I need help!
 
Let's say i have an expansion valve drawing. I draw a 3D model but i want to make different copies with different top and bottom radius. Is there any way for me to just type a new radius and the model automatically changes itself? I hope somebody can help me with this.
 
Thank you.

Not in AutoCAD - you will need Autodesk Inventor for parametric 3D models and assemblies.