After creating wireframe entities in the graphics area, you can select the curves and use them to create splines with any of the three Spline functions: Approximated, Interpolated, or Fit.
1 After creating wireframe chains, enable selection mode and click to select the desired chains.
This may be open or closed chains, and you can click, drag a window, or hold Shift and click to chain select all curves that you want to use.
2 In the Splines menu, click Approximated, Interpolated, or Fit.
3 A spline entity is created from each curve that you selected.
The original wireframe remains in the graphics area and each spline curve is created as a new entity on the active layer.
4 To close the Data Entry Manager, click Cancel.