Prusa MK3s Extruder Carriage for Bear X-axis

thingiverse

This is an upgraded R4 extruder carriage for Prusa MK3s / MK2.5s, designed to be compatible with pekcitron's Bear X-axis. The MK3s still lacks a decent X-axis belt tensioning mechanism. The original Prusa carriage was modified in Solidworks based on the sources by jzkmath. The belt path was altered to match that of the Bear Extruder while maintaining compatibility with the MK3s extruder. The belt channel was tightened relative to the original Prusa model to prevent slipping and extended beyond default length for accommodating longer belts without trimming. The back part of the carriage was modified to maintain belt access in its new position. Update [17/4/19]: My MK3s upgrade parts arrived, and I assembled and verified the Bear X-Axis - MK3s extruder mod. It works perfectly! During assembly, I discovered that the required belt length decreases from stock MK3 X-axis to Bear one, but the lengthened channel accommodates this change. Update [27/4/19]: Using Igus RJ4JP bushings with this carriage revealed excessive play due to Prusa's oversized cutouts. A remix was created to snugly fit around these bushings. If using RJ4JP bushings instead of linear ball bearings, look for the remixed version for optimal performance.