Unfold Polysurfaces

UNFOLD A POLYsurface
I have problems deploying polysurfaces, since I do it with the deploy command and it doesn’t usually give me very good results, I need it to generate flat parts from a mold which I pass to a 2D cutting machine to then cut pre-preg material and paste it by layers in the physical mold.

What would be the best way to do this process?

What is the Deploy command? Either a plugin or something got lost in translation, as it’s not a Rhino command. Also, what is it you are trying to unfold/unroll? Are they planar, single or double curvature? Best would be to post a simple Rhino file showing what you need help with and a clear description of your problem.
HTH, Jakob

The command in inglish is Smash, Sorry for de translaton.
The problem is that when using smash it generates a surface in broken pups that when I later make a 2D of the cut the distance of the surface does not correspond to the distance of the flaten surface, causing the development of the piece to be incorrect.

Ejemplo_Capot.3dm (3.2 MB)


A curved surface needs to be “developable” to unroll without distortion. That is how geometry works. Some the surfaces in your model are not developable.

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As had been said nothing about that is “developable,” the whole ‘devleopable surface’ thing is meant for skinning the hulls of enormous ships, not this.

Determining the flat pattern to start with to form this requires either extremely specialized, expensive software–if it exists, I have no idea, I’m just guessing–or real-world trial-and-error using the Mark 1 Eyeball.

It seems it might be possible to remove various features and simplify things to get to a developable starting point for your 2D, but no there’s no magic button to push.

“Developable” is a geometric concept, not size dependent. If a surface is developable it can be unrolled to flat without any stretching, shrinking or shearing. If the surface is not developable then flattening the surface will require some combination of stretching, shrinking and shearing.

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I mean sure, but making ship hulls is literally the reason it’s available as a feature in Rhino.

The point is none of Rhino’s “unrolling” features have anything practically to do with forming carbon panels in a mold, it’s a waste of time even trying. From the looks of what is shown you just take the outer perimeter and add some offset, and test it. There’s no magical button, even if you have all the resources in the world there appears to only be FEA simulation to try to figure out if your prepreg will work.

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Hi,
I developed a solution specifically for Yacht Production Eng.

This includes curved parts, flat parts and so on, with marking lines names block name ship name and so on. Several yachtes have already been built using our solution for nestings, boms and workshop drawings and so on.
Let me know if it could help you.

It’s hard to know how to answer this. Is this for a one-off build or production. Are you expecting a single layer of fabric to span the entire mold or are you going to utilize multiple panels with appropriate overlapping of panels.

Have you tried the Squish command? It should get you close, though probably not perfect. In my experience it is better than smash. I use it all the time for sewn goods patterns and have used if for planning out composites cutting with good success in boat building.
Note that different composite fabrics have different conformability to molds and as a result, will often have to be cut slightly differently no matter what flattening result you get from Rhino or any other software. With a bit of experimentation, Squish will get you as close as possible and you can fine tune the result with a bit of trimming at the time of lay-up. I hope that helps. Cheers.

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