Nice.

I'm an over-40 year old wannabe engineer too, except I didn't get as far as you on my little pet project: designing a 'universal' gear, based on professor Jack Phillips' work "General Spatial Involute Gearing." So far I can model the basic helicoids in Siemens NX, such that they touch along the ISA (Intermediate Screw Axis) which passes through the CDL (Center Distance Line) in between the gear axes. I have no clue how to proceed from there with actual involute teeth.

My idea is to at some point write an NX Open script/module, which takes in various parameters (like selecting the shaft/axes vectors; inputs ratio, pitch, etc.) and spits out something structured like my model.