Give a NURBS Surface curve hard edges?

I’m modeling a boat hull with NURBS Suface curves. My trouble is that the hull in question has some sharp edges which seem impossible to contour with these curves. Is there a way to give them sharp angles?

under edit window
when in edit mode on nurbs
select the edge you want to be sharp
on the curve tools node change weight to 100 and hit set weight

Perfect, thank you.