The music box is coming along, in fact it’s fairly close except for final assembly. I realized I’ll need to mount each key to the octagon and then mount that entire structure to the base board. I could have chosen some alternate mounting method, though I wanted to keep the mounting hardware hidden, so that’s what I’m left with. Everything else is ready to go! The keys are made with strings (though untuned), the octagon from PVC is made and painted, the drive chain is mounted and the baseboard tuned. I realized when I tried to crank one of the first times the derailleur sprockets glued together wasn’t going to hold; I needed deeper teeth. I instead went with a 2 sprocket bike cassette and ground off the petal with an angle grinder.
Either way, we’re now ready for assembly. I’ve attached a few assembly photos below, laying out the octagon first so I could center the chain.