I was modeling a chess set. Bishop was my biggest problem. The slice looks ok without a subsurf. Add a subsurf of 2 and ugliness happens.
I went to just practicing on a cylinder. looks ok, but I'm still get creases/folds. I get the slice by beveling a flat cube and booleaning.
So far this is the best I can get.
Thanks for any help or suggestions. Just another noob wading neck deep in blender water.
Not sure if my solution is a perfect as I would like, but here is what I ended up with.
I removed the edges inside the slice and allowed the Subsurf to create the curve. That eliminated the mega ngons that was being created.



