How a two-colour print works
The printer has two materials loaded and switches between them in the middle of the print, as often as the model requires. At every switch the nozzle has to be purged of the previous colour before the new one is laid down, and that waste is printed as a tower next to the model. That is why a model in two colours takes longer and uses more material than the same model in one, and costs more. The more layers in which both colours occur, the more switches.
The colours come out sharp where they meet, and the part is one piece with no glued joints. Two colours cannot come from an STL file, because it holds no colour. That is why the file has to be a 3MF.
Two ways to put colour in the file
The simplest is a model made of several parts, one per colour: a body and eyes, a plate and letters. In Bambu Studio you import the parts, give each part its own material in the list on the left and save the project as 3MF (File, Save Project As). That is also how most multi-colour models on MakerWorld are saved, and those you upload as they are.
The other way is to paint. Bambu Studio has a painting tool that lays colour straight onto the model's surface, and it works for models in a single part too. The painting is saved in the 3MF file and comes along when you upload.
Either way, keep to two colours. If the file holds more, two of them share one colour in the print.
What happens when you upload
Order a custom 3D print online reads the colours from the file and shows them in the preview. For each colour in the file you choose which of our stock colours it is printed in, and the page suggests the closest one. If you want the whole model in one colour, choose the same colour twice. The price is recalculated as you choose, and a minute or so later you see the exact price and a layer-by-layer preview of the print, in both colours.
The colours we have in stock are shown when you order and differ slightly between PLA and PETG. Both colours in one print are the same material: two PLA or two PETG.
What works best
- Colour per part gives a cleaner result than painting and is easier to correct.
- Colours at different heights, such as a base in one colour and the figure in another, need almost no switches. Colours that meet in every layer need a switch per layer and take longer.
- Raised lettering in a contrasting colour on a flat face works very well: the letters as parts of their own, at least 0.5 mm line width and 3 mm tall.
- Dark against light shows best. Two neighbouring shades disappoint on a small model.
- A model in one colour can be ordered in any stock colour at no extra cost. Two colours pay off when they do something for the model.
More parts and more colours
If you have several parts to print together, put them in the same file with their colours, see the guide Several parts in one file. If the model needs more than two colours, it can be split into several prints that are assembled afterwards, or painted by hand. If you are unsure how best to split the model, contact us and describe what you want, and we will suggest a way.