Extruder using 6mm Burr instead of hobbed bolt for Prusa i3

thingiverse

Remixing a no-hob extruder idea, this design utilizes a Linbide SB-1MM tungsten carbide burr with a 6mm shaft (approximately $26) for hobless filament feeding. Designed using Tinkercad, the model is compatible with Budish or J-Head extruders and can be edited to fit other extruder types. The extruder features two bearings with 6mm ID, 19mm OD, and 6mm width for the burr. A standard Wade idler for 3mm filament is required, and an idler STL file will be uploaded soon. The key to this design is the Linbide burr, which stays in place due to its smaller shaft diameter than the burr itself. Created in TinkerCAD, the model can be ungrouped and edited as needed. Designed for Prusa i3 with vertically spaced X rails, it may fit other designs but compatibility is not guaranteed. All bolt holes and captive nuts are metric, and the burr shaft is manually sanded to fit into the 6mm ID bearing. The Bill of Materials includes a printed idler (standard Wade), Linbide SB-1MM burr, NEMA 17 motor, bearings, an 8mm shaft for the idler, bolts, nuts, and springs for idler tension.