there is less "math" than you think....
No algebra or geometry in this case. Imagine concentric circles where the small one is your template and the large one is the guide bushing traveling around the outside of the small one. It will create a larger radius.
If you use the female template, you make the template's radius the size that you want it to be when finished. You then use a "flush trim bit" which has a bearing on the top that is the same size/diameter as the cutter. When you follow/trace the template with the bearing it will cut the same radius below.
The answer to your question will only be as detailed and specific as the question is detailed and specific. Good questions also include a sketch or a photo that illustrates your issue. (:< D)
Last edited by woodnthings; 08-24-2017 at 05:58 PM.