Generate sketch from flat object outline

If I bring a step file into S3D of a flat surfaced rectangular object with cavities and then create a rectangle solid object in S3D and do a subtract to end up with solid bodies in S3D of the cavities. I then want to select the top flat surface outline to generate a sketch to work from. I have to go around the entire outline shape drawing lines from the outline edge to get it to individually fill in a sketch line of the edge. Afterwards I need to then go back and trim every intersecting line I drew to end up with only the outline sketch. Is there a simpler way to achieve this result from an import of a step file? It would seem that it would be easy enough to automate as it seems to be able to be done manually although manually it is a very slow tedious process. Thanks

Use the Project tool.


Thanks that works perfectly. Great help.