Surface flattening

I want to flatten the attached surface. Rhino asks for curves to select. I made the shape with a boolean and not by trimming. Therefore i cannot selct curves and the surface does not develop.
What am i missing here?

regards, René

Sorry, i forgot to attach the surface.bovenligger cut.3dm (631.8 KB)

Sorry, I’m not clear what are you trying to achieve, do you mean unrolling a surface?

If you want to unroll just the polysurface, forget about the curves.

However, let’s say you want to unroll a curve which is on your base polysurface, then select those curves…

If you want to unroll the curves along the creases of your polysurface together with your surface, you can select those with a click while holding CTRL+SHIFT.

I just want to unroll the surface but if i ignore the curves it does not unroll. Does it work on your side?

Hi @rene1
This might sound dumb, but the unrolled surfaces are made at the world origin at 0,0,0 - just to make sure that they’re not “lost”. If that’s not it, are you getting any feedback/error from the command prompt?
HTH, Jakob

Yes it works, but as one of the comments states, the unrolled surface is at 0/0/0

Aha! enlighted! Found it. Thanks a lot guys. Going to feel dumb for a while.