Surface continuity approach while keeping surfaces as simple as possible

Hi. I am trying to design the housing of a desktop, somewhat similar to the Alienware aurora r12 desktop, as a surfacing practice.

I want to use edge surfaces as much as possible, keeping the degree low and then trim when necessary, match surfaces and increase degree if required to close everything up, the goal is 0.2-0.3 tangency.
I’m not sure how to approach it in a clean way, these are some attempts.

The issue is, either a 5 edge hole or a singularity at a vertex of adjacent surfaces with different isocurve direction.

Hope you can help me . I can also provide the file in case you need it.


In as few words as I can, defining everything by edge curves is not any kind of ideal NURBS modeling.

“Trimming” is NURBS’ killer feature, you need to use that.

Most “5-sided hole” problems go away once you see the model as a series of intersecting basic shapes that extend beyond the bounds of the finished model that are trimmed and blended together.

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I come from a solidworks background, so I’m far from mastering Rhinoceros. For me it seems that surface from edge curves allows sculpting due to less control point density and overall better continuity results when combined with “match surface”. Wouldn’t that be the approach used on the left side image? The right side was a blend surface I did between the handle and the remaining basic shape. Even though I wasn’t trying to achieve the same result, I don’t think the outcome would be comparable if I did, using trim and blend. This is a series where it explains the benefits of edge surfacing: Primary Surfacing: Episode 1 - Intro - YouTube There’s some interesting examples where he achieves very low tolerances for tangency and curvature whilst having some sculpting control during the process.

The image on the left is also very simply a handle blended to a body shape. They’re the same thing with slightly different parameters.

If I didn’t like the blend result I got (actually that was made with the ‘blend’ version of filletsrf) I might rebuild the blend as something I can tweak by hand, or manually trim out the edges to BlendSrf, or any of another dozen things. I don’t know how you would expect to make that any “simpler” as a series of edge surfaces, nevermind smoother.

I made some Rhino surfacing tutorials myself back in the day, Hydraulic Design Rhino Sales and Industrial Design . At this point many years later it’s been distilled down to, I barely draw curves, I just start placing planes for major features and point-pushing them like I’m trying to fabricate it out of super-stretchy sheetmetal.