How to Print Dual Colors Using a Dual-Extruder Lulzbot 3D Printer & Cura

2023-10-02 | By Maker.io Staff

Using a multi-extruder printer allows you to create even more elaborate printed parts than ever, without the overhead of manually swapping filaments or the assembly of multiple smaller prints. Multi-material 3D prints not only create stunning visual effects and intricate details, however. They also let you take advantage of different material properties, such as choosing a material with higher rigidity to create infill structures. This article discusses how you can use a Dual-Extruder LulzBot TAZ Pro printer and Cura LulzBot Edition to create multi-colored prints.

Modeling for Multi-Color 3D Printing

As with any 3D print, you must consider the model’s shape and how it affects the print process. When creating models for multi-colored 3D printing, you must also consider the different colors certain parts of a model should have. For that purpose, you must create a new shape or mesh for every part that should have a unique color. All connected components that should have the same color can share a single connected mesh — this additional constraint can be tricky to implement, especially for beginners, as it requires thinking about a model differently.

Take, for example, a two-colored keychain that lets you quickly identify various sets of keys. The entire base of the printed part should be in one color, while the raised text within should have a different color to make the text easy to read from a distance. The 3D model, therefore, consists of two meshes, where each mesh contains multiple combined shapes that will share the same color in the end:

How to Print Dual Colors Using a Dual-Extruder Lulzbot 3D Printer & Cura This image shows the design used throughout this article. Note that the text and the backplate are two separate meshes.

Once finished with the modeling process, you must export all model parts as separate meshes and then place them on the build plate in Cura:

Place the individual meshes in Cura.

Note that Cura places the shapes next to each other on the build plate, and the program won’t let any of the shapes overlap without changing some settings first.

Configuring Cura LulzBot Edition for Multi-Extruder Printing

Start by setting up your multi-extruder printer in Cura if you haven’t done so already. To begin, navigate to the printer settings by clicking the green bar in the top right corner of the program or by choosing “Manage Printers” from the settings menu:

How to Print Dual Colors Using a Dual-Extruder Lulzbot 3D Printer & Cura Use the green button in the top-right corner of Cura to select or add a printer.

Click the “Add” button on the newly opened pop-up window and select your printer from the list of available devices. You can assign your printer an optional name before clicking the “Add Printer” button to finish the setup process:

How to Print Dual Colors Using a Dual-Extruder Lulzbot 3D Printer & Cura Select the correct printer from the list of available devices and save the settings.

Then, close the options menu and choose the newly added printer using the green bar in the top right corner of Cura.

Setting Up Multi-Colored Prints in Cura

Cura displays additional options once you add a multi-extruder printer. These additional options let you assign selected shapes to one of the printer's extruders, which could all have different filaments loaded. Select all meshes that should be printed in one color, such as the base of the keychain label, and then click the highlighted button to assign the selected meshes to the first extruder:

How to Print Dual Colors Using a Dual-Extruder Lulzbot 3D Printer & Cura Follow the highlighted steps to assign all selected meshes to the first extruder.

Repeat the same steps for all meshes that should be in a different color. This time, however, assign the selected meshes to the second extruder:

How to Print Dual Colors Using a Dual-Extruder Lulzbot 3D Printer & Cura Repeat the same steps to assign the other meshes to the second extruder.

All meshes assigned to a different extruder than the one selected in the right menu bar will appear half-translucent in the preview, helping to identify the parts the active extruder will print.

Next, use the right menu bar to change the extruder settings. Cura LulzBot edition supports using completely different settings for all extruders, depending on the loaded material. Start by selecting the correct materials for each extruder:

How to Print Dual Colors Using a Dual-Extruder Lulzbot 3D Printer & Cura Change the extruder options by following the highlighted steps.

Then, repeat the same steps for the second extruder. In this example, I added a white PLA material setting to Cura and chose the print profile with the highest level of detail to ensure good results. Note how the preview changes to reflect the selected material:

Repeat the same steps for the second extruder.

Combining Meshes in Cura

At this point, you configured Cura to print multicolored models using a LulzBot dual-extruder 3D printer. However, the meshes are still separated and also misaligned. To change this, select all meshes you want to combine into a single, coherent object. Then, right-click anywhere in the preview window and select the “Merge Models” option:

How to Print Dual Colors Using a Dual-Extruder Lulzbot 3D Printer & Cura Select all meshes that belong to the same model and use the merge option in Cura to combine them.

After this step, Cura rearranges the meshes to align, given that your 3D editor exported the model’s individual parts correctly. Since the overall combined model could end up a bit misaligned, click the combined model and then reset its position to the coordinate system’s origin:

How to Print Dual Colors Using a Dual-Extruder Lulzbot 3D Printer & Cura Double-check the model’s alignment and correct it, if necessary.

Once done, export the model to GCODE or send it directly to your printer via USB or a wireless connection. Cura and the printer automatically handle switching the filament at the appropriate points in time so that you can sit back and wait for the print to finish:

How to Print Dual Colors Using a Dual-Extruder Lulzbot 3D Printer & Cura The multi-colored 3D print right after printing and before applying any clean-up measures.

Summary

Creating multi-material 3D prints can introduce stunning visual effects to the finished parts. You can further use this technique to utilize different materials for structural parts of a print — achieving specific properties, such as more rigid infills.

How to Print Dual Colors Using a Dual-Extruder Lulzbot 3D Printer & Cura The finished two-tone print makes the raised text easier to read from a distance. The raised letters also provide tactile feedback to quickly find the correct key in a pocket or bag without looking.

The process begins with splitting the model into parts in a 3D modeling or CAD program. You should create a new part for every component with a different color or material before exporting each part as a separate mesh.

The next step involves importing the separate meshes to Cura and changing the settings within the popular slicer program. Once you set up the two extruders, you can assign individual parts of the model to each extruder before using Cura to combine the separate parts into a whole model.

Before starting the print, double-check the combined model and its alignment on the build plate. The printer will automatically take care of switching between the extruders at the necessary points in time, so you can sit back and enjoy the print process.