Hictop Prusa I3 Y-Axis Belt Tensioner

thingiverse

I acquired my Prusa i3 printer from Hictop on Amazon in February 2015. Initially, adjusting the y-axis belt tension involved flipping the entire printer over and manipulating the cable attachment points to tighten the belt. This process quickly became frustrating. I discovered another similar tensioner, part #807702, and adapted its design to fit my printer. This modified design works effectively and I hope it will help others with similar belt tension issues. The axle bolt is 8mm in diameter and features an 8x22x7 bearing. The attachment hardware consists of 3mm machine screws used for both the bearing housing and the tensioning screw. You'll need to drill a new hole for the tensioning screw; otherwise, this assembly serves as a direct replacement for the original part. When adjusting the belt tension, pay close attention to avoid over-tightening, which can cause excessive stress on the belt. If the y-axis is under too much tension, it may malfunction or cause the stepper motor to skip steps. To achieve optimal belt tension, loosen the 8mm bolt nut and any associated jam nuts. Tighten the tensioning screw by hand while checking the belt's tightness. Once satisfied with the belt tension, secure the 8mm bolt nut and any jam nuts (if used). Finally, perform a calibration test to ensure printer operation is accurate.