Developing robotic joints may seem like a daunting task, but there are some common issues that can be addressed ahead of time to make the project more manageable. There are a lot of parts to fill in a small space, usually, a joint has motors, transmissions, encoders, brakes, electronics and wiring. One of the most common tasks is managing the assembly of bearings and gearboxes with housings. This article provides guidelines for mechanical assembly and precision-fit machined parts.