3D Printed American Flag - Multicolor Single Extruder Printing

Multi-color 3D printing opens so many more possibilities to what you make! While there are many options for hardware and software to make this possible, in this Instructable I will be going over a technique that will allow nearly any 3D printer to create flat multi-color prints.

Step 1: Video!

Step 2: Materials

For this project you'll need only a few things:

• A 3D printer! Hopefully a well-calibrated one with a very level build plate
• Lots of colors of filament! I bought a multi-pack of PLA on Amazon. They package small amounts of a lot of colors, meant for 3D pens.
• A 3D modeling program. I'm using Fusion 360.

Let's get started!

Step 3: Design

Your design process will vary depending on what image you're trying to 3D print, but my process was as follows:

• Find an SVG of an American Flag - this was easy!
• Import SVG into Fusion 360, and scale upon import
• Edit/Refine the SVG. Some stripes and stars needed to be added. This was easy in Fusion 360's sketch editor to create a new pattern with the appropriate number of stars.
• Extrude each part of the flag into separate bodies 0.2mm tall. It should be one layer thick for whatever print settings you plan to use.
• Sketch and Extrude a "bounding box" around the flag. This will ensure that each model will be aligned properly with one another by centering on the build plate. This bounding box will be removed in between each print.
• Export one STL file with the appropriate bodies for each color, and the bounding box.

Step 4: Print!

This is pretty straightforward, though unconventional.

• Load your first file: I would recommend the lightest color you're using, and print it.
• Remove the outlines outside of your model from the build plate, and load your next file.
• Print your next file, while leaving the first model on the build plate. Because the STL's were designed to touch, the second model will be placed precisely next to the first, and fuse with it slightly.
• Repeat for all colors in your model.
• Carefully removed model from the build plate. I used a razor blade and putty knife to carefully peel if from the build surface.

I then printed the flag pole, which prints like any normal 3D model, and added the flag to it.

Step 5: Finishing and Conclusion

Even though I modeled the flag pole to have a gap to insert the flag, while printing this closed up, but was still visible. If I were printing it again, I would have enabled "do not cross perimeters" in your slicer, to try to avoid that. In my case I just carefully cleared the gap using a knife and Dremel.

Thank you for reading!