A multi-colour model, start to finish.
Seven steps, in the order you actually do them, with the thing that usually goes wrong at each one.
The order below is an example, not a rule.
import → repair → paint → split → separate → painted 3MF → slicer
One route through it — Split, Separate and Hollow are siblings, and you reach for whichever the model needs.
The job, end to end.
Seven steps · the snag at each one in the margin
- Open the model
Drag the file onto the window. It is read, its duplicate vertices are merged so it has real topology, and it is inspected — holes, flipped faces, loose fragments, whether it is watertight — before anything is repaired.
A model downloaded from a sharing site is very often none of those things, and the usual failure is finding out at the slicer. The report tells you on arrival, next to what repair then fixed. - Read the report
It stays on screen. It is a panel, not a message that disappears: "three holes, closed" is worth reading twice and worth still being there in ten minutes.
If a model was already clean it passes through untouched and the report says so. Nothing is changed silently just because a repair step exists. - Segment first
Split the surface at its own creases into regions, merge and split those regions until they match the parts you think of the model as having, and assign filaments to all of them in one action.
Painting a whole model with a brush is the slow way to do a job the geometry can mostly do for you. Start here and brush the corrections. - Paint the rest
Brush on the surface, mirror it across an axis for a symmetric model, paint through a thin wall onto the face behind it, or fill everything between two heights with a live preview before committing. There are sixteen slots, and a slot is what the slicer consumes — colour is only how it is shown to you.
One stroke is one step of undo, not one pointer event, so taking a stroke back does what you meant. - Fit the plate
Cut it with a plane and add keys so the halves register when you glue them — if the cut face is too small for the key you chose, you still get both halves, without keys and with the reason. Or separate a painted model into one closed solid per colour: two colours are cut on your paint, and where that cannot be done exactly the model is divided on a grid and the panel tells you what you gave up. Hollow it if you want the filament back.
Parts that do not fit one plate are batched across plates for you and written as the files your slicer expects, rather than as a pile you have to arrange. - Export and slice
Pick the dialect for the slicer you use — the panel names who opens each one. PrusaSlicer 2.9.6, OrcaSlicer V2.4.2 and Bambu Studio V02.08.02.61 all slice our exports with the paint verified all the way into G-code, each through its command-line tool; nobody has yet opened one in Bambu Studio’s own window.
Other slicers are at different stages, and the docs page says exactly which. Do not assume a file that opens has kept its paint; that is the failure this project measures against. - Save the project
A project file is not an export. It keeps the meshes, the paint, the parts and a readable record of what you did. It is written beside your file, verified by being read back, and only then renamed into place, keeping one backup. Your existing file is never touched until a verified replacement exists.
Autosave runs on its own. If something dies, the next launch offers to restore — and only into an empty document, so it cannot land on top of work you have already started.
When it cannot do the exact thing, it says so.
Split keys the cut where a key fits, and otherwise makes the cut without keys and hands back the reason.
Separate cuts on your paint where it can, and where it cannot it divides the model on a grid and names in the panel what you gave up.
A message that reaches you carries what to do next. Every model in the corpus either works or is refused that way, and a refusal with nothing to do next fails the run.
Two things still fail outright.
A key across a colour seam.
Nothing can honour a key across a colour boundary, and the Separate tool has no keys control to offer you. Cut with a plane and key that, then separate.
Separating a model nobody painted.
There is no boundary to cut on. Segment it and assign filaments in one action, or brush two colours on, and ask again.
Try it on your own model.
Nothing is uploaded, and nothing about your model leaves your machine. If it does not do what you need, the limitations page probably already says so.