You can build a working combination dial safe using the Circuit Playground Express, a servo motor, a box, and a few magnets, wires, and batteries!

The Circuit Playground Express has everything we'll need to act as a dial that measures rotation, can give feedback through colored lights and sounds, and even control the lock!

You'll be able to code it all in CircuitPython, including reading the built-in accelerator, setting a custom combinations, and more! Plus, you don't need any compilers or IDEs, just a text editor and a USB cable to connect.

1 x Circuit Playground Express
with CircuitPython
1 x Micro servo
with servo arms
1 x 3 x AAA Battery Holder
with On/Off Switch, JST, and Belt Clip
1 x Rare Earth Magnet
high strength
1 x Magnetic Pin Back
with foam tape

Materials & Tools

You can use any lidded box of your choosing, but a really good choice is the black, cardboard Adafruit box!

The only tools you'll need are a small Philips screwdriver and some Scotch tape. Optionally, you can use a silver or white marker to decorate your safe.

This guide was first published on Dec 11, 2017. It was last updated on 2023-12-05 11:34:17 -0500.

This page (Overview) was last updated on Dec 05, 2017.

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