MakerFarm i3v X or Y idler belt pulley for 12mm bearings

thingiverse

This is a modified version of Zen1's i3v push fit belt guide from http://www.thingiverse.com/thing:359773, built upon an upgraded openSCAD script sourced from Parametric Pulley, available at http://www.thingiverse.com/thing:16627. The pulley can be used as either the x-axis or y-axis idler in the MakerFarm i3v printer. Changes to the original design include increasing the pulley_t_ht parameter from 6.2mm to 6.5mm for a more secure belt fit; reducing the idler_ht and retainer_ht parameters from 1.4mm to 0.75mm to achieve an overall width of 8mm for better bearing alignment on (2) 4-mm wide bearings; adding .1mm additional_tooth_depth to ensure the belt isn't solely reliant on compressible teeth; and increasing the number of teeth from 25 to 26 for enhanced print quality. To improve the openSCAD source, a chamfer was added to the shaft hole, making it easier to insert the i3v 12mm OD bearings. The MCAD library polyhole is used instead of traditional hole definition, providing more precise dimensioning. For optimal printed results, ensure high-quality teeth on the pulley. Check for well-shaped teeth and minimal stringing issues, particularly with PLA, which requires a print cooler or alternative techniques to manage thermal print issues.