush or turn on geometry auto-segmentation (necks, waists, joints).
- Download parts with joints. The engine cuts along the zone borders, adds snap-fit joints with clearance tuned to the plastic, and exports a watertight 3MF — print each part in its color and snap it together.
What clearance the engine builds in
Clearance is the gap between the male and female halves of a joint, without which parts either jam or rattle after printing. FDM prints slightly wider than nominal and plastic shrinks as it cools, so the gap is planned in advance. Typical starting values:
- Default fit is snug, 0.30 mm per side; a loose 0.45 mm and a tight 0.18 mm fit are also available.
- On top of the fit, shrinkage compensation is added: PLA shrinks about 0.3%, PETG 0.5%, ABS 0.7%, and the engine folds that fraction into the gap automatically.
- Safety caps keep the added shrinkage from turning the gap into slop, and keep the minimum gap above the FDM printable floor.
More on the cut itself in split an STL by color, on joints in the snap-fit connector generator.