In the past, it has been a bother to make proper involute gear teeth on the fly.
I have therefore resorted to "perfect mesh" cylindrical teeth in my gear sets for CAD purposes.
For some reason, these are not practical in the real world, but in CAD, they are easy to manage.
...until I tried a bevel gear, that is.
Rather than get into a long conversation about how the geometry is defined, I opted to provide the model and let you take a look for yourself.
Please post comments as questions arise and I will reply in the comments below.
The attached ZIP file has the appropriate assembly, part model, animation file, and mechanism file.
click on the small image to start the animation
Enjoy.