SP10 and SP11: Crazy Gear Desk Clocks

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Two new clocks in the series called "Crazy Gear Desk Clocks". They have a new gear profile and a layer of gears that are always in motion.

 

SP10 is the medium size clock at 11.75"x12.75" (300x235mm). The total print time on a Prusa MK3S is around 74 hours using 0.8kg of PLA.

 

SP11 is the larger clock at 14.75" x 15.0" (375x380mm). It prints in around 80 hours on a Prusa MK3S using 0.9kg of PLA.

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Their features are similar enough that they can share the assembly guide. Both clocks can be printed on a Prusa Mini or any machine with a 175x175mm print area. Total print time 

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The clock was designed using the following criteria:

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1) The clock needs to look good. The new gear profile looks amazing with all the extra dynamic motion. The gears were extended beyond the frame in a nice symmetrical pattern.

2) It must be accurate. The DS3231 precision real time reference clock has internal temperature and voltage compensation to stay hold an accuracy of about a minute per year. The algorithm is self-calibrating to lock the sweep second hand to the real time within a fraction of a second.

3) It must be silent. The TMC2208 stepper motor driver runs incredibly smooth and silent.

4) It must use standard components. All of the electrical components are readily available on Amazon or equivalent source.

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The dial is available with either a solid easy to read face or an open face for better visibility of the moving gears. Both Roman numerals and simple numbers are provided.

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Two different methods of driving the clock are described in the assembly guide. The cheapest method uses a CNC Shield V4 control board with a few jumper wires to connect the components. A more elegant solution is the Silent Shield Clock Controller on Etsy that provides the minimum functionality needed to drive the clock. It is available in kit form, partially assembled, or fully assembled and programmed.​