tarmo4 open diff spider gears, with axle options

youmagine

Spider gears crafted from OpenSCAD script https://www.thingiverse.com/thing:1588376, measurements taken directly from photos of gears, and revised after thorough printing tests. Still refining this project, but now these gears mesh fairly well. However, I don't yet have the bearings to fix the parts, so further revisions are on hold. Currently, consider this design incompatible with 3D printed gears due to their tiny size and excessive friction - at least in PLA - which leads to heat buildup. I plan to try printing in Armadillo and CF nylon once my car is up and running. The spider axle gear comes with two separate axles (3mm hole as original, and 2mm hole for a 1.75mm paperclip). Important: when importing into your slicer program, ensure Autocentering is OFF. Group the axle only and spider gear axle before moving to maintain their origins. Depending on your slicer, you may need to separate surfaces, heal mesh, or take other corrective actions as there are two intersecting volumes that some slicers don't handle well and can result in printing air. Part 14A was also adjusted by adding 0.5mm to both the inside and outside dimensions, as there was approximately 1mm play on this side of the diff that prevented correct meshing, and also from the original plans seemed to require an additional 0.5mm on this bell to correctly align with gearbox housing 03A. https://www.reddit.com/r/EngineeringNS/comments/g1dat8/tarmo_4_almost_done_but_i_have_a_strange_issue/fnn874e/