Gear
Draw a real gear, so two of them turn smoothly instead of nodding through every tooth.
Say the module and the tooth count. Module is tooth size: two gears mesh only if it matches.
The tooth is an involute curve, which is what keeps the ratio constant as the teeth roll past.
Two gears run at the sum of their pitch radii. A 20 and a 40 tooth at module 2 sit 60 mm apart.
Every setting
6What each number in the dialog means, and where it starts.
Tooth size. Two gears mesh only if this matches.
How many. Under about 17 the teeth start to undercut.
20 is standard. Use 14.5 only to match old gears.
Play between teeth. Zero binds once you add kerf.
Centre hole. Zero leaves it solid.
Points along each tooth flank.
What it is
Draws a real involute gear, so two of them turn at a constant ratio instead of nodding through every tooth.