1.To facilitate clamping. The prototype's structure should facilitate the positioning and clamping
when processing,less clamping times. Use the top clamping and lathe dog, but the structure is
not convenient to clamping. You can easily device the holder.
2.To facilitate processing. The prototype structure should adopt the standard numercial value as
far as possile,so that can use the standard tools,at the same time,should pay more attention on
the knife and feed back, easy to guarantee the machining accuracy,reduce the machining area
and hard processing surface, etc.
3.To facilitate the CNC machine programming
