By seashell I mean a shape like the above. It has me stumped because the underlying shape has smooth curves in all three axes, and the grooves all extend from the center (but in fusion we can only sketch on flat planes).
I tried using the sculpt workspace but didn't make much headway. I had some success sketching the perimeter and using a loft but I feel I'm approaching it wrong. I would be very grateful if someone were to show me the best practice on how to do it.
For closing the structure you can use the bridge function.
To create the flat bottom I selected the lower edges and extruded them out some and then used the flatten function and then simply extruded out the sides. Then it was a little tucking a puling around on vertices here and there.
Make sure you look at your models often in box mode. It is easy to create geometry that looks fine in smooth mode, but contorted in box mode. If it looks good in box mode and approximates the shape you are looking for all enough usually it will also look great in smooth mode.
Second screencast below:
One thing to keep in mind that with T-Splines you rarely have to "throw away" geometry. With normal parametric surfacing or solid modeling approaches often it s the initial approach that backs you into a corner and yu might abandon it and start fromm scratch.
With T-Splines you might delete some faces but the amount of re-use is higher.
I personally try to stay away from finishing a T-Spline with surfacing tools.
If I can completely model something as a T-Spline I'll do it.
When completing things with surfacing tools you you usually end up with sharp edges and then feel tempted to fillet =those edges. However, T-Spline create complex surfaces and the filleting algorithm in Fusion 360 often fails to fillet.
Also T-SPlines are naturally G2 curvature continuous and often in my work I am interested in surface quality.
