Oldham Coupler

The cheapest coupler I could find

When the stepper motor rotated, it sounded like a part of its rotation required more effort. Ultimately, the threaded rod isn't precisely held in place (or is bent...), and my straight aluminum tube coupler wasn't allowing any misalignment with the stepper motor. After reviewing slotted, helical (beam), and oldham couplers, I found that oldham couplers offered the most misalignment allowance for my dimensional specifications. The hole in the table is about 18mm and a height right about 29mm, which is quite small for most couplers, and prevented me from using a clamping collar instead of a set screw. Using this coupler eliminates the z-wobble I had in my prints.