Coloring Models with Materials and UV Maps

In this chapter, you will learn how to add colors to your model for full-color printing at a 3D Printing Service Bureau. The skills include:

• Adding new materials and setting their colors
• Assigning materials to specific faces
• Adding a new Editor Panel to Blender's interface
• Unwrapping your model for more advanced coloring
• Using Blender's Fill and Draw brushes for painting
• Exporting your work to X3D format and uploading to a Service Bureau

Using materials

For most printing processes, the color you put on your model in Blender has no impact on the color of the final print. For the FFF/FDM printers, the color of your print is going to be the color of the filament(s) you have loaded into the machine. SLA will be dictated by the resin being used. For the 3D Printing Service Bureaus, you may be picking a dye color when you order your prints.

The exception is the full-color printing 3D Printing Service Bureaus offer in Sandstone (gypsum powder) and now Plastic. Those printers need color information. In Blender, one way you can add color is by adding and assigning single-colored materials to your objects and faces.

Adding a material to the whole object

The steps to...

Coloring with UV Maps

Another technique for adding colors to your model is to unwrap your object to make a flat 2D representation of the surfaces, which is called a UV Map. That 2D image can be colored and decorated. Your colors would not be limited to specific faces. UV Maps give you the ability to add very specific details and shading to your object. You can color the image inside Blender with a process called texture painting. You can also work with an image editing software you are already familiar and comfortable with. In either case, the very first step would be making the UV Map to color.

Adding a new panel to Blender

When working with UV Maps, it is helpful to add another panel to Blender. This will give you visibility...

Exporting and uploading X3D files

Once you are satisfied with your model, you will want to export it for 3D printing. The STL file format we have used for the other projects does not include information on the colors and materials. For a full-color project such as this one, we will want to use a format called Extensible 3D Graphics to make an X3D file. The steps are as follows:

1. In Object Mode, right-click your object to select it. In this case, I select my hand.
2. Go to the File menu at the very top of the screen. Click Export and pick X3D Extensible 3D (.x3d):

Telling Blender to export the model to X3D format

3. Customize the filename, if desired, and click the Export X3D button:

Clicking the Export X3D button saves the file

If you only colored your model with materials and did not use a UV Map or Texture Painting, then this X3D file is all you need for the 3D Printing Service...

Summary

In this chapter, you learned how to use the full-color capabilities of the 3D Printing Service Bureaus by exploring two ways of adding colors to your 3D model. First, you learned how you can add and assign materials to specific faces. Next, you learned how you can unwrap the surfaces of your model into a flat UV Map. You saw how UV Maps could be colored within Blender or outside of Blender in image editing software. You learned how to export your work into the X3D format that supports color information. Finally, you uploaded your work to a 3D Printing Service Bureau.

Sometimes 3D modeling for 3D printing can be a bumpy road. In Chapter 15, Troubleshooting and Repairing Models, you will learn how to troubleshoot and resolve common modeling issues.