You can make pcurves from wireframe lying on a surface, within tolerance, or by projecting wireframe onto a surface:
After you have selected Exact, select the wireframe .
Only select a wireframe lying on the surface because any wireframe lying above or below the surface cannot be used to make pcurves with this method.
The pcurves created are only made with the wireframe touching the surface and any part of the wireframe extending beyond the surface is ignored. This is shown below .
The wireframe has not been drawn to show the pcurves more clearly.
Select the wireframe to project onto the surface . You can select any wireframe, regardless of whether it lies on the surface.
The pcurves are created by projecting the wireframe selection onto the surface, along the principal axis . In the example below, the principal axis is in the Z direction.
Select the wireframe to project onto the surface . You can select any wireframe, regardless of whether it lies on the surface.
The pcurves are created by projecting the wireframe selection onto the surface, along the surface normal .
Select the wireframe to project onto the surface . You can select any wireframe, regardless of whether it lies on the surface.
The pcurves are created by projecting the wireframe selection onto the surface, along the view normal . In the example below the view direction is ISO 1.
The pcurves are created.
To create wireframe curves from pcurves: