Here is a simple project I recently completed. I needed a footswitch controller for my Peavey Studio Pro 110 amplifier. It’s a very nice amplifier for small apartment use and I bought it used for a very decent price – the price was low partly because it was missing the footswitch controller.
The actual controller is quite simple inside, being composed of two switches and two LEDs connected to a 1/4″ stereo audio cable that plugs into the back of the amplifier.
What I created was a set of three plastic printed parts (nice and thick for sturdiness) and then painted them for a nice finish and then wired it all up and glued the case together.
You can get the messy source files as well as the ready-to-print STL files on my GitHub for the project: https://github.com/novakanereprap/peaveyswitch