UnRoll entire surface on Rhino?

Pavilion.3dm (4.3 MB)

Q1: Is it possible to UnRoll the blue object so that I have 3 surfaces instead of 9? Or can I unroll it into 1 entire flat surface?

Q2: If the only way to UnRoll it is in 9 pieces, I want the “pipes” (lavender layer), to meet/connect at each edge of a surface. Is there a way of insuring they connect before I FlowAlongSrf? Or if I have to FlowAlongSrf first, how can I then get them to connect when the edges meet?

Thanks in advance!

Unroll with Explode=No

Might need to explode first then joinedge where you want the folds.

When I UnRoll with Explode=No, I get this… It just flattens it.

I tried but it doesn’t work. Could it be that maybe JoinEdge only works for curved? I created pipes from the curves instead.

I don’t think you’re going to be able to unroll that into one piece because there are concave corners. The pink edges in image below are unjoined edges, so the part unfolds along the blue (joined edges). The unrolled shape has lots of overlaps due to the concave folded edges. There might be a series of folds that can produce the part from one piece, but you’ll have to play around with which edges need to be joined.

If I was making this in metal I would aim for 3 piece with 2 folds each along the top edges.

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woohoo…got it…

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I was also thinking of trying to make it 3 solid surfaces.
The second picture you sent, is that the entire object Unrolled? If it is, how did you do that and how to I form it back again into a 3D shape?

Thank you

Yes, 9 faces unrolled into 1 piece. Explode, joinedge the blue edges from bottom right of image, unrollsrf.

I would still make it as 3 separate pieces folded along the top for physical manufacturing reasons though.

Ok, and if I make it 3 separate pieces, should I do so each piece is on the “long edge” of the object or the “short edge”? I made 3 long surfaces but when I UnrollSrf it still unrolls as 9 pieces, I don’t know how to get it 3 pieces? And lets say I do get it 3 pieces, when I FlowAlongSrf, I’ll still be faced with the problem of the mesh not meeting et the edges.

Several of the surfaces are warped and therefore not exactly developable. The results of UnrollSrf when exploded will have some shrinking/stretching/shearing and have slightly curved edges as a result. The edges of adjoining pieces no longer match.

I know the surfaces are warped and that the edges wont match because of that, I was wondering if there is a way to get the edges to meet.

Too methods to get the edges to meet:

  1. Edit: Does not work for this type of shape.

  2. Rebuild the unrolled surfaces with straight edges. Use Rebuild with degree 1 and 2 points in each direction. The lengths of some edges may then need to be modified so the lengths of adjoining edges are identical. To modify the individual edges turn on control points for the rebuilt flat surfaces and move the control points as needed. Whether these shapes can be used as patterns to build a physical version of the object would depend on the material properties, fabrication techniques, and experience of the person building the object.

Hi Nick - Or…UnjoinEdge =)


Ooohh, didn’t know about that command. Thanks @Pascal.

Another way to analyse it quickly before you decide is to unwrap the shape is as a texture to see how it would look with Rhino doing the legwork for you: