Volume cost question

Discussion in 'General Discussion' started by 118124_deleted, Jun 28, 2012.

  1. Youknowwho4eva
    Youknowwho4eva Well-Known Member
    Your hollow model, does it have a path from the inside to the outside? If not the software will delete internal geometry, so basically the price is for two non-hollow spheres.
     
  2. stop4stuff
    stop4stuff Well-Known Member
    ^^ what Mike said ^^

    A useful free tool for checking your models for volume, surface area and all other kinds of measurements is NetFabb Studio Basic (its also good for a whole host of other things too)

     
  3. stonysmith
    stonysmith Well-Known Member Moderator
    You need to mark the two models as available to the public.. we can't see them to try to help.
     
  4. I put a pinhole 1/1000th of an inch in diameter in a test model. It reduced the price of the model 80 percent compared to a similar model without the pinhole. Thanks again for the suggestions.
     
  5. ZoeBrain
    ZoeBrain Member
    Of course to make it printable, the hole has to be large enough to recover the powder. A 1cm radius hole should do it, though two would be better.
     
  6. stonysmith
    stonysmith Well-Known Member Moderator
    1cm radius may be a bit larger than necessary. I have been successful with two 2mm holes, but it really depends upon the geometry of the shape you're constructing. Shapeways is currently granting some exceptions for "Trapped Material", but they are reserving the option to change that rule in the future. A lot of that has to do with how much material is being trapped. For your sphere, you've got a LOT of trapped material inside there. Even for your model "helix04".. there might still be some trapped material, but it wouldn't be a significant percentage of the volume of the model.

    Remember, the point here is that they want to be able to blow pressurized air in one hole and have (most) of the material come out the other.

    The thing is.. they don't know what you or your customer expect to have the trapped material or not. If you don't care.. then great. But if you truly want "hollow", then they can't read your mind. Putting some holes in the model will allow the unused material to drain out. Obviously, as you increase the complexity of the model, you'll have to get more creative where you put the holes.
     
  7. Why would there be trapped material in a hollow space? If it's 3D, the printing stops when the software sees air.
     
  8. Youknowwho4eva
    Youknowwho4eva Well-Known Member
    Few things, All of Shapeways materials use a support material to support unsupported pieces of your model.

    Second, for the drain hole. I can say for FUD and FD, that a small hole is fine, it will result in the build material (wax in this case) to be trapped. I don't know if the other materials require sufficient drainage as most the other materials, the support material is unfused build material, and some can be recycled.
     
    Last edited: Jul 2, 2012
  9. stop4stuff
    stop4stuff Well-Known Member