Soldering irons are one of the staples in every engineer’s tool box, and finding the right one that works for you is a personal endeavor. For some, building their own is the way to go, and I’ll admit, I never thought of making my own like Tindie user “vlk” has, with his RT Soldering Pen that accepts the popular Weller RT tips.
According to vlk, he was looking for specific features in a soldering iron, “The idea was to build my own but with very specific qualities. On one side it’s not so expensive, on the second side, it’s high quality and also small with precise control and features.” His solution was to create his own with some exciting features, including a WRMP soldering iron with a standard 3.5mm jack that can accept Weller RT tips.
The most unusual aspect of the RT Soldering Pen is the microcontroller with, which is outfitted with an Arm Cortex-M0 MCU that processes temperature data garnered from a thermocouple housed in the tip and puts that data on an embedded 128 X 32-pixel OLED display.
vlk is selling the RT Soldering Pen on Tindie for $54, which includes the board only — you’ll need to buy your own Weller tip and power supply (7–15V recommended). You will also have to make your own case, as it doesn’t come with one. Users can program the board with any ST-Link SWD platform, and vlk has uploaded the firmware source code, binary release and documentation on his GitHub page, and has hosted the schematics (in PGN form only) on his project write-up here.