Converting a Cheap RC Car into a Wireless Door Lock

While we often feature projects built with brand new, commercially-available parts, the true spirit of hacking is in repurposing a device to do something that it was never intended for. Toaster ovens, for example, are designed to toast bagels and cook pizza bites, and yet they also make really good solder reflow ovens. That spirit is alive and well in Dante Roumega’s tutorial, which demonstrates how to turn an inexpensive RC car into a wireless door lock.

Roumega has a lot of Arduino builds on his YouTube channel Build It, but he wanted to go in a different direction with this project. His goal was to build a wireless door lock without using a microcontroller development board, which is what most of us would immediately jump to. He came to the conclusion that one of those cheap RC cars would work well because they’re wireless, battery-powered, designed for controlling motors, and can be purchased for about $10. It is worth noting, however, that the radio control doesn’t offer any security at all, so don’t use this to lock up anything important.

To start, Roumega disassembled the RC car and kept just the control board and steering motor assembly. The lock, in this case, is a simple barrel bolt style like you’d use for a gate or garden shed. The RC car’s steering motor mechanism has just enough throw to lock and unlock the bolt. All Roumega had to do was mount the control board to the body of the lock, and the steering mechanism to the bolt. Pushing the steering stick on the RC controller moves the bolt — no coding required!