Triangular Rollers - 1
Making triangular rollers. Step 1 - turning a glued-up stack of boards into a hexagonal prism, producing a big pile of wood shavings in the process.
A curve of constant width is a two-dimensional shape whose width, as measured with calipers, is the same, regardless of the orientation of the curve relative to the calipers. You can extrude such a curve into a three-dimensional roller that will have a constant height as you roll it around on a flat surface. A board supported by a pair of such rollers will move horizontally without any up and down motion. A circle is a curve of constant width, but it's not the only one; there are many others. A Reuleaux triangle (an equilateral triangle where each side is a circular arc centered on the opposite corner) also has constant width, and you can use it as the basis for rollers that look like they shouldn’t work at all. Inspired by my daughter's high school project I made an example out of wood.
Triangular Rollers - 1
Making triangular rollers. Step 1 - turning a glued-up stack of boards into a hexagonal prism, producing a big pile of wood shavings in the process.
A curve of constant width is a two-dimensional shape whose width, as measured with calipers, is the same, regardless of the orientation of the curve relative to the calipers. You can extrude such a curve into a three-dimensional roller that will have a constant height as you roll it around on a flat surface. A board supported by a pair of such rollers will move horizontally without any up and down motion. A circle is a curve of constant width, but it's not the only one; there are many others. A Reuleaux triangle (an equilateral triangle where each side is a circular arc centered on the opposite corner) also has constant width, and you can use it as the basis for rollers that look like they shouldn’t work at all. Inspired by my daughter's high school project I made an example out of wood.