Adding a flange plate to a curved surface.

 From:  Michael Gibson
9654.8 In reply to 9654.4 
Hi Gordo, there is also additionally a bit too much of a gap between the surfaces in this area:





That's a little more than a 0.005 unit gap between there, and that's just very slightly more than the join tolerance. Join will only join pieces that are less than 0.005 units apart from each other.

The rounded surface might be good to build differently, if you turn on its surface control points you can see they are pretty slanted in some areas:





- Michael