Anet A8 z-axis threaded rod riser

thingiverse

These spacers are engineered to elevate the threaded rods by 8mm, causing them to protrude into the recesses on top plates of the a8 frame. Without these spacers, the rods tend to wobble excessively, deviating from their normal behavior. Initially, I adjusted the height of the rods manually into the recesses and tightened up the grub screws on the motor to shaft coupling. However, over time, I noticed that the air gap between the top of the z-axis stepper motor shaft and the bottom of the threaded rod decreased due to the weight of the x-axis assembly, necessitating constant bed levelling. This occurs because the coupling behaves like a spring, allowing for slight compression or stretching. The Anet couplings are designed to provide some flexibility should the z-axis be driven into the bed, but they also compress under the weight of what they carry, ultimately curing the issue at hand.