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yesbird
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Swap inside and outside shells

I am printing clay form for internal fill and would like to preserve inside relief, but the inside outlines make it more fat and distorted (see image).
I know about "vase mode" but it will not helpfull, because it is too thin - I need at least 3 shells.
Can anyone suggest any trick to swap inside/outside ?

fill.png
Model has zero-thickness wall:
fil_modell.png
Thanks in advance.
JMP
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Re: Swap inside and outside shells

I think you are either going to have to redo your model so it has thickness that matches what you actually want to print or do something to trick the slicer into doing what you want. The only thing I can think of would be to make as many copies of the model that matches the number of perimeters that you want, and scale each one in x/y just enough to make it one perimeter bigger, and then print each stl concurrently with one perimeter. Not sure that would work though, I definitely would attempt to remodel first.
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yesbird
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Re: Swap inside and outside shells

Thanks for suggestions,
I thought about remodeling and can do it, but don't want to make it more complicated to preserve a simple workflow. Combining scaled STL's looks more attractive - I will try it.
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yesbird
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Re: Swap inside and outside shells

No, combining STL's is not working, looks like remodelling is the only solution.
gwhite
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Re: Swap inside and outside shells

If you have a model, a booleon combine operation should allow you to create what you need. It shouldn't be too tricky. If you just have a thin shell, you could use that to "split" something with the thickness you need.
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yesbird
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Re: Swap inside and outside shells

Unfortunately model thickness gives nothing,
I suppose topologi is the key. How S3D distinguish inside/outside of the model ?

Result even worse:
fil_modell.png
fill_large.png
parallyze
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Re: Swap inside and outside shells

yesbird wrote: Tue May 24, 2022 9:54 am Unfortunately model thickness gives nothing,
I suppose topologi is the key. How S3D distinguish inside/outside of the model ?
If the model does have outward pointing normals all around, like seen on some
of the screenshots, you might consider enabling
"Merge all outlines into a single solid model" on the "Advanced" tab.
This should slice as a solid with the "crackled" structure on the outside... the inside
will likely end up following the zero thickness wall, but this heavily depends on the
object and might not work at all, hard to tell without the STL.
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yesbird
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Re: Swap inside and outside shells

parallyze wrote: Tue May 24, 2022 1:06 pm If the model does have outward pointing normals all around, like seen on some
of the screenshots, you might consider enabling
"Merge all outlines into a single solid model" on the "Advanced" tab.
Thank you, parallyze, but this option is already turned on. I have resigned with low quality inside and ended up with adjusting relief details/scale on the model. For clay it more or less acceptable.
parallyze
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Re: Swap inside and outside shells

yesbird wrote: Tue May 24, 2022 2:09 pm Thank you, parallyze, but this option is already turned on. I have resigned with low quality inside and ended up with adjusting relief details/scale on the model. For clay it more or less acceptable.
Hmm.... if it doesn't slice as a solid with "Merge all outlines" enabled, then there's probably something wrong with your model file. Try
checking it using NetFabb or similar.
Edit: Just had a closer look again. From the pictures I thought there was already a 0 thickness wall acting as a "frame" inside
your object. But it does look like the fragments aren't connected at all?

I just tested the approach mentioned earlier in this thread:

1. create object using 3mm walls
2. dupcliate object, thin walls from outside/inside by 1mm
3. fracture thick object using %whatever%, I ran a quick test in blender
4. export fragments, clean up file
5. merge thin walled object from step 2 with cleaned up files from 4
_frac_1.JPG
_frac_2.JPG
With "Merge all outlines" enabled:
_frac_3.JPG
Still seems like a lot of work to do... otherwise all the parts starting mid-air will require supports.... ^^
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yesbird
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Re: Swap inside and outside shells

parallyze wrote: Tue May 24, 2022 4:25 pm Still seems like a lot of work to do... otherwise all the parts starting mid-air will require supports.... ^^
Yes, you are right, I am little bit lazy and would like to simplify workflow as much as possible. Besides that increasing the wall thikness assumes more material. In general I like this result - it's is not a mechanical part, clay can forgive an errors, but final conclusion can be done only after kiln ).

fill_zb.png
fill_result.jpg

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