This is a simple little tool that will help you plan the stems weights values across a 9 styles family.
Input your thinnest and boldest stems values, and it will show you a wide range of possibilities to get you started.
The first column will provide steps of equal size.
The last column will provide progressive steps.
The 3 columns in the middle will provide intermediate steps.
You can use this values as a starting point to plan your family.
The final decision, of course, is up to you!http://www.impallari.com/familysteps/