Add thickness to surfaces facing different directions - without creating gaps


I have made this voronoi cylinder from a grasshopper tutorial. I want to add thickness normal to each surface, to make it 3D-printable. When extruding, the surface will “wedge” apart, as their normal direction is not the same. The tutorial I saw suggested “Weaverbird” - unfortunately this not work for Rhino 6.

How can I add thickness and keep edges together? Thanks in advance (8.1 KB)

Can you try scaling it?

  1. Join all meshes.
  2. Remove identical points. Here I use MeshEdit.
  3. Extrude.

The other mesh editing components are from PhylloMachine. (22.5 KB)

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Is it important for your design to follow this method?
by looking at it it seems that it would be far simpler to create the voronoi surface on a planar surface, extrude it and then use surface morph to morph it on a cylindrical surface.
(you can make sure there will be no seam by using identical points on the two sides of the original surface and cut what’s left)

I believe this is what Aris is referring too:

The difference is that here you conserve the circular nature of cylinder with the Voronoi.
But I find the meeting of the geometry to be disturbing. (you can notice in it in the picture attached). I do not know how this could be solved for now.

This is what I’m talking about.
(if you repeat the points left and right and then trim, you will have a ‘seamless’ pattern.)
unfortunatelly, I am a little buffled with the intersections. Differences (for me at least) have always been a difficult part.
The final extrusion is not a clean shape and thus the final morph looks good but is not a good solid.
Maybe one of you guys can help with this part?
(@Joseph_Oster, I’ve kept it ‘telepathy-free’ in case you want to have a look at it) :slight_smile: (25.0 KB)

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:scream: :scream: :scream: :scream:
It was so easy???
edit: (I see now the cells are not prismatic, but you can intersect with the surface and extrude)

Same approach + some modifications… (16.6 KB)


Here are two related approaches - NEITHER of which require any booleaning, so should be significantly faster.

This one builds on your existing approach: (12.7 KB)

And this one skips the need for the 3d voronoi. You can successfully solve this and maintain tiling
with a 2d voronoi, as others have pointed out.
Voronoi (16.1 KB)


Thank you guys for some really good inputs and suggestions! I appreciate the solutions and alternative approaches to my little project here.
I have now used Joseph_Osters simple solution to make a model for printing - will post a pic if it turns out well.

My next steps is to try to make the shape more organic by filleting the edges, and eventually see if I can make some alternating structural thicknesses. I will be happy to hear your suggestions in this regard.

Another approach for these “Organic Cell” type shapes, is to look at manipulating/utilizing mesh edges. There are two plugins that open up some really interesting form explorations: (three actually…)
Weaverbird, (almost a requirement if you are doing any work with meshes…IMHO).
CytoSkeleton : Cytoskeleton - Grasshopper
Kangaroo, (one or two): In addition to the physics simulation, (which is not being utilized in this example), there are some very handy mesh editing/cleanup utilities. In this case, it’s just remove duplicate lines

There is some great discussion and examples on the old GH forum for using CytoSkeleton. Exoskeleton is another one.

Attribution: It would be remiss to not acknowledge Nervous system, whom brought this form into fashion back in 2009. Cell Cycle: 3d-printable jewelry design app inspired by microscopic cellular structures

Plugins required for example file:
Kangaroo (version 1…or 2, I just used the remove duplicate lines component).

Example file created with Rhino 6/GH 1.0.0005 (22.4 KB)

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Here’s a different/simpler approach that might be helpful for you. (26.0 KB)

I’ve printed a lot of things like this. You have to be careful about the horizontal parts since there is no support for them. It’s a good idea to do a bridge test with your printer so you know how far it can span without drooping or messing up.

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HI all,

i was playing around with something like that, the mesh version.
It fails at some points, maybe someone knows why? (11.4 KB)