I bought this one: https://www.omc-stepperonline.com/precision-planetary-gearbox/nema-23-stepper-motor-l56mm-gear-raio-1001-high-precision-planetary-gearbox-23hs22-2804s-hg100.html which has a 14mm diameter shaft with a key fitting. I’ve looked for hours for a 14mm bore hub with a key fit. Very difficult to find such a thing. Hard to find a hub clamp. Hard to find a coupling that fits it. Should I be trying to only buy stepper motors that have certain sized shafts or shafts of a certain fitting to make it easier?