I bought some stuffs from Misumi and this came across in their email feed.
They have a series of 19 min youtube webinars on the various stuffs they sell, ranging from linear bearings to gears to shafts. If you’re a noob to building 3d printery stuff like me, they’re pretty interesting.
https://www.youtube.com/playlist?list=PLa2jI_3JolEvaYVYqO5NaJu93nMYdQsai
-D