There is an ancient and effective standard interface for artisans. It's called technical drawing. If you spend the time defining your part in those terms you can scale manufacturing and have redundant suppliers. Further, these days to many fabricators you can send 3D models instead of the drawings. For product design exceeding tiny quantities, such an approach offers benefits over non-scalable self-fabrication with unprofessional tooling that will ultimately limit your access to a broader range of fabrication processes and materials. I've banned 3D printers in our office for that reason. We occasionally 3D print outside, but more often these days just get metal CNC'd.