This is my Solder Sustainer project. It allows effortless soldering by freeing up your other hand so that it can hold the part you're bonding in just the right position without any hassle.

It does this by utilizing a pancake stepper motor, touch sensor buttons, and built in power regulation so it can tap directly into the soldering iron's AC power for added convenience. All while in a compact package designed around the ESP32-S3 microcontroller.

Demos:
https://www.youtube.com/watch?v=CI2AZPYC_qo&t=12s
https://www.youtube.com/watch?v=tgRbwhpl7jk&t=211s

My fully in-depth article describing exactly how it works and how it was built:
https://www.roboticworx.io/p/build-a-one-handed-soldering-tool

(If there's a pop-up, just simply click "DISMISS" at the bottom.)
Happy making!