Here’s a really cool DIY on how to make a PID controlled fridge.
Heck, if you want to skip the steps, you can also get a Kimchi refridgerator, which does the same thing.
I had an old beer cooler sitting in the garage that Kylie picked up on the street a while back. It uses a Peltier thermoelectric cooler to cool the inside and can achieve sub-freezing temperatures.
Since I didn’t want to leave the cooler on constantly, and below freezing is actually too cold for solder paste, I decided to add a PID controller to the cooler to create a solder paste fridge for the garage. To do this, I needed the following items: