19T Gates Powergrip GT2 7.5mm pitch Genie Garage Door Belt Pulley for repurposing

Openscad // --- User Defined Parameters --- teeth = 19; pitch = 7.5; width = 11; shaft_dia = 11.9; tooth_depth = 3; land_width = 1.4; // --- The Variable Controlling Diameter --- // To get a 47mm diameter, we set the radius to 23.5 outer_radius = 23.5; // --- Calculated Geometry --- $fn = 120; total_angle = 360 / teeth; // This math now uses the new 23.5 radius land_angle = (land_width / (2 * PI * outer_radius)) * 360; groove_angle = total_angle - land_angle; groove_width_at_rim = 2 * outer_radius * sin(groove_angle / 2); module pulley_final() { difference() { cylinder(h = width, r = outer_radius); translate([0, 0, -1]) cylinder(h = width + 2, d = shaft_dia); for (i = [0 : teeth - 1]) { rotate([0, 0, i * total_angle]) translate([outer_radius, 0, -1]) scale([1.9, groove_width_at_rim / tooth_depth, 1]) cylinder(h = width + 2, r = tooth_depth / 2); } } } pulley_final();