Outrunner Belt Reduction Drive

There seems to be an STL issue with “Inner Shell”. please check if m3 heatset holes are blocked. Bambu and Orca slicer seem to not have this issue, but Prusa slicer does. Printables model viewer also has this.These filled holes can be cut out with a negative modifier if needed.Hardware:Small bearing x12 - 3mm inner diameter, 10mm outer diameter, 4mm depthLarge bearing x1 - 20mm inner diameter, 27mm outer diameter, 4mm depthGT2 Timing belt x1 (GT2 540-2M-06 RD015) Maker's supplyM3 heatset inserts x12 5mm outer diameter, 4mm lengthNema17 Stepper motorGT2 aluminium pulley 16TB5W6 M3*8 machine screw x12M3*12 machine screw x4 (for mounting stepper) Primary function as a demonstation piece. High Mounting holes: hexagonal shape. 40mm from center, 40mm hexagon edges, 3.2mm diameter^ Mounting pattern on both sidesHeight: 30.5mm +-0.5mmdiameter: 142mmThe belt is inverted, with the teeth gripping the outside shell.Tips & AdviceUse a small amount of lubricant on the smooth side of the beltPrin