Multi Material Printing: A Practical Guide

Logan F.

Beyond Monochrome

Moving beyond single colour printing opens up an entirely different side of FDM printing. Multi colour and multi material printing allows makers to create parts with contrasting text, detailed logos, layered colour effects, and functional material combinations that would be impossible with a single filament alone.

From simple colour swaps through to advanced automated systems, multi material printing dramatically expands both the visual and functional possibilities of a printer.

Whether the goal is cleaner signage, artistic models, flexible grips on rigid parts, or dissolvable supports for complex geometry, there are several different approaches available depending on the hardware and level of complexity involved.

Method 1: Pause at Layer Filament Swaps

The simplest way to create multi colour prints is by pausing the printer at a specific layer and manually changing the filament.

Most slicers include a built in filament change or pause command that can be inserted at any chosen layer height. In Cura, this is typically done through Extensions → Post Processing → Add a Script → Filament Change. In PrusaSlicer, you can right click a layer in the preview window and insert an M600 filament change command directly into the print.

When the printer reaches that layer, it moves the nozzle away from the print and waits for the user to unload the current filament and insert the next colour before continuing.

This method requires no additional hardware and works on almost any FDM printer.

The main limitation is that colour changes can only occur horizontally between layers, rather than within the same layer itself. It also requires the user to be physically present during the swap process.

Even with those limitations, pause at layer printing is extremely effective for signage, name plates, logos, keychains, coasters, and decorative prints with clean colour separation. Using consistent, high quality filament across colours helps ensure smoother transitions and a cleaner overall finish.

Method 2: Automated Multi Material Systems

Automated systems such as the Bambu Lab AMS or Prusa MMU allow printers to switch between multiple filaments automatically during a print.

These systems hold several spools at once and feed the required filament into a single nozzle whenever a colour or material change is needed. This allows for far more complex multicolour prints, including detailed graphics, printed artwork, and highly intricate colour layouts that would be impossible with manual swaps.

The biggest downside is purge waste.

Because all materials pass through the same nozzle, the printer must purge the previous filament colour before continuing. This waste material is typically deposited into a wipe tower or purge block besides the model.

On heavily detailed multicolour prints with frequent colour changes, the amount of purge material can sometimes exceed the weight of the actual printed model itself. Material usage, therefore, becomes an important consideration when planning larger multicolour projects.

Despite the waste, automated systems make multicolour printing dramatically more accessible and convenient for everyday users.

Method 3: IDEX and Tool Changer Systems

IDEX printers and tool changer systems take a different approach by using completely separate hotends for each material.

Instead of repeatedly purging a shared nozzle, each hotend remains loaded with its material and temperature settings. When needed, the printer simply switches between active tools.

This approach greatly reduces purge waste and enables combinations of materials that are difficult or impossible with single nozzle systems.

One of the most popular applications is combining standard printing materials with dissolvable supports such as PVA. Once the print is complete, the support material dissolves away in water, leaving extremely clean supported surfaces with minimal post processing required.

Tool changer systems also allow for more reliable printing of combinations such as rigid PLA with flexible TPU sections, where each material benefits from very different extrusion settings and temperatures. (See our PVA support guide).

The trade off is complexity. IDEX and tool changer printers require more calibration, tuning, and maintenance than standard single nozzle machines. However, for advanced users and complex engineering applications, they offer an incredibly powerful level of flexibility.