I was trained as industrial designer and my teach in mechanical drawing was kinda retarded and basically barely taught anything. So I never got to learn how to accurately calculate gears. I know there is a difference between gears in 3d and actual gears in real life they must be recalculated more accurately.

Heres the problem I faced over and over and over again. I need to understand how to calculate gears in a given space and I need some detailed expamples so I can understand.

Lets say I have a a center distance of X and need to two gears same gear ratio to transfer power. Spur Gears. How do I figure out tooth size number of teeth diameters and all the other stuff?

and if I have a given ratio say two gears with gear i A number of teeth gear two B number of teeth how do I figure out the rest?

I know how to calculate the involute curve but my problem is figuring out from scratch base circle, pitch circle, diametral pitch etc. I need to be able to calculate from scratch everything.

Say I have a 3d model and I need to convert motion and I have two gears with given number of teeth and center to denter how do I figure out the rest and all other scenarious. I have solidworks 2011 I understand 2012 has gears but I also want to learn this myself. I