Hi Nick, you should be able to select and then delete the curve that you used to create a revolve.

If you're having a problem with this, maybe you can post a .3dm example file? That would help me figure out what is going on in your case.

After you have created a revolve, there is a natural part of the revolved surface that looks really similar to the initial creating curve - that is the "seam edge" of the revolve.

Surfaces in MoI are in a certain sense like a rectangular sheet of paper. When you create a revolve it will create a surface that is configured similar to taking a sheet of paper and rolling it into a tube, so that 2 edges of the paper are now touching each other. That touching edge is the "seam edge" of the revolve and you can't delete that part, it is a built in part of the surface's trimming boundary.

- Michael