3D shell step file without thickness [Solved]

[zuheyr]

Dear colleagues,
I am a nearly newcomer to FreeCAD but I am learning and grateful.
Huge thank you to the developers.

I need to have a CAD step file of a zero thickness 3D shell, an elipsoid say with no thickness. Just like a 2D circle, a 3D
ellipsoid step file, can I do this? Thank you for reading and for your help!

Best, Zuheyr

[wmayer]

In the Part workbench there is a function to create an Ellipsoid. This, however, is a solid. To get a hollow shell out of it run this snippet:

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Part.show(App.ActiveDocument.Ellipsoid.Shape.Shells[0], "Shell")

Note: When using the clipping plane function of FreeCAD then both objects appear as hollow objects but commercial CAD packages may show the solid as massive object and the shell hopefully as hollow object.

[zuheyr]

Thank you so much, yes I do use the ellipsoid. I apologize for the trivial question but where do I run that snippet?

[domad]

Thank you so much, yes I do use the ellipsoid. I apologize for the trivial question but where do I run that snippet?

Hi zuheyr, greetings to the Community!
To get a shape without thickness:
Wb "Part":
- "Part" menu (or button) -> Create primitives -> ellipsoid;
Wb "Draft":
- select the ellipsoid -> "Drafting" menu (or button) -> Facebinder;

To get a mesh:
Wb "Mesh Design"
- select the ellipsoid or facebinder-ellipsoid -> Meshes menu (or button) -> "Create mesh from shape"

To cut Ellipsoid-facebinder:
Wb "Draft"
- Create a filled rectangle (or another flat shape);
Wb "Part"
- First select Ellipsoid-facebinder then rectangle-filled -> "Part" menu -> "Split" -> "Slice apart".

[wmayer]

Thank you so much, yes I do use the ellipsoid. I apologize for the trivial question but where do I run that snippet?

In the Python console. You can activate it with View > Dock windows > Python console

[zuheyr]

Million thanks to you Domad and WMeyer. I am grateful for your help.
Best wishes, Zuheyr

[domad]

Million thanks to you Domad and WMeyer. I am grateful for your help.
Best wishes, Zuheyr

We're glad you solved it, but now please add [Solved] to the topic title.

[TheMarkster]

In recent builds of 0.20 you can select the ellipsoid, press Ctrl+Shift+P and this will bring up the python console automatically, if it's not already visible, with obj assigned to the selected object. From there it could be entered:

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Part.show(obj.Shape.Shell1,"Shell")

[zuheyr]

Dear Domad,

I do as you instructed, but I cannot get rid of the dividing plane as well in the final cuts. Here is the picture:
I need a shape like a half broken egg without the plane as shown in the attached picture.

Many thanks, and apologies.
I am using FreeCad under Ubuntu 20.04 and it installs 0.18.

Best,
Zuheyr

[zuheyr]

Thank you very much! Taking more time and carefully following Domad's wonderful explanation
I did get a shell.

Instructive mistake: Apparently my mistake was to make the rectangle and facebinder solids before splitting.
This time I did not.

Thank you so much Domad, and to Wmayer for your valuable time and great help.
Much appreciated.

Best regards,
Zuheyr