Trying to remix and emboss existing STL - blue lines seem to be preventing this

[Anonymous]

I'm sure I'm missing something dumb.  STLs generated from here: https://touchterrain.geol.iastate.edu/

I've had 3 work as expected by remixing the needed side and inlaying the text by following this guide: https://www.youtube.com/watch?v=JXt6grv2AeY

However, I have one STL that has blue vertical lines.  No matter what I do I cannot seem to get it to remix and allow proper inlay of text.  I've even re-created it multiple times from said site. 

I'm essentially trying to make something like this for my father: https://www.thingiverse.com/thing:226414

I'm attached a screenshot of what I'm dealing with, any help would be appreciated!  I'll admit I'm a super-noob to 3d design.

Thanks,

Dan

[hfcandrew]

I believe those blue lines are open boundaries. Gaps/holes/cracks in the mesh. It is not 'water tight'.

Try:

A) Edit>Close Cracks

or B) Analyze>Inspector>Auto Repair All

or C) Edit>Separate Shells, Delete the noisy shells, Analyze>Inspector>Auto Repair All

or D) Edit > Make Solid

Or any combinations of the above.

[Anonymous]

Thanks for the ideas!  Just tried them all:

A) Appears to have done nothing.

B) Jacked the model all up.  See pic.

C) Crashed Meshmixer

D) Jacked up the model.  See pic.  

I went ahead and attached the STL.  Guess I can't attach an STL.    I'm not looking for someone to fix it though, I really want to understand what needs done so I can deal with it myself going forward.  Thanks!!!

[MagWeb · Accepted solution]

I tried several files from that source.

It's hard to repair these cracks in MM.

The most promising way is 😧 MakeSolid. Here it worked for all source files I tried.

Maybe you need to set a higher SolidAccuracy and MeshDensity.

----

Basically a STL file is a soup of loose triangles. They get welded to a mesh on import in a certain application. To do this two triangles to be welded on a common edge need to come with the very same vertex coordinates on the common vertices.

E.g.: If there's a triangle A>B>C and a triangle B>C>D both are welded on the edge B>C.

Now if there's a small error and there is A>B>C and (B+some error)>(C+some error)>D you can't weld both triangles any more (as "+some error" means you have a different point).

The easiest free way I know to fix this is to use Meshlab. 

-Load the source file

-Run Filters>CleaningAndRepairing>MergeCloseVertices and hit Apply in the filter dialog (defaults should work. The dialog stays open after applying-don't worry). 

-Export the result

MM should not show any cracks loading that result (hopefully).

-----

To upload a STL mesh here: Post a zipped file

[Anonymous]

Really appreciate the detailed explanation, that helps me understand.  Your suggestion of using Meshlab worked perfectly.  Thanks so much for your assistance!