When you convert surfaces, IDD creates a set of procedural surfaces that replaces the original surfaces. When you convert freeform surfaces that approximate cylinders and planes to analytic cylinders and planes, you can use them as references for component assembly and datum creation. When you convert the surfaces that are already analytically planes and cylinders to procedural planes and cylinders, you can adjust their size or placement, or both. When you convert surfaces to extrusions or revolves, you have full access to the section representing the converted surfaces; this allows for almost unlimited customization of their shape.

Conversion works best when the shape of surfaces selected for conversion closely matches the shape to which you are converting the surfaces. There is no restriction that disallows you from attempting to convert a planar surface to a revolution or cylinder, but the results could be erratic. The intent of the tools is to take surfaces that are a close or even exact match to the form of the selected conversion to allow for expanded modification abilities and or better down-stream usability.