This model was built to demonstrate that an odd number of gears arranged in a closed ring on a standard (half-twist) Möbius loop do mesh - odd numbers of gears meshing in a plane do not.

Twenty-one Multi-Purpose Meccano Gears are used here, the required relative twist from one gear to the next being readily accommodated by these particular gears. A MeccParts geared motor drives the white gears at the bottom, the ring of gears being suspended from the overhead support.

This model came about from the observation that a closed circuit of an odd number of gears (19) is shown in mesh on the reverse of a £2.00 UK coin, which will not run, but that perhaps the gears might run if arranged in a Möbius loop - and they do!

Completed July 2018.