Merging surface of shell or solid without affecting its shape

[emirudlari]

Hello, I designed this bowl which was sliced for a long time ago by using different cam software.  Now I want to change its shape and number of slices. but first I need to have one piece bowl. I tried a lot of things. 

1. I stitched all part and merged them but its shape was altered.

2. I cut a piece of a solid body by using this bowl but same traces came to the surface of the solid, Merged and shape was altered again.

3. I tried to draw again it by using the loft comment, I split the surface, get intersection lines but split lines make a big problem with loft comment. I couldn't merge split lines and I drew splines on their trace but the loft comment didn't work.

Please give me an advice,  thanks, Emir

[TrippyLighting]

Can you share the original model (attach to next post ) and then explain what you wan to do with it or in what ways you want to change the shape ?

[emirudlari]

Thank you, I added the file. As you can see the model consists of 25 pieces (ribs). Actually, I want to change dimensions and number of ribs of the bowl and I offset surface and make solid from the shell.  Of course, I can scale the current model, maybe offset and make solid but I can't change the number of ribs. For example, I need to divide it into 21 pieces for my new project and if I divide the current model again, there will be a lot of lines, so I want to make this bowl as a one-piece shell by guarantee exact geometry, then I can divide it the different number of ribs I want. Actually, I produce this bowl by using woods strips so ribs number and dimensions are very important for me. I cut woods as a ribs dimensions. Best.

[mavigogun]

So.... you want to recreate the gross geometry of the entire form as though a single surface?    What exactly does "precise" mean to you in this context?

[mavigogun]

First, the model has some compelling issues- here:

All these crossing surfaces- they don't make me happy.   I doubt they'll make Fusion happy.    I won't confront that issue.    As to recreating the form, I:

• turned on Capture Design History
• parsed out all the interstitial ribs
• Projected the leading edge to Sketch
• placed a Line along the center Axis
• Created Form
• Revolved the Sketch Profile with 8 and 23 faces to 180 degrees

Now the Edges and Vertices of the T-Splines may either be Matched or Pulled to the nearest corresponding Edge or Point on the corresponding surface slice.    There's plenty more work to be done- but that's how I would start... well, after resolving those crossing surfaces, anyway, as they are going to present some grim results and serious challenges to this scheme.

[TrippyLighting]

I looked at the model you posted and I m wondering what thought process went into it and what the end goal of it is.

All these slices seem to serve very little purpose, at least from a pure modeling standpoint.

Can you share more details about what you are going to do with the model ?

[mavigogun]

I produce this bowl by using woods strips so ribs number and dimensions are very important for me. I cut woods as a ribs dimensions.

Sounds like templates for sections; I, too, would very much like to hear how the sections are translated to patterns.  Actually, some constructions photos would be awesome!

(What was that "different cam software", anyway?)

[TrippyLighting]

I went back and looked into the OP's earlier threads. As it appears this is going to be a musical instrument.

That also makes the construction process more understandable.

Either way, the initial CAD model does not make reconstruction easy as the cut lines for these slivers are not straight surfaces. I am wondering if this was done intentionally if this was simply a CAD mistake.

[mavigogun]

A bit of visual explanation here, me thinks:

https://www.google.com/search?q=laminate+lute&safe=off&client=firefox-b-1&tbm=isch&tbs=rimg:Cfh598ix...

Or, more specifically, an Ud-

https://en.wikipedia.org/wiki/Oud

or Bağlama-

https://en.wikipedia.org/wiki/Ba%C4%9Flama

(Selam, Emir.  Ailemden bazıları Develi'den.  Mavigogun = "mavi gögün". Maalesef, küçük bir çocuk gibi Türkçe konuşuyorum.)

[emirudlari]

Thanks alot, yes I am a luthier. Especially I make ouds. I drew my first model by using Rhino. I modeled it from real oud. Then I cut model with plane array. After that I unwrap rips and use them as a template to cut wood strips. Then I bend and sand them and glue together on a mold. 

(merhaba mavigogun çok memnun oldum görüşmek üzere) 

[mavigogun]

Beautiful work!   Unfortunately, Fusion doesn't feature a wrap or unwrap tool; the service ExactFlat is a common recourse.

https://apps.autodesk.com/FUSION/en/Detail/Index?id=3499335255055878377&appLang=en&os=Win64&autostar...


https://www.exactflat.com/online

[TrippyLighting]

The unwrapping can also be done with Meshmixer withe night precision for this project.

[mavigogun]

I exported a section at low resolution, Unwrapped it with Meshmixer, brought it back into Fusion; the Edge Loop length differs by as much as a centimeter.   I'll experiment some more when I have time.

[TrippyLighting]

When you do, change the aspect ratio. The default is 21 which can create triangles that are very long.

[emirudlari]

thanks, actually I tried to use loft comment again. to find the exact intersection point of profiles and rails line used intersect comment on the interested plane. The loft is ok between profile but when I try to add rails it gives an error. I don't understand why it happened. I am trying to use Fusion 360 for a long time because I am a lecturer as well and I want to design instruments with my students but it is very hard to make easy something. I hope I can solve, best

[TrippyLighting]

First of all : Beautiful work!

This is not at all a trivial thing to do either with real materials, or in CAD

I created a lofted body by first project/intersect some of the profiles into sketches.

Then. I traces those sketches with splines using the least amount of spline control points. This creates better curvature and is MUCH easier to edit. Without knowing the initial construction method in Rhino this can only be an approximation but it should be close enough.

Go through this and ask questions if you don't understand a step. Then we can move forward from there and consider next steps.