Fully Printable Swiveling, Locking Caster

I made a goal of designing a functional, fully 3D-printed caster that can swivel and lock the wheel. The wheel diameter is 4" so it's quite large. Although it actually functions pretty well, it won't be able to roll under much load. I did try it out by mounting 4 of these to a table which I had my Ryobi planer mounted to (pretty heavy) and they held up in static load but due to the soft TPU tire, they couldn't roll very well with that much load and ended up breaking. The locking mechanism requires that the tire be soft but maybe someday I'll improve the design. For now, I wanted to get this out there. Maybe it will inspire someone to build off of it and make it better or maybe someone will find it useful for lighter loads.

Two main versions are provided: one with the locking feature and one without. If you want the version without the lock, don't print the lock lever, lock lever switch, or lock pin. 

There are also two versions of the mounting bracket: one side-mount and one under-mount.

PRINTING:

All parts can be printed in PLA except for the lock lever and the tire. The tire is meant to be printed in TPU and the lock lever should be printed in PETG due to the built-in spring. The individual balls for the thrust bearing can be very tricky to print given that there's not much surface area - a raft can help or a first layer that's a little lower than normal. The ball bearing is designed to not need any support material. You will need 2X Swivel Hub Bolts.

ASSEMBLY:

Parts are assembled as shown in the cross-section diagram. For the locking version, compress the spring of the lock lever and snap the lock lever switch in. Then slide the lock pin through the yoke. The fit of the pin should tight through the yoke but not through the lock lever.

OTHER NOTES:

When using the lock, it's okay to press the lever down without actuating the switch since it will do that automatically. However, when releasing the lock, be sure to use the switch, otherwise you'll probably break it.