Only back faces display?

Discussion in 'Software and Applications' started by philipwh, Aug 11, 2009.

  1. philipwh
    philipwh New Member
    Here's the model in question.

    I uploaded an .stl from Blender and it processed and scaled correctly, was accepted as printable, but both the thumbnail and 3D preview only seem to show the backfaces of the object from any given angle. Has anybody encountered this problem before, and does it mean there is a problem with the model itself that can be fixed? Thanks,

  2. WiKKiDWidgets
    WiKKiDWidgets New Member
    Hi Phil;

    What you are seeing there is an inside out object. hehe. Most likely the issue is that the Normals are all pointed to the inside instead of the outside. (I had the very same issue once.) Easy fix in Blender is to go into edit mode. and select all the verts, then hit {CTRL+N} to recalculate the normals to face outwards.

  3. philipwh
    philipwh New Member
    Okay, I just tried that, but now I just get an email saying it wasn't printable because "Your model has inverted normals in it." Which is sort of what I expected given that I wasn't getting a normals error before. Any thoughts?
  4. WiKKiDWidgets
    WiKKiDWidgets New Member

    Sounds like Blender is having problems deciphering inside from outside. Try removing doubled verticies.
    If that doesn;t work, PM the .Blend to me and I take a look.
  5. Youknowwho4eva
    Youknowwho4eva Shapeways Employee Community Team
    I have had models do this in the software I use. Usually I do a heal and it works. If you software doesn't offer a heal try copying the model into a new drawing and saving the new drawing, or exporting and re import back into the software. Both should cause an automatic solids heal. But seeing the image problem is on shapeways side I would think it would be their software having the issue, but you want it to be right so people can see it properly.
  6. philipwh
    philipwh New Member
    Well I tried a few different things and have got it working now, I think removing doubles might have been the thing that fixed it but I can't be sure since I did some other little adjustments all at once. Thanks guys.
  7. WiKKiDWidgets
    WiKKiDWidgets New Member
    Groovy man!

    Good job!