Is there a way to add a lip to a thickened surface model?

[nweston]

So I'm creating a USB case for an assignment and I'm currently attempting to add a uniform lip to the various parts so they can slot together. I did the front edge by just extruding a cut away but the top edge can't be done this way as it curves in different planes. Any suggestions?

[DeanLong]

VSS or Swept Blend will work.

Offset surfaces will work too.

[WayneN]

I would make the lip before thickening the part. Use the edge of an offset surface for a trajectory and create a variable section sweep that uses it. Or maybe add curves connecting the edge to the existing surface (like a ladder) and use a blend. In both cases the surfaces would have to be merged before thickening. It's been a while since I used surfaces, so there is probably an easier way.