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.STL: non-closed manifold surface

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Old   October 28, 2013, 06:05
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phil
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Hey,
i've got similar problems to giulio. My biggest problem is, that my stl file is not closed and i get pretty bad snapping at the edges.
I tried to repair/clean my stl with Meshlab but without big efforts.

Perhaps you could have a look at my stl. The geometry will be used as a pipe streaming through the big patches.

kanal_original.txt


Greetings
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Old   November 2, 2013, 14:39
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Greetings Phil,

I had a look into your file and here's what I got:
  1. surfaceCheck indicates that there are 8 unconnected regions:
    Code:
    surfaceCheck kanal_original.stl
  2. The reason for this is shown in the attached image, namely that not all vertices are connected to other vertices.
Therefore, it's as good as there are surfaces floating surfaces, when it should be a solid.

As for fixing it... in Meshlab, you can use from the menu "Filters -> Remeshing, Simplification and reconstruction -> Delaunay Triangulation". I wont be a perfect triangulation, but at least it fixes the problem

Best regards,
Bruno
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File Type: jpg kanal_original.jpg (35.0 KB, 90 views)
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Old   February 27, 2015, 03:37
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Hi,
may I also ask sth regarding surfaceSubset?
I have copied the surfaceSubsetDict and try to run it for my case but I get the error

Istream not OK for reading dictionary

Any ideas how I can fix this?

Thank you very much in advance for your help!!!
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Old   February 27, 2015, 16:19
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Quote:
Originally Posted by pizzaspinate View Post
Hi,
may I also ask sth regarding surfaceSubset?
I have copied the surfaceSubsetDict and try to run it for my case but I get the error

Istream not OK for reading dictionary

Any ideas how I can fix this?

Thank you very much in advance for your help!!!
Greetings pizzaspinate,

I think I saw a similar thread of yours on this topic, where you then stated that you managed to fix it. But now I see that you asked this here as well.
Therefore, if you've managed to solve this problem, then please indicate how you fixed it.

If you haven't solved this problem, then please provide more details (namely, if you did any modifications to the dictionary file "surfaceSubsetDict"), since that error message can occur in a lot of situations.

Best regards,
Bruno
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Old   March 3, 2015, 05:41
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Hi Bruno,

yeah I posted it twice because in my experience you don't get much responses when you reply in old threads. Sorry for that.
Yes I managed to fix it. I had to enter the command:
Code:
surfaceSubset surfaceSubsetDict UCAV.stl UCAV_prob.stl
in constant/trisurface to avoid the error.
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Old   April 15, 2016, 06:41
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dear wyldKat,

very quickly : i need to fix some .stl files to then use in OF. I have blender.
How to just add a lower cap (as inlet) to this stl https://www.dropbox.com/s/hzgq9l0e72...perta.stl?dl=0 (which is the bottom of my object), so to have one single .stl file which passes the surfaceCheck ? Could you gently post it ?

This old link you suggested here http://engits.eu/wiki/index.php/Tuto...ing_Geometries where is now?

thanks a lot, have a nice day,
i
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Old   April 15, 2016, 18:00
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Quote:
Originally Posted by gned View Post
very quickly : i need to fix some .stl files to then use in OF. I have blender.
How to just add a lower cap (as inlet) to this stl [...]

This old link you suggested here http://engits.eu/wiki/index.php/Tuto...ing_Geometries where is now?
Quick answer: I've updated the link on the post you mentioned and the new link is this one: https://github.com/enGits/engrid/wik...and-enGrid-1.2

And sorry, but I don't have the time needed to fix that STL file, specially because I barely know how to use Blender
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Old   April 24, 2016, 07:01
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Quoting the PM you sent me:
Quote:
Originally Posted by gned
Hi wyldkat,
thank you for the updated link, it has been very useful.
Using different tools, as Blender and Freecad, and operations of cutting/extrusion/filling I got this final stl

https://www.dropbox.com/s/z5tyrv4y2n...y_018.stl?dl=0


It's clean but when you surfaceCheck it, still it splits the external case and the inside poppet in two .obj files (I think just for a different not conform triangulation of the two objects at their border more than for reasons of really non- stitching edges/gaps there).

So which tool or OF surface* utility you usually recommend to obtain a really perfect stl file, still divided in different solids as this one, but which is one unique watertight stl file, before sHM it ?

thanks a lot,

i
Sorry, like I wrote in my previous post, I don't have time to look into this.

OpenFOAM itself doesn't have utilities that will solve these problems automatically.

You can try and use this STL and see if snappyHexMesh can still use it, regardless of the errors.
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Old   April 28, 2016, 08:53
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hi, I've problems using surfaceCheck. And I already used Meshlab and Admesh but it isnot completely removed that problems.
What should I do?
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Old   May 1, 2016, 19:04
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Quick answer: Creating waterproof STL using snappyHexMesh or salome
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