K'Nex Red Gear Replacement

prusaprinters

<p>This is a replacement for the large red gear in K'Nex toy sets, and includes the hooks and holes for the pink/brown clip to fit into, as well as smooth teeth to mesh cleanly with chains or other gears. This appears to be K'Nex part 90985.</p><p>There are two versions: a “printable” version and a “normal” version. The “printable” version is best for an FDM (plastic extruder) printer, as it does not have empty space on the bottom of the gear, which would otherwise require supports which could be difficult to remove. The “printable” version should be sufficient for all normal K'Nex uses, as the pink/brown clip will fit into either side of it anyway. Nonetheless, the “normal” version is available for those with SLA / SLS printers, or who want a more normal-looking piece.</p><p>FreeCAD files for both both versions are included. Please do not sell this model without contacting me first.</p><h3>Printing</h3><ul><li>Rafts: no</li><li>Supports: no (if using the “printable” version, as recommended)</li><li>Infill: 15% (less would likely be fine, but has little benefit for this piece)</li><li>Perimeters: 2</li><li>Layer height: 0.20mm</li><li>Material: PLA (others would likely work)</li><li>Other: I would generally recommend turning on the expert setting “Avoid crossing perimeters”, as it will keep the teeth slightly neater by reducing stringing artifacts from movements between teeth, and has effectively no print time impact.</li></ul>