Work in progress upgrading my auto-telescope mini project with 2nd iteration (1st iteration:

3D Printing
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Work in progress upgrading my auto-telescope mini project with 2nd iteration (1st iteration: https://plus.google.com/+SameerAnsariSam/posts/gdmSsvKL78f)

Worm gear design, torque is way lower thanks to worm physics, and 128 teeth theoretically yields 128:1 x200 steps = 25,600:1 gear ratio or = 0.0140625 degrees, with 16x thats ~0.0009 degrees or 3.2 arc seconds

32x could give ~1.6 arc seconds almost reaching the fabled 1 arc second precision which’ll be the goal of 3rd iteration.

The original gear setup had barely a 6:1 ratio x200 steps = 1200:1 gear ratio or 0.3 degree resolution, terribad but fun.
With microstepping could get up to 16x ~ 0.01875 degrees but slipping due to torque happens, 32x microstepping was a no-go.

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can u share SW files?

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@Zviad_Sulaberidze Here is a drive link https://drive.google.com/folderview?id=0BwW6qsUNa47xTF9Yb1k3MHlIY1E&usp=sharing

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many thanks :slight_smile: did you use any gear calculators, or theory? I have in mind to make a gearbox for my robot, but don’t know where to start

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A little theory ~ # teeth on worm gear = gear ratio to worm, made sure to match the pitch. This site gave me a rough idea of how to make a gear http://grabcad.com/questions/tutorial-how-to-model-a-gear-in-solidworks-and-show-design-intent , also designing the worm is really similar to designing a spur, just using a helix as a guide path instead of circular pattern