On a whim, I purchased a $20 USB Solder Iron from Aliexpress to play with. After playing with it using an old phone charger, I saw a video on Adam Savage’s Tested channel and got inspired. Drill Batteries as the power source. What a great idea! I have lots of those and always keep a few charged up and ready for projects. However, finding a drill battery adapter for my Black and Decker 20V set was a challenge. It’s all discontinued. Black and Decker only sell new bluetooth batteries with USB ports built in. No adapters to be found. Searching for a solution, I found forum posts saying that black…