STL to Solid - "Part object is not a shell" error

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chrisb
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Joined: Tue Mar 17, 2015 9:14 am

Re: STL to Solid - "Part object is not a shell" error

Postby chrisb » Fri Aug 17, 2018 9:55 pm

What's the use of this post besides citing a 4 years old post of Normand?
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bejant
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Re: STL to Solid - "Part object is not a shell" error

Postby bejant » Sat Aug 18, 2018 1:19 am

chrisb wrote:
Tue Mar 14, 2017 7:27 am
It was funny reading Mark's comment urging to upgrade.
(snip)
I do miss Mark's comments. He helped me a lot with my first FreeCAD steps.
I miss his comments too - sometimes he wrote some pretty humorous stuff. He joined the forum not long after I did, and he helped me a quite a bit along the way as well.
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NormandC
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Re: STL to Solid - "Part object is not a shell" error

Postby NormandC » Sat Aug 18, 2018 10:40 pm

chrisb wrote:
Fri Aug 17, 2018 9:55 pm
What's the use of this post besides citing a 4 years old post of Normand?
If you look closely at Maryfreecad's post, new text was added inside my quote. The following is *not* mine.

Maryfreecad wrote:
Mon Aug 13, 2018 2:33 pm
I have the same problem. Is there anybody to help please?
As the "IMPORTANT: Please read first before asking for help" announcement at the top states:
Please provide a complete description of your problem
The best way to get quick and efficient help is to not spare any details. What workbench and tools are you using? What steps did you take? What was the result? This will avoid back-and-forth exchanges and save time for everybody.
And please post the STL file you're having problems with, or a link to download it (without registration please).
scottdmills71
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Re: STL to Solid - "Part object is not a shell" error

Postby scottdmills71 » Mon May 27, 2019 1:39 am

versions 16,17,18 linux xubuntu 18.04
netfabb 2019 windows 10

thingiverse files
https://www.thingiverse.com/thing:291123
https://www.thingiverse.com/thing:1897860
https://www.thingiverse.com/thing:3555943
https://www.thingiverse.com/thing:2767754

Are there any new techniques to the process? I have tried 3 different versions of the software 16,17,18 and when I cant convert the part to a solid, no techniques i have tried are ever successful. I know I am not giving any specific file that I am having trouble with so here is just 1 that I would like to convert I have downloaded and tried techniques on all Battlestar galactica cylon raiders from thingiverse. Fantastically detailed models, however I want to convert the models to a functional toy within freecad, rather than printing and ripping apart physically. I have mnaged to get meshes out of almost all of them, but cannot convert to solid. I have ran them all through netfabb 2019 and repaired , took them back to freecad 16,17,18 and still cannot convert to solid. Is there anyway that I can just take the converted mesh find the holes and manually close them ? I can do it by using advanced utilities to create shapes however that is painstakingly slow when there are thousands and thousands of faces. Isn't there a better recipe to follow for converting something I download on thingiverse into something new from a STL file.
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quick61
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Re: STL to Solid - "Part object is not a shell" error

Postby quick61 » Mon May 27, 2019 4:36 pm

scottdmills71 wrote:
Mon May 27, 2019 1:39 am
versions 16,17,18 linux xubuntu 18.04
netfabb 2019 windows 10

thingiverse files
https://www.thingiverse.com/thing:291123
https://www.thingiverse.com/thing:1897860
https://www.thingiverse.com/thing:3555943
https://www.thingiverse.com/thing:2767754

Are there any new techniques to the process? I have tried 3 different versions of the software 16,17,18 and when I cant convert the part to a solid, no techniques i have tried are ever successful. I know I am not giving any specific file that I am having trouble with so here is just 1 that I would like to convert I have downloaded and tried techniques on all Battlestar galactica cylon raiders from thingiverse. Fantastically detailed models, however I want to convert the models to a functional toy within freecad, rather than printing and ripping apart physically. I have mnaged to get meshes out of almost all of them, but cannot convert to solid. I have ran them all through netfabb 2019 and repaired , took them back to freecad 16,17,18 and still cannot convert to solid. Is there anyway that I can just take the converted mesh find the holes and manually close them ? I can do it by using advanced utilities to create shapes however that is painstakingly slow when there are thousands and thousands of faces. Isn't there a better recipe to follow for converting something I download on thingiverse into something new from a STL file.
Not really. To this day, the STL format remains, for all practical purposes, a one way trip. Sure, one can convert between the two with simpler objects, like a cube, but anything with a curved surface, even when it converts to a solid, its still a bunch of flat triangles on the surface. The more triangles there are, the harder it is to work with.

I looked at one of the models you linked to and it is full of self intersecting faces, like a gaggle of them. This will never convert successfully to a solid. Even if you do get a "solid" out of it, it will be so full of selfintersect errors one would not be able to perform any further operation with it. One would be better off to do whatever needs to be done in a program like Blender. Much more useful for working with meshes.

Not really understanding what you mean by "a functional toy within freecad", but anything you might want to do with a meshed object in FreeCAD, converted or not, you can do better in a mesh modeler like Blender. The right tool for the job kind of thing. This coming from someone that has his workbench littered with at least a few custom angled screwdrivers as a result from various attempts to have them emulate a crowbar. :shock:

I can relate to what you are going through at the moment, as I was right there with you when I was first starting out with FreeCAD, and to be honest, it took a country minuet, (much longer than a New Your minuet by any measure), to come to the realization of what I have said above. Yea, it's learning another modeler program. The upside to learning a program like Blender is that it can be a wonderful companion in your modeling tool chest for providing a great way to render your models to photo realistic quality, as well as being the right tool for the job when working with and modifying meshed objects.

Mark
This post made with 0.0% Micro$oft products - GOT LINUX?