manifold, normals, strange texture

Discussion in 'Design and Modeling' started by fourdee, Aug 31, 2009.

  1. fourdee
    fourdee New Member

    I'm having a bunch of trouble with my models... I'm using Cheetah3D.

    Here is my process:

    - Create type in Illustrator
    - Convert to shape
    - Put holes at top
    - Make compound path to punch holes
    - Save as SVG
    - Import SVG into Cheetah
    - Put SVG path into extrude object
    - Save as STL

    When I import "fourdee.stl" into Shapeways, it works, but the image and 3d view shows strange lines across the front, but in Cheetah, it's perfectly flat.
    See model 49069

    When I import "fourdee-linear.stl" into Shapeways, it tells me only manifold objects can be printed. This is the same as the previous object, except I changed the bevel to linear.
    See model 49070

    When I import "helvetica2.stl" into Shapeways, it tells me the object has inverted normals.

    I've been messing with all of this for a few days now, so I've lost track of everything I've done trying to get things to work...

    Attached Files:

  2. fourdee
    fourdee New Member
    Shapeways guys? Anyone?
  3. Youknowwho4eva
    Youknowwho4eva Shapeways Employee Community Team
    as far as the lines on the surface, all of them show that. The best way is to open your stl in meshlabs. thats how it will look
  4. afrodri
    afrodri New Member
    There might be something wrong with the STL file, As MiniMagics won't open it, though MeshLab did. Perhaps try a different format?
  5. bartv
    bartv New Member

    the striping you see after uploading 'fourdee.stl' is due to the rendering algorithm that we use - it'll try to smooth the surface of your object. The printed result will follow the exact geometry though, so it will print out just fine.

    I also inspected the beveled object and I'm sorry to say that Cheetah made quite a mess out of that one. I tried to fix it for you but couldn't clean out all the self-intersections and open faces it had left behind :(


  6. fourdee
    fourdee New Member
    Can you suggest an easy 3D app I could use that is like Cheetah but does things correctly? I've tried Blender but it makes no sense to me :)
  7. iguffick
    iguffick New Member
    I know where you are coming from with Blender.
    I first looked at Blender years ago, found I could do nothing with it, because I couldn't understand the interface, and give up.
    I had another try about a year ago, ran through a few tutorials, bought a few books. Now I love Blender and find I can be quite productive. I've probably got a lot to learn still, but I know I can get things done and if I have problems with something - there will be a tutorial or forum I can turn to.

    So it is worth sticking with to give it a go.

    For a total beginner I would recommend "Blender for dummies" by Jason van Gumster. You can also learn the basics from the many text or video tutorials around.
  8. WiKKiDWidgets
    WiKKiDWidgets New Member
    You have touched on a common chord with regards to Blender. But i have to jump to its defense simply because it is so much more than a modeling tool. Yes, the interface is cumbersome, and the learning curve is pretty steep. But there is so much documentaion and tutorials out there to help you. In addition to multiple forums (Including this one) where you can ask for assistance for various problems. Folks like me and Bart (Shapeways employee) have a great deal of experience with Blender and are more than willing to assist.

    Don't give up!

    Here are some great sites to check out learning the basics of Blender:
  9. bartv
    bartv New Member
  10. afrodri
    afrodri New Member
    My biggest complaint with the Blender interface, is that once it becomes second nature, it bleeds over into other applications. Now I keep hitting 'A' to select and unselect things in Word or PowerPoint (well, Pages and Keynote...). :)
  11. WiKKiDWidgets
    WiKKiDWidgets New Member

    DOH! How could I forget that one. Sorry B@rt!

  12. WiKKiDWidgets
    WiKKiDWidgets New Member
    I hear ya!

    the best advice I can give when it comes to Blender...

    Always: One hand on the mouse, one hand on the keyboard. Once you get down the keyboard commands (All 8.7 bazillion of them) Blender is a breeze!


  13. Youknowwho4eva
    Youknowwho4eva Shapeways Employee Community Team
    I really need to start learning blender, I just don't have the time or patience right now. But what I've seen from it is amazing. I'm wondering though, is it capable of producing precise models? As you can tell from my models I use a very precise modeling program. But if Blender can do precise, maybe I can use learning it as a work thing :p get paid to learn it.
  14. WiKKiDWidgets
    WiKKiDWidgets New Member
    Sure can mate. I make lotsa hop up parts for RC cars and stuff. Common for me to make bearing slots and all sorts of miniature doo-dads. Blender does not have a real world unit of measurement (like most 3D programs.) so I work under the assumption that one blender unit is equal to 1mm and use STL format. The basics are not that difficult to learn. the interface is confusing to the uninitiated because it does so much more than just modeling.

    You can make a full blown movie with Blender, Games, Physic demonstrations, Jurrassic park 5!! hehe

    There are several consortiums out there tight now trying to implement CAD functionality into Blender as well.

    Get in there! When you get stuck ask! There are 2 million or so users all over the world.

    Here, download the Blender art magazine. That should get you drooling.
  15. Youknowwho4eva
    Youknowwho4eva Shapeways Employee Community Team
    I'll have to check it out, I may have to export the models to my other software to verify dimensions. I'm American so mm are stupid with their logic of being related to real world things and not the dimensions of some kings foot. As long as it's better able to handle more complicated models. My Mayan pendent took me a few days because my software was struggling.
  16. afrodri
    afrodri New Member
    Because Blender is unitless, you can pretend one Blender Unit = 1 inch as well. The Shapeways STL upload allows you to specify 1 unit = 1 mm, 1 meter, or 1 inch.

    Blender seems quite speedy, and does a good job of conserving memory.
  17. Youknowwho4eva
    Youknowwho4eva Shapeways Employee Community Team
    I'm starting the tutorial videos now. Man learning sucks even when you're getting paid to do it.
  18. fourdee
    fourdee New Member
    Can either of you tell me how I can import something from illustrator (arranged type) and extrude it? I suck at learning by reading random stuff... I just need to be nudged in the right direction...

    Things seem sooo overly difficult in Blender...
  19. iguffick
    iguffick New Member
    Check out :-

    There are a few tutorials on precision mechanical modelling.
    Once you figure out how to use the 3d cursor, it is very useful.
    You can snap the 3d cursor to one vertice/object and then scale/rotate/etc another set of vertices/faces/objects.
    When doing mechanical models my most used key combination is Shift-S to snap the 3d cursor.
    Also learn how to use the 'Spin' button.

  20. WiKKiDWidgets
    WiKKiDWidgets New Member
    Nah, once you know its a breeze.

    To import from illustrator, you use Import --> Path

    this import supports several different file formats, so export from Illustrator accordingly.

    Once you have it in Blender, if it is just an outline, then you will need to fill in the void. You can use {Shift+F} to add faces (A surface) to the outline.

    Then, to extrude Blender uses {E} on your keyboard to accomplish extrusions.

    Give that a go and let me know.