Images Above; show hybrid modeling process
The Polygon models tolerance is around 6 inches, I delvered a engineering model with .125 tolerance
In order to get a concept or polygon model into manufacturing it will have to be rebuilt into engineering surfaces.
In the hybrid process I build surfaces in engineering data to eliminate the need to rebuild later.
I do use polygon models when the surfaces are not needed down stream, example, the two pilots
At the end of the day it is more cost effective to design and render in engineering surfaces