Hi Lordfox, it would be helpful if you could post a 3DM model file of what you show there instead of only a screenshot. That would make it possible for someone to work with your current model and show some ideas on what to do. Right now without the model posted if someone wants to show you something they have to create it all from scratch, so that may cut down on the number of useful replies to you.

But as far as removing a hard seam, the main ways to do that are either with Fillet or Blend.

To use Fillet you select the edge where those pieces are joined and run Construct > Fillet. Blend is a little different, Blend creates a new surface in between 2 edges so for Blend you need to leave some empty space between the parts and then use Blend to fill in a smooth connecting piece.

But Fillet or Blend are the tools in Moi that maintain smoothness to the surfaces around them - Loft or Sweep do not do that.

- Michael