Hi Rob,

> I guess its a bit of an awkward shape but annoying all the same
> as I would have thought this type of work would be where moi/nurbs
> would come into its own without resorting to work arounds.

It's not an uncommon problem when you are trying to have multiple different shapes kind of "forced" to collapse together into a single point.

Things will tend to kind of stretch at different rates and kind of twist...

If you have things twisting and collapsing, that just does not tend to make good geometry.

Here's a screenshot of the control points for your original shape:



You can kind of get a sense there where different shapes (the sides versus the less curved spine) are all trying to come together but at the sides are trying to cover a larger distance and rushing together kind of faster, making bunched points, etc...

> would be where moi/nurbs would come into its own
> without resorting to work arounds.

It just does not physically or geometrically work very well to try and force different shapes to suddenly touch one another.

It's kind of similar to if you were to try and build that thing out of 3 equal lengths of wire - the curved ones follow a much longer perimeter than the central one, so there is not really anywhere to put the extra length of the central one, it would get all bunched up.

When you're using a surfacing command like sweep or network, things are connected together between profiles in a more equal way similar to that, when the shapes are far from equal that will be a bad matchup.

Remember NURBS are not magic - they work within a certain framework especially individual surfacing commands.

- Michael