mdsSpurGear

Simple OpenSCAD script for parametric involute spur gear generation.

Based on Boston Gear design rules https://www.bostongear.com/pdf/gear_theory.pdf

The script has several customizable parameterization options including:

  1. Number of teeth
  2. Diametral pitch (default is 24)
  3. Pressure angle (default is 20)
  4. Shaft diameter (default is 0.125)
  5. Gear thickness (default is 0.125)
  6. Major holes (default is on)
  7. Minor holes (default is on)
  8. Number of holes (default is 4)
  9. Hub thickness ratio (default is 1.0 which means no hub)
  10. Smooth teeth (Experimental so default is off)

Example images of various gears

24 tooth gear

24 tooth gear, 24 diametral pitch, major holes enabled

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24 tooth gear, 24 diametral pitch, major and minor holes enabled

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48 tooth gear, 24 diametral pitch, major and minor holes enabled

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10 tooth gear stacked on a 48 tooth gear, 24 diametral pitch, major and minor holes enabled

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2D Projection of a 24 tooth gear, 24 diametral pitch, major and minor holes enabled

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Collection of gear designs

You can view additional examples at Thingiverse.com

Release Notes

  1. If you use a hub thickness ratio of greater than 1.0 you will need to consider printing with supports.
  2. The new experimental smooth_teeth option generates a bezier curve rather than a simple polygon for the tooth profile.
  3. Unless you need to change the diametral_pitch to match a mating gear the default option is a good choice.
  4. The tooth thickness seems to be incorrect. It appears to be smaller by a few thousandths, investigating.
  5. Added !OpenSCAD comment for OpenJSCAD compat