Last night I had some time on the lathe and made a new 8mm-5mm coupler because my first one was just stupid big. I also made two rod caps with set screws to hold the end of the steel rod in the carriage mount. I still need two more of them, as well as two more for a smaller rod in the pulley mechanism.
You can also see where I cut a rectangle out of the carriage mount front and back, and CA-glued in 1/4″ delrin rod to protect the enamel wire as it feeds through. Next step is to figure out how I’m mounting the limit switches to control back-and-forth motion, then it’s assembly time!