Parametric OpenSCAD Clock Gear Train (Hours, Minutes & Seconds)

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The original Proof of Concept for the printable clock has been expanded to incorporate the entire gear train using eight pinion wheels. Four of these are utilized to decrease from the escapement/seconds wheel to the minutes wheel, while the other four are employed for the hour wheel (5,3,2,2). Implementing higher gear ratios with two pinion wheels would be challenging, and three would cause the minute hand to move counter-clockwise. The OpenSCAD script was designed to ensure that all gears are equidistant by adjusting tooth size pair by pair, and allows for bending at each wheel to stack second, minute, and hour hands together. It's fully parametric, allowing customization of distance, fold angle, gear ratios, and number of teeth for each wheel. Additionally, the gear train can be animated with all gears rotating at correct speeds and meshing. While recursion is not supported in OpenSCAD, various configurations can be experimented with using the script. For instance, setting the fold angle to zero creates a long clock layout, removing first two gears with adjusted ratios of 5,4, and a 120-degree fold angle results in a triangular clock with a retrograde minute hand, and removing the first four gears with ratios of 8 & 7.5 and a 180-degree fold angle produces a more typical two-arbor clock. Processing time for the eight wheel gear train on a two-year-old Thinkpad is approximately 12 minutes.