Sep 272020

Version 2.0 of my online involute spur builder is available now: Online Involute Spur Gear Builder v2. It is a complete rewrite of version 1 which was introduced 2014 (part1, part 2).

Version 2 creates higher quality output without ragged edges at higher speed. Like before, undercuts as needed for small tooth counts are correctly handled; clearance, backlash, and profile shift are fully supported.

As an extreme case the image on the left shows a 12 tooth gear meshing with a 5 tooth pinion (tool link). Notice the extent of the undercut. The image on the right (tool link) shows the same gears but this time with profile shift applied. The profile shift considerably strengthens the pinion gear teeth.

Without profile shift Involute gears with undercut and profile shift.

The key differences of v2 compared to v1 are:

  • Modern SVG output
  • Higher quality output (no ragged edges) without excessive segment counts. No more need to fiddle with quality parameters.
  • Significantly faster than v1 at any acceptable quality levels
  • Parameters are automatically injected in the URL; i.e., the URL fully specifies the output and can be shared with others.
  • Corrected internal gear generation (e.g., clearance is properly applied)

In case you are interested in how the gear shapes are created, the first post that introduced version 1 is a good start. Then this pdf document provides more detail about how v2 accomplishes the smooth curves that v1 struggled with. Internal gears are particularly challenging in this regard. Here is just a teaser:

Internal Gear Shape Creation