BigWheel In-Line Switch

The BigWheel in-line switch is designed for low voltage DC applications only. DO NOT use this as a high voltage AC switch. If you burn your house down, don't say you weren't warned.

Unlike most of the designs on Thingiverse (some of them my own), this is not a housing or enclosure for a manufactured switch, but a home brew switch from the ground up, The principle is pretty basic: a rotating wheel with a conductive strip attached so it bridges the gap created in the positive wire of the circuit.


This uses 24 gauge speaker wire and a snippet of aluminum from a beverage can. Cut a strip of aluminum 8.5mm x 18.5mm. Be sure to scrape off the thin layer of epoxy that coats the inside of the can; it's an insulator and the switch won't work unless you're down to bare metal.. Wrap the aluminum around a small cylinder (8mm ±) in order to create a curve to make it easier to feed into the slots in the wheel.

As for the wire, snip the positive wire only and strip about 5 or 6mm of insula