Multi-material unit

What is Multi Material Upgrade?

Quote from prusa’s website.

It’s exactly what it sounds like - it’s an optional add-on that allows your single-extruder printer to print with up to 5 colors (materials) at the same time. The MMU3 contains five filament insertion points. Load up to five colors of your choice, slice the object in PrusaSlicer and start the print. The system automatically selects filament using the selector, loads it into the extruder and the printer starts printing. When it’s time to change the color or material, it also happens automatically.

With such a mmu I am able to print an object in different colors in one layer or printing with different materials such as PLA and PETG. For example, printing the object in PETG and the support structure in PLA to improve the detachment of the support structure.

How it works

The first filament is fed from the MMU to the print head, from where it is picked up by the extruder. Each time a filament is changed, the existing filament is pulled back from the MMU. The filament is pressed into the filament box so that it does not become loose on the spool. Here it cannot become tangled due to the individual separation.

Filament storage

Next, the MMU selector moves to the next filament and picks up the filament there.

Filament change - wipe tower

Every time the filament is changed, the nozzle must be cleaned. To do this, a wipe tower is created next to the print, on which the remaining filament in the nozzle is printed.

Here you can see a test print (5 color circle) with the corresponding wipe tower. The ratio between the actual print and the wipe tower varies depending on how many color changes were made. In this case, the ratio is 1:4.

Filament storage

If you had printed 4 circles instead of one, the wipe tower would have remained the same. For this reason, it is worth printing the actual object several times to reduce the ratio of the wipe tower.

Yes, the name of my printer is “Drucki” 😄

Disclaimer

Photo/Video from Prusa on Prusa3d