Blending issue

Rhino Rhino for Mac
1

Anyone have an explanation or remedy for this? All edges of the blended surface were matched. There’s enough structure to accomodate tangential joints and yet I get the anomoly shown.

BlendingThing.3dm.zip (711.9 KB)

Capto_2016-06-11_03-07-47_PM.png1564×1121 465 KB

2

Yep, it is tangent. But that in itself does not guarantee it will look nice… The tangent direction on the upper surface dives just inside of the tangents of the vertical surface so the blend has to have a reverse in it, a slight ‘s’ shape. Ideally that surface would be completely convex in section.

-Pascal

3

I’m trying to tweek the control points on the upper surface but it doesn’t seem that history will updage the blend. Is there some way to make this blend in real time? If not, how would you recommend I proceed?

4

But it isn’t and it been a full day now of trying to make this happen. I’m really stuck here. I’ve widened the gap to fill, I’ve tweeked the control points on both surfaces, I’ve remade the entire surfaces several times and there’s no getting around this problem. Maybe it’s physics. But I can’t understand why this is such a issue.

I’ve tried to make adjustments in the rendered mode but the highligeted points and isocurves make it impossible to judge.

WTF?

BlendingThing.3dm (743.1 KB)

Capto_2016-06-12_03-55-42_PM.png1468×956 120 KB
Capto_2016-06-12_03-56-00_PM.png1468×956 212 KB

5

Use the section command and section both surfaces to be blent at several points (specially where you are having trouble). Then use the line blend command (or adjustable curve blend or yet arc blend depending on the expected result) to connect (blend) the curves. Use the borders of the surfaces (to be blent) plus the blending curves you’ve got and make a surface using Surface From Network of Curves Command to draw the surface you need. In this way you have fun control of it. Hope it is helpful.

6

Thanks for the advice Aldo.

I’ll return to this as it’s a source of unease for me. I set that aside and I’m presently I’m dealing with another item that’s stretching my skills.

Capto_2016-06-22_04-38-46_PM.png1018×1121 145 KB
Capto_2016-06-22_09-18-12_AM2.png1228×1326 359 KB

I can’t quite get these surfaces to transition smoothly.

7

You have a “zero degree corner” where two edges of a surface are tangent where the meet at a corner. That frequently causes problems of various sorts including extending surfaces and matching or blending another surface to an edge.

Two possible alternatives:

  1. Model the surface so that it has an overhanging corner and then trim to the desired shape

  2. Divide the surface into several surfaces.