This is my Solder Sustainer project! It allows the user to solder with only one hand by directly extruding the solder via a motorized extruder gear attached to the iron. I decided to build it after getting tired of spending a bunch of time setting up pin headers before soldering them. Now, I can just hold whatever I'm soldering in place with one hand and extrude solder on the joint with the other!

It works by using an ESP32-S3 microcontroller to control a pancake stepper motor. The extrusion mechanism is spring-loaded, so the solder is always firmly pressed against the extruder gear. No slippage!

There are two touch sensor pads driven with NPN transistors to detect if your finger is over the forward or backward button. If it is, it will extrude solder in that direction!

In addition, it has a built-in 5VDC rectifier so it can be completely plug-and-play with the solder iron's AC current.

The rest of the BOM for this project as well as some additional information on building it, how it works, etc. can be found here on my webpage: https://www.roboticworx.io/i/135306051/bom