Michael Chiu : German Equatorial Mount

In order to image deep space objects, a system must be used to compensate for the rotation of the Earth so that the object in question appears to remain stationary relative to the camera. There are several ways to achieve this, one such being the German Equatorial Mount. By aligning the major axis of the mount to Polaris and rotating the camera along this axis at a rate of 360 degress/24 hours, the camera remains stationary relative to the sky, thus allowing long exposure photography of celestial objects.

This design is constructed of .25in laser-cut delrin. All bodies are assembled using t-slot screws. The t-slots are sized for #4 screws such that a #4 nut will sit snugly in a slot, even without a screw providing tension. This makes assembly and disassembly much easier compared to typical t-slots. In addition, the planetary gearbox uses involute gears. The actual models of the gears have an expanded profile. Thus, when the gears are cut on the laser, the kerf of the laser will be compensated for, resulting in perfect involute gears.

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