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.

import → repair → paint → split → separate → painted 3MF → slicer

Step one · 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.

Step two · Look at what came back

The report 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.

Step three · Segment before you paint

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.

Step four · 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.

Step five · Make it fit the plate

Cut it with a plane and add keys so the halves register when you glue them, or separate a painted model into one closed solid per colour if your printer has no multi-material unit. 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.

Step six · Export and slice

Pick the dialect for the slicer you use — the panel names who opens each one. PrusaSlicer 2.9.6 is the one where the paint is verified all the way into G-code.

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.

Step seven · Save the project, not just the export

A project file keeps the meshes, the paint, the parts and a readable record of what you did. On the desktop it is written beside your file, verified, and only then renamed into place, keeping one backup.

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.

Try it on your own model.

Nothing is uploaded and nothing is installed. If it does not do what you need, the limitations page probably already says so.