Extracting sketch data from a scanned real subject in the form of a STL format file.

Dear Solidworkers.

Is there anyway way a Solidworks sketched contour can be extracted from an imported STL file of a scanned subject? ( e.g Car ) so that a solidworks model can be developed from a series of section planes moved along the length of a scanned STL file.

123Dapp.com is a photographic method for producing 3D models from photographs. The output file is an STL file.

I am a model maker and would benefit from having a worked technique for replicating the contours of a scanned model back into Solidworks from scaling and further processing.

SolidworksSurfacing