Sheet Metal Workbench

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Kunda1
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Re: Sheet Metal Workbench

Postby Kunda1 » Fri Oct 25, 2019 3:26 pm

Merged above thread in to this one.
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Fra88
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Re: Sheet Metal Workbench

Postby Fra88 » Thu Dec 19, 2019 5:58 pm

Dear all, good evening.

I'm trying to model the corner fo a Sheet Metal panel and I would like to obtain a semispherical corner.
I made a lot of trials, using also commands from other WB (part, part design,...).
At the end I was able to create the geometry described in the file attached (I used sufaces to create the corner geometry), but unfortunately, is not possible to unfold the panel :cry:

Is there a method to solve this problem?
Thnk you in advance.
Attachments
Model.FCStd
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UR_
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Re: Sheet Metal Workbench

Postby UR_ » Thu Dec 19, 2019 9:16 pm

Undevelopeable faces like spheres can be unwrapped with MeshDesign WB->Unwrap mesh

Screenshot 001.png
Screenshot 001.png (66.73 KiB) Viewed 378 times
Model-unwrapped.FCStd
(580.38 KiB) Downloaded 23 times
Fra88
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Re: Sheet Metal Workbench

Postby Fra88 » Fri Dec 20, 2019 5:54 am

Cool!! What about k_factor?
UR_
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Re: Sheet Metal Workbench

Postby UR_ » Fri Dec 20, 2019 7:08 am

Fra88 wrote:
Fri Dec 20, 2019 5:54 am
What about k_factor?
Let's looo pass a comment :roll:
looo wrote: :bell:
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looo
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Re: Sheet Metal Workbench

Postby looo » Fri Dec 20, 2019 9:16 am

UR_ wrote:
Fri Dec 20, 2019 7:08 am
Let's looo pass a comment
Theoretically, it would be possible to add something like a k-factor with finite-elements too, but currently, the mesh-unwrapping doesn't include this. The algorithm minimizes only the energy introduced by linear membrane-deformation. As I understand, the k-faktor is a compensation-factor for plastic-deformation due to bending deformation. Theoretically, it should be possible to use shell-elements and "plastic relaxation" to remove introduced bending stresses.
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papyblaise
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Re: Sheet Metal Workbench

Postby papyblaise » Fri Dec 20, 2019 10:24 am

Whith mi experiance I can finish your unfold by hand
If you do it in sheetmetal , you have to finish by hand to use a "bigorne" (french world) and small hamer (planer) and weld it
If you need stemp it exemple cooker or car bodie , Fc can't unfold it , only a very powerful CAD can do it (use by airplane cie or bodie car cie)
Attachments
sphérical corner.PNG
sphérical corner.PNG (29.93 KiB) Viewed 335 times
spherical corner.FCStd
(130.95 KiB) Downloaded 9 times
chrisb
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Re: Sheet Metal Workbench

Postby chrisb » Fri Dec 20, 2019 11:47 am

papyblaise wrote:
Fri Dec 20, 2019 10:24 am
only a very powerful CAD can do it (use by airplane cie or bodie car cie)
To dampen expectations in case you want to switch to another system: It's not only a question of how powerful a CAD system is. It is a mathematical question and a part of a sphere or similar 3D surface cannot be unfolded without loss.
drmacro
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Re: Sheet Metal Workbench

Postby drmacro » Mon Dec 23, 2019 5:41 pm

chrisb wrote:
Fri Dec 20, 2019 11:47 am
papyblaise wrote:
Fri Dec 20, 2019 10:24 am
only a very powerful CAD can do it (use by airplane cie or bodie car cie)
To dampen expectations in case you want to switch to another system: It's not only a question of how powerful a CAD system is. It is a mathematical question and a part of a sphere or similar 3D surface cannot be unfolded without loss.
I would second this. It is a very math intensive issue.

Ask me about teaching a class of Boeing engineers how to use a sheet metal package of a CAD program many years ago. A student called me over and pointed at the error on the screen: "Klaus's hairy error!".

Klaus was the chief mathematician for our company... :lol: :o
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chrisb
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Re: Sheet Metal Workbench

Postby chrisb » Mon Dec 23, 2019 5:54 pm

:lol: