Reuleaux Triangle Constant Width Math Toy

Design preview. Rendered from the file, not a photo.
This model is not currently offered as a verified ready to buy print.
What it does
- Rolls smoothly under a flat board, just like a circle
- A hands-on demo of constant width geometry
- Sparks great math conversations with kids and students
- Sits on a desk as a quiet conversation piece
- Fun for STEM teachers, students, and math lovers
You set a book on top of three of these and roll it across the desk. The book glides like it sits on round wheels, even though the shapes are not circles. That is the magic of constant width.
The Reuleaux triangle is one of the classic shapes of geometry, and this volume of revolution version turns the lesson into a hands-on toy. Drop it on a desk, roll it under a notebook, or pass it around a classroom.
Use it as a math teacher's prop, a STEM gift, or a quiet desk piece that earns more questions than most office decor does.
11k downloads in the maker community. That is interest in the design on the site it came from, not our sales.
What you get
- This design prints as one piece.
- Nothing else to print or buy for this to work.
What it is made of
Designs like this print well in PLA. Compare the materials.
Printed plastic is strong for its size, but it is not metal. We have not load tested this design, so we do not publish a weight rating. Keep it out of a hot car and away from open flame.
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Who made this design
Designed by Intentional3D. We did not draw it.
Shared under Creative Commons, credit and share alike. See the original design