Review on Stepper Couplings with Backlash Elimination and Flexibility by Chris Moody

Fits the Ender 3 Pro very well. I have found that after with almost any printer system changing with ever-tightening tolerances, there are common design flaws. I'm not saying the Ender 3 Pro isn't a great printer at a fantastic price - it definitely is! This is the definition of a truly expandable platform with unlimited possibilities. My Modifications or "upgrades" are too numerous to list ad nauseam, but I've noticed that the Z-axis transitions have a slightly uneven adjustment.This isn't just due to play in the standard brass nut, the attaches to the Z-track, but by definition also affects the overall play.A spring maintains constant tension between the two halves of the Anti-backlash nuts hold upright, and a locking tab and slot prevent both from rotating relative to each other. A small gap allows a force applied in the opposite direction, causing backlash, to be transmitted to the spring, which compresses and decompresses, canceling that force on the z-axis and anything attached to it. Viola. The problem is solved. I ended up having to place a set of M5 washers between the plastic stepper motor mount block and the frame to properly align the lead screw with the center of the hole in the Z axis plate. This is done to compensate for dead center. Two of the four mounting holes in the top half of the part lined up well with the existing holes on the Z axis plate. Easy installation and very happy with the results. As always, if anything goes wrong in the future I will update this review. I recommend and buy again. I haven't tried connectors yet, although I may not be the biggest fan of the set screw design. But I bought this set because of the two anti-clear nuts, and the couplers will be in one of my parts boxes for a day.