Introduction: STEMFIE Rubber-Band-Driven Car

About: The 3D-printable construction set at

This toy car is easy to 3D-print and quick to build. It is the first project demonstrating the new and fully 3D-printable educational construction set toy; you can download from

This project exhibits the retention and controlled release of energy to achieve motion. The inspiration for this design is borrowed from science classes in schools, using the mousetrap challenge.

Assembly video:

More information:

Stay tuned at and here on Instructables for future releases of new projects and construction set parts.

Step 1: Download and 3D-print All Parts

Download the four build plate STL files and 3D-print them. The following settings are recommended.

  • Material: PLA
  • Layer height: 0.2 mm
  • Perimeters (shells): 2
  • Top solid layer count: 4
  • Bottom solid layer count: 3
  • Infill: 15%
  • Generic print speed: 50 mm/s

You can also 3D-print the Spanner (SPN-TOL-0004) and driver (SPN-TOL-0001).

Apart from the 3D-printed parts, you will also need a short piece of string, as well as a few rubber bands.

Step 2: Assemble the STEMFIE Car

Follow the steps in the illustrations. Note that there are two types of nuts; one with a thread and the other is a cam-locking nut, which you only need to turn 90°.

The final two steps, illustrate the placement of a piece of string (with a looped knot in one end), as well as attaching the driving rubber band and the friction band around the rear wheels.

Short assembly video:

Step 3: The Final Assembled STEMFIE Car

Finished! :-D

Make two or more STEMFIE cars for your school class and challenge students to modify and improve on the car to make it go further.


Paulo Kiefe

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