Hardware · build

A watch winder that keeps your automatic watch running

Adafruiton Adafruit Blog

Skip a few days and an automatic watch dies. This Adafruit build spins it on schedule, using a DC motor, a Circuit Playground Express and LEGO-compatible bricks.

Build sheet

Controller: Circuit Playground Express
Driver: Crickit board
Language: MakeCode (visual)
Frame: LEGO-compatible bricks

Can I build this?Intermediate · AI 3/5 · $50–90

Difficulty: Intermediate
AI-buildability: 3/5
Time: A weekend
Cost: $50–90

Parts

Circuit Playground Express Crickit board DC motor

Tools

soldering ironLEGO Technic parts

Starter prompt

Based on "A watch winder that keeps your automatic watch running" on Afterware: https://afterware.xyz/p/a-watch-winder-that-keeps-your-automatic-watch-running

Write a MakeCode Arcade or CircuitPython program for a Circuit Playground Express driving a DC motor through a Crickit board. Run the motor for a set number of seconds at fixed intervals so a mechanical watch on a LEGO-brick cradle is turned a set number of times per day. Add a button to pause and a light to show when it is running.

Estimates based on the original write-up. How AI-buildability is scored. Building with an AI assistant? Connect it to Afterware (free MCP server).

Story

An automatic watch runs on wrist motion, so leave it on a nightstand for a couple of days and the mainspring unwinds until the watch stops. You then have to reset the time and date. This project fixes that by turning the watch for you on a schedule.

A small DC motor drives the winder, powered by a Circuit Playground Express and a Crickit board. The program is written visually in MakeCode. The gearing and the frame are built from LEGO-compatible bricks, so the whole contraption stays easy to take apart and change.

The appeal is the mix: a cheap, approachable microcontroller, a drive train you can rebuild from bricks, and a watch that stays set. Adafruit's full guide has the details.