EDIT: (looks like you've got it figured out? I had prepared this reply for you anyway, so here it is..)
Hi Steve, at first glance it wasn't really clear to me what you're trying to do there - it's a kind of sparse set of curves.
It seems like maybe you're trying to do too much all in one single surfacing pass rather than building some pieces incrementally?
If you've got areas of a shape that look like they are carved off from a bigger block like it sort of looks like you want to have in this case with the slanted upper and lower pieces, it can be easiest to actually build them in that exact way by drawing a starting block shape and then cutting that with booleans.
Usually when you see some kind of broad flat piece, you can get that the easiest by cutting a shape by a side profile.
Just in general I'd recommend thinking a bit more "2D"-ish - if your shape can be formed by some combination of cuts of 2D profile curves then usually doing it by using those 2D profile curves is the best way.
That would go something like this - start with an initial profile that then gets extruded to form the base block like so:
Then draw in some 2D side profile curves something like this:
Now you can select the block and then use boolean difference with the 2D curves as the cutting objects to do this:
Delete the pieces you don't want, and that will leave you with this:
Then select these edges:
And apply a fillet to round them:
So basically the key thing here is to try and focus more on what kind of 2D profiles can be used to generate the shape and then draw in those 2D curves rather than focusing too much on building a whole 3D curve framework only.
There are some situations where you may need to build a 3D curve framework and do stuff like sweeps and networks for totally freeform type shapes that don't really have any 2D defined nature to them at all, but if your shape does have 2D silhouettes to it, then forming it with 2D curves tends to be better.
- Michael
