Below are some screen shots of a Program call SolidWorks. I have used AutoCad for years
but SolidWorks does a great job with Solids and surfaces. Its not easy to unlearn AutoCad
and use somthing else but after about 3 weeks I learned enough to get the new design down.
 

Movie of CNC cutting Small             (~5mb)
Movie of CNC cutting                      (~10mb)
 

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