This is a spur and helix/herringbone gear generator which allows you to change tooth dimensions, number of teeth, gear thickness and more. Feel free to change it up or add your own aesthetic elements. If you don't have OpenSCAD to edit the gear dimensions, it's free to download and even easier to use. It's worth the trouble if you want to build your own custom gears.I have always wanted to build a spur gear generator, but have never figured out how actual gear dimensions were determined. I finally started drawing up sketches on paper, and from there I noticed some mathematical patterns. Using the geometrical patterns, I was able to develop some formulas that would take the base length, top length, and height of a tooth and turn it into useable gear dimensions with any number of teeth. It was very satisfying to "re-invent the gear." Update: Now includes ability to make Helix and Double Helix gears! Version 2.0 has this functionality.