Printing Grandpa is giving issues

Discussion in 'Technologies and Hardware' started by tristan_bethe, Oct 29, 2012.

  1. tristan_bethe
    tristan_bethe New Member
    Is it just me or did something change in the way .wrl files for color prints are checked?

    I did quite some color prints in the past and thought I had my workflow down.

    However I had quite some difficulty when I tried to upload a color model the last few attempts. The error emails do not specify what the problem is however only that I need to give my model a bit of extra love.

    I took the existing grandpa model and made a 'sinterklaas' version of it (hope the family will be amused next december :)

    I kept the triangles well under 500.000 did all kinds of error checks... Also I opened the wrl in notepad to make sure the texture name and path check out.

    Below are 2 exports of exactly the same source. One is a .STL without color. The other is a .WRL with texture.

    imageafter.com/temp/tristan/SinterOpa3STL.zip
    imageafter.com/temp/tristan/SinterOpa3WRLcolor.zip

    The STL uploads perfectly however the .WRL 'needs more love'

    Anyone an idea what is wrong?

    Does the server check wall thickness when uploading an .WRL? If so that could be the problem since the wall thickness of colored sandstone is 3mm and the white strong and flexible is 0.7 but I guess if that is checked it would be easy to mention in the error email right?


     
  2. virtox
    virtox Active Member Moderator
    Strange..

    I'll take a look.

    Any luck with uploading one of your old models?
     
  3. tristan_bethe
    tristan_bethe New Member
    oeh! good idea! See if the old models give the same probs!
     
  4. virtox
    virtox Active Member Moderator
    Initial inspection of your model did not show anything strange, except for a very funky dressed grandpa :) awesome model variation!

    Also the guidelines for sandstone have been updated and 2mm walls are also possible now:
    http://www.shapeways.com/materials/sandstone-design-guidelin es
    And the polygon limit has been upped to 1 million :)

     
  5. tristan_bethe
    tristan_bethe New Member
    woot! thats amazing to hear.. so thats probably not the issue...

    btw here is a link to the succesfully uploaded stl file: http://shpws.me/lPPX

    I had another 3D print issue a few months back that was solved by reducing the triangles to 300.000 instead of 450.000 which was my original size. apparently a memory issue.

    I've downloaded en re-uploaded this model of the less funky grandpa: http://shpws.me/lnKA

    I've yet to receive confirmation but that seems to be a good sign. The error of sinteropa where very quick after uploading...
     
  6. tristan_bethe
    tristan_bethe New Member
    mmh I've just read that the minimum bounding box is x+y+z≥75mm My print is +- 35 high... is that the issue? or am I reading it wrong? in any case the normal grandpa was 4cm high
     
  7. virtox
    virtox Active Member Moderator
    Hmm, that is quite small!
    Sounds like that might be it, but the email should just say that if that is the case ;)
    Should be easy enough to test though, scale it up and see ;)

    Oh and in my experience, old models that do not adhere to the rules may or may not be rejected on ordering ;)
    Likely depends on the actual repeat printability.
     
  8. tristan_bethe
    tristan_bethe New Member
    ah the old model uploaded perfectly... how weird!
     
  9. virtox
    virtox Active Member Moderator
    Hmm, curious...

    See if you can find any differences between the files.
    I have limited pc access atm.
    But perhaps, spaces/newlines/dos/unix filetype or format issues?


     
  10. virtox
    virtox Active Member Moderator
    Perhaps try this, I just opened and saved it with Meshlab, wrl file is several MB smaller, not sure why.


     

    Attached Files:

    • Opa.zip

      File size:
      8.3 MB
      Views:
      154
  11. tristan_bethe
    tristan_bethe New Member
    Ah too bad the meshlab version gives the same problem:

     
  12. Fredd
    Fredd New Member
    Tristan I opened up the model. It showed some non manifold errors. Basically several loose verts along the surface. I guess in the stl upload SW thought you wanted them booleaned, but were so small, it deleted them, but printed. The loose verts made it non manifold in the wrl. Its a easy fix anyway.
    Keith

    The floating loose verts were the culprits. Dimensions and volume remain the same with the wrl fixed.
     
    Last edited: Oct 29, 2012
  13. tristan_bethe
    tristan_bethe New Member
    Fredd,

    Thanks so much for checking it out. Just read your reply since for some reason I am not getting alerts on new posts anymore :cry:

    May I ask what software you used to check and how you fixed it eventually?

    Also do I understand correctly that the SW upload does automatic booleans with intersecting meshes? That would help me understand/visualize the SW upload a bit better!

    *just discovered you have to check 'Post Notification' at each post -do'h
     
    Last edited: Nov 8, 2012
  14. Fredd
    Fredd New Member
    I know that SW will boolean union stls where you have several manifold objects with intersecting volumes(as long as they are not too small). No idea about vmrl2 for colored models. Beware a boolean operation, you might have to unwrap the mesh again.

    I opened the file in Blender, nice little free program. For the uses would would need of it, would be simple to learn about 5 techniques.
    By the way, I loved Pope Pawpaw.
    Keith
     
  15. bartv
    bartv New Member
    The Mesh Medic boolean operation often has a hard time with vrml2 models with UV texturemaps - once it corrects a mesh problem it does not know how to re-map the textures. In these cases, it's better to fix the model by hand..

    Bart
     
  16. Fredd
    Fredd New Member
    Barty that is so true. About anytime you boolean objects with uv maps, you normally wind up remapping the joined object. Another example of why you should properly create a model for 3D printing from the start, learn how to check for errors and fix them, instead o being lazy and depending on mesh medic/ netfabb basic to fix them all the time.

    Keith
     
  17. bartv
    bartv New Member
    There's nothing wrong with being lazy of course ;) But yeah, in general it's better to know what you're doing and create valid geometry from the start.

    Cheers,

    Bart