Hi Luis,

> Here is the result using cover surface tool on sharfx to make a cover on the hole (I think viacad also have this one)

This one I think is definitely better than the previous one that came straight from filleting - this one is both lighter in control point count and also "stiffer" with less lumpiness to it.

That's very interesting that it's fairly different from the one that comes from filleting. I wonder if it's actually using a different mechanism for generating the surface or whether it's just a different set of parameters for the surface generation...

It instead though has a different problem where it's noticeably not G1 to much of the boundary areas though, note the sharp creases in these areas:



- Michael