I completed the wiring last night, which required a lot of hunting down specs, cutting a slightly larger hole for the OLED connection, and a few other things. I installed the OLED with the M2 screws I received in the mail yesterday (check out Bolt Depot, they’ve been a great source of bulk bolts for me).
I wired the Arduino UNO into the 12v power supply, and soldered some pins onto the custom stepper controller board to use its extra grounds. I simplified the wiring with larger connectors where it made sense.
I started working on the code for this the other day, and am pretty close to complete and ready to do some serious testing. I hope it doesn’t blow up when I plug it in.
I also reversed the bolt/nut direction on the idler pulley. Originally the bolt came up through from the bottom with a washer and nut on top of the pulley. When glued in place, it made it nearly impossible to loosen, so I changed it.
The few things left on my TODO list are to set the reference voltage on the DRV8825 drivers (for my 2A stepper motors, that should be 1.0v according to the documentation I found), and to possibly redo the coil stepper’s coupler (again) so it’s sturdier this time. It’s also possible I’ll have to tweak the stepper control board and change from full step mode to microstepping (it supports up to 1:32 microstepping) to handle moving the carriage the small distances the wire diameters require.
I’d also like to redesign the assemblies to have a locking piece under the base that would hold them in place instead of gluing them down, so I could take it back apart. Ah, hindsight…