How it works: Multi color 3D Printing

Hobbyist 3D Printing for fun or projects is cool and with colors straight out of the printer is the coolest 3D Print object ever. 3D Printing of dual or multi-color or even multi-material has been possible since the first release of open-source 3D Printing. 2013 MakerBot Dual Extruder is the first jump step for consumer multi-color/multi-material 3D Printers grown rapidly since then.

There is no doubt that FDM/FFF technology 3D Printing is the easiest and cheapest to produce cool 3D Printing project, so development significantly improved for both consumer and industrial market segment. Types of material and color variation for 3D Printing Filament have become main topics and attractions to show off in the 3D Printing Industry. Even a lot of vendors and producers of 3D Filament material now releasing attractive multi-color 3D Print Filament with good acceptance in the market.

Here are technology methods for Color 3D Print available in Filament 3D Printing in the market.

Layer color Changing (Pause/Resume)

This is the basic method to create color for 3D Printing by manually changing the filament with other colors using Pause/Resume during the print process. Its time consume and tedious process as a user has to attend the whole-time process and perform Load Unload Filament for color change. This method only changes color on Z-axis direction so it’s only layer change color. There is no way to perform XY color change with this method.

Dual Head / 2in1out Hot end / IDEX

This breakthrough base idea came from MakerBot in 2013 which uses Dual Head so 3D Printing Filament can print 2 colors or even 2 materials in 1 working process. Users no need to attend for color changes and everything is handled automatically. More improvement and variation from this idea came to 3D Printing Industries like dual or multi-input single-out hot-end/nozzle or Dual X-axis head movement (IDEX / Independent Dual Extruder.

Dual Head and IDEX is a simple process - the printer extrudes the material on which the head is assigned for that particular model. Yes, it always needs a separate 3D model to process each individual head.

The dual/multi-in single-out process is more complicated as 3D Printer uses a retraction mechanism to pull out material from the hot-end and push in new material from another extruder. This mechanism is only applicable using Bowden style extruder.  

Multi-color kit (change filament)

Mosaic Palette

Back in 2015, Chris Labelle launched a new add-on machine called Mosaic Palette which can mix 4 materials using a cut and fuse (called splice) mechanism to create multi-color filament and from there filament can be fed to any 3D Printer. This is a huge idea as, with these methods, not only 4 colors 3D printing Filament can be produced but a lot more than that. This machine needs integration with slicer software to perform and it’s not an easy preparation task. The other drawback is this only can be performed with PLA due to its material characteristics.

Prusa MMU and Tool changer

As a pioneer in the consumer 3D Printing Industry, Prusa also released multi-material multi-color add-on units in their creative product line. The mechanism is to pull out the Filament from the extruder until the exchanger unit. This exchange mechanism takes a lot of time to process but it's cheap and easy to implement.

Prusa also provides another, more efficient multi-color solution called the Tool Changer. Its extruder and nozzle are separate. One printer can have up to 9 extruders, allowing it to print with 9 colors. When one color of filament finishes a section of the print, that extruder separates from the nozzle and another extruder fits together with the nozzle to continue the 3D printing.

Prusa MMU

ERCF / SMuFF

Enrage Rabbit Carrot Feeder (ERCF) and Smart Multi Filament Feeder (SMuFF) are similar to Prusa MMU external modules. Both units' models an OpenSource development projects and are only available in DIY projects rather than released consumer products.

BambuLabs AMS

The first release of the Popular BambuLabs 3D Printer directly came with multi-material / multi-color options called AMS (Automatic Multi Material Module). The module mechanism is also similar to Prusa MMU system and does pull retraction of the Filament until the Module Unit. The popularity of this is because it’s easy to implement and maintain. The good thing with BambuLabs is that they provide an Integrated Environment system so users don’t have to tinker with setting the 3D Printer and print color out of the box with less hassle.

Multi-color 3D Printing requires a separate STL 3D model to print each color. This is a must as the slicing software only recognizes each process based on 1 solid model.

All Filament 3D Printing multi-color exchange process definitely consumes a lot of waste material and much longer time. This is called a purge / wipe system so the previous filament color is completely clean from the hotend and nozzle. In single nozzle multi-color 3D Printing, avoiding multi-brand / multi-material (examples: from pla - abs) is a must. Successful multi-color 3D Printing needs stable flow and temperature.

Here are two important tips that you can reduce purge/waste material:

1. Multicolor small object - print a multiple. One small print object will spend exchange process time and use waste material almost the same as multiple objects. So rather than printing only one - just add a few more in one print process.
2. Use infill as purge tower transition process. Current multicolor slicers like Prusaslicer or orcaslicer have the setting option to turn infill as a purge tower during filament exchange transition. It will definitely reduce time and waste material.

Multi-color 3D Printing is a consumer favorite as it can 3D print directly in color without too much manual handling and post-processing. Single nozzle color FDM 3D Printing is still affordable for most users compared to other 3D Print Technology.