MathMechs makes mathematically meaningful mechanisms. We prototype in 3D printed materials then mass-produce in injection molded plastic.


An extensor is an extending beam based on a patent pending scissor-like mechanism. The extensor construction kit lets you build expanding structures from Y-extensors (extensors with three arms) and X-extensors (extensors with four arms).

Extensors can be connected together at nodes to build larger expanding structures. You can add springs to make mechanisms jump open!

We currently offer a starter set with 40 injection molded plastic parts in four colors and 2 springs, available from for $20.

Caltrop retracted
Caltrop extended
X-extensor retracted
X-extensor extended
Included parts
Box and contents