Importing an STL file - won't import at all

[Anonymous]

Hi! New user and complete amateur here. But I've been through all the forum posts (and online help) and can't find the answer.

I have a design created by an engineering draftsman. He's sent it to me in .igs format. I need to 3D print the design, and my local library has said the file needs to be in .stl format. I used CAD Converter to convert the file - which appeared to work (although all the colours were lost). When I sent this file to the library, they said that it's just "a big J shape", which it is not, it's made up of 25 componants which I can see are all separate when I view the file in CAD converter. The library uses Up software (that comes with the 3D printer). So I call the Up people - and they say I need to send through 25 separate .stl files if there are 25 parts, and to use Meshmixer to make these 25 separate files. So I've downloaded Meshmixer. When I try to import the .stl file I get the message "Error opening file". 

I really don't know how to proceed further, and my school project is due in 2 days! As it's been a year long project, this is make or break for me. Does anyone have any suggestions as to how I should do it differently? Thank you so much for any help.

[Anonymous]

Seems to be some conversion issue. Maybe you need to join the different surfaces of a partial object after loading .igs before doing the conversion (Don't know CAD Converter)...

As MM is pretty stable importing STL : Can you open the STL file in some other app (except the converter) and save it from there? 

Did you try to convert to another format (e.g. OBJ) supported by MM ( supported formats )?

[Anonymous]

Thank you! I converted to OBJ and could import that file into Meshmixer. My next challenge, where can I see a list of all the components in my model, and convert each of these to an individual file? Thanks so much for your help.

[Anonymous]

Great OBJ did it. (First lesson learnt: Try to stick with OBJ as long as possible. Convert to STL only if it is needed for a handshake to some further software).

Now run ANALYSIS/Inspector at first to check if there are mesh errors indicated by pin markers in the tool. Blue: open boundaries, Red: non manifolds, Magenta: Tiny pieces (adjust the SmallThresh slider to keep tiny pieces you want to keep). You can repair the issues one by one by clicking on the marker spheres (e.g. if you want to keep some open boundaries) or click AutoRepairAll to do a global repair. If there are no pins: Simply Cancel.

(Inspector doesn't detect flipped normals (means the mesh might be partially show its inside at the outside). If there are such flipped regions you should see a pale pink stripe pattern on those areas. If there is such an issue you need to repair it by hand. Post a screenshot of such a possible issue and I'll try to guide you through.)

If all is fine:

Do EDIT/SeparateShells. If each component is a single mesh you should get each component a single object. You may activate an object by clicking on it in the scene or via the ObjectBrowser which should be visible after splitting.

If you need to export each component as a single file you need to activate it and EXPORT one by one to the needed format

[Anonymous]

Forgot:

If there are blue lines on the mesh before you run Inspector: Try to close them before using EDIT/CloseCracks. This still might leave some lines but it is worth a try.