Challenges adding thickness to curved array shell

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JussyAD
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Joined: Tue Apr 20, 2021 4:30 pm

Challenges adding thickness to curved array shell

Post by JussyAD »

I have a curved array shell that needs thickness, but I'm encountering difficulties in achieving that. Initially, I attempted offsetting the shell, but that approach didn't yield the desired results. Next, I tried offsetting the base sketches and even downgraded the B-spline to an edge, yet still no joy. Additionally, I experimented with creating a solid and applying the thickness command, but unfortunately, that didn't provide a solution either. I'm wondering if there are any alternative approaches or techniques that I could try in order to achieve thickness for the shell.

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OS: Windows 8.1 Version 6.3 (Build 9600)
Word size of FreeCAD: 64-bit
Version: 0.20.2.29177 +426 (Git)
Build type: Release
Branch: (HEAD detached from 0.20.2)
Hash: 930dd9a76203a3260b1e6256c70c1c3cad8c5cb8
Python 3.8.10, Qt 5.15.2, Coin 4.0.1, Vtk 8.2.0, OCC 7.6.3
Locale: English/South Africa (en_ZA)
Installed mods: 
  * A2plus 0.4.60k
  * Behave-Dark-Colors 0.1.1
  * BIM 2021.12.0
  * CADExchanger
  * CurvedShapes 1.0.4
  * Curves 0.6.8
  * Dracula 0.0.2
  * lattice2 1.0.0
  * parts_library 1.84.0
  * Pyramids-and-Polyhedrons
  * ThreadProfile 1.84.0
Attachments
car body.PNG
car body.PNG (34.91 KiB) Viewed 1022 times
car body.FCStd
(19.1 KiB) Downloaded 16 times
drmacro
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Re: Challenges adding thickness to curved array shell

Post by drmacro »

I'd expect Thickness and 3D offset to fail...

This passes Geometry check:
Attachments
car body-mac.FCStd
(59.77 KiB) Downloaded 16 times
Screenshot_20230601_103643.png
Screenshot_20230601_103643.png (90.55 KiB) Viewed 1000 times
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
JussyAD
Posts: 377
Joined: Tue Apr 20, 2021 4:30 pm

Re: Challenges adding thickness to curved array shell

Post by JussyAD »

drmacro wrote: Thu Jun 01, 2023 2:35 pm I'd expect Thickness and 3D offset to fail...

This passes Geometry check:
Thank you. Is the thickness uniform throughout like a true offset?
drmacro
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Re: Challenges adding thickness to curved array shell

Post by drmacro »

JussyAD wrote: Thu Jun 01, 2023 3:10 pm
drmacro wrote: Thu Jun 01, 2023 2:35 pm I'd expect Thickness and 3D offset to fail...

This passes Geometry check:
Thank you. Is the thickness uniform throughout like a true offset?
Probably not, I did not check the location of the scaled clone.
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thomas-neemann
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Re: Challenges adding thickness to curved array shell

Post by thomas-neemann »

JussyAD wrote: Thu Jun 01, 2023 1:59 pm
If that's a solution for you, I can shoot a video for you
Bildschirmfoto_2023-06-01_20-08-19.png
Bildschirmfoto_2023-06-01_20-08-19.png (78.21 KiB) Viewed 879 times
car body-2007.FCStd
(45.21 KiB) Downloaded 15 times
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Vincent B
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Re: Challenges adding thickness to curved array shell

Post by Vincent B »

thickness doesn't like theses kind of splines. :roll:
sketches slightly changed.
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car body_vb.FCStd
(952.03 KiB) Downloaded 12 times
JussyAD
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Re: Challenges adding thickness to curved array shell

Post by JussyAD »

thomas-neemann wrote: Thu Jun 01, 2023 6:09 pm
If that's a solution for you, I can shoot a video for you
Thanks, Thomas. I'd appreciate that!
JussyAD
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Re: Challenges adding thickness to curved array shell

Post by JussyAD »

Vincent B wrote: Thu Jun 01, 2023 8:10 pm thickness doesn't like theses kind of splines. :roll:
sketches slightly changed.
If only it did, but I guess we have to accept workarounds until it does. This idea of offsetting part by part and then stitching it all together is brilliant and yields a valid shape too. Thanks for the advice.
freedman
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Re: Challenges adding thickness to curved array shell

Post by freedman »

I haven't tried lately but Thickness in PartDesign can work if the outside edges are made correctly, as an example this motor oil container, Thickness worked to hollow out the jug. Thickness gets complicated around the handle so I remember being surprised.
I also remember it being a bit fragile as one would expect. I know if the radius is too small Thickness will fail so Tangent surfaces become important.

You can also pipe a sketch drawn form, this would require you to draw the sheet metal thickness.
freedman
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Re: Challenges adding thickness to curved array shell

Post by freedman »

Here is a Pipe of a sketch drawn thickness. It passes BOP.
Attachments
pipe66.FCStd
(156.81 KiB) Downloaded 15 times
Shape66.png
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