CADSpan and vanishing model bits...

Discussion in 'Software and Applications' started by dynath, Aug 30, 2011.

  1. dynath
    dynath New Member
    Ok I've been having this problem for about a month now. At first I thought it was my software installation since i had reformated my machine and reinstalled. However I've tracked it to CADspan's STL surfacing in Sketchup.

    I'm pretty new to 3d modeling so I'm learning in google sketchup. In order to upload here I started using the demo version of CADspan. For the past month whenever I resurface a model to get a Watertight STL with CADspan parts of the model litterally disappear. I don't mean small holes appear but entire arms off of the figures i'm trying to build vanish.

    A freind who's a bit more experienced than me exported a model to 3ds max 2010 and then to STL. the STL file he made wasn't water tight but it did have all the parts. afterwards we tried processing it through CADspan's software again and it had missing parts again.

    It seems random what vanishes. I processed the same file multiple times and got different parts vanishing each time.

    I asked the CADspan support people and they didn't have an answer, they just told me the model error was caused by sketchup but gave no suggestion how to fix it or indeed what "error" was causing this.

    Has anyone else had this problem? and if so whats causing this and how can I correct it?
  2. denali3ddesign
    denali3ddesign New Member

    Sorry for asking a question instead of answering yours, but what does CADspan do? I'm asking honestly since I use Sketchup but have never used CADspan.

    For simply converting to STL, I use this plugin.

    Last edited: Aug 31, 2011
  3. dynath
    dynath New Member
    CADspan "shrink wraps" the model. basically it gapfils and makes a unified shell removing internal geometry. the result being a single piece STL file that is watertight. I was having extensive problems exporting to STL before I startedd using it, I tried the plugin you link as well as another one called STL4SU but I couldn't upload the models nor open them in other software, for some reason they just came out unreadable. CADspan was easier for a while, most of the models i've submitted have been processed through it. But not I'll process a model and its sort of a crap shoot what will vanish. Its really frustrtating so I hoped someone here would have been using CADspan and might give me some tips.
  4. denali3ddesign
    denali3ddesign New Member
    I use a different tool to help me make my model manifold - this excellent plugin called Solid Inspector, plus the built-in Outer Shell tool to remove internal geometry. It sounds like CADspan is supposed to be more automated - when it works - but I have never found a model that can't be fixed using Solid Inspector.

    If you want me to take a look, you may PM me the model and I'll see what the problem is.

    Hope that helps,

    Last edited: Aug 31, 2011
  5. cwho
    cwho New Member

    CADspan here. Indeed CADspan is a different approach to creating 3d printable geometry or at least the online resurfacer is. There are actually several tools. If you want, there is a simple stl dump (the rightmost icon in the tool bar) that exports your onscreen or selected geometry in the STL format. This is the same as other file exporters and is pretty simple.

    We also have a view mode that helps you find open edges and flipped normals. It is simply a view style and is useful in conjunction with other tools to find holes etc.

    The online resurface is the unique tool. What it does is to take your geometry and sends it off to an instance we start for you on the Amazon Cloud. Then it creates a 3d scan or voxelization of you model and then attempts to create a new mesh that surrounds what it sees as the "outside" of your model.

    We developed it for 3d printing Architectural models where part of the problem is getting rid of a lot of internal components. It works well for that. What we are trying to figure out is why it is less reliable for some small objects. If they are simple, it does weird things. We are working on this..

    Thanks for trying it. Remember you can always use the other tools independently of the resurfacer.

    Best wishes
  6. dynath
    dynath New Member
    Ok Cwho since you represent cadspan maybe you can answer whats going on. When I use Cadspan to resurface a mesh parts start disappearing. Generally its high poly organic parts.

    I methodically go through the model with solid inspector and remove holes to make it solid, if I output it with STL4SU the model shows as water tight in NetFabb and will work without loss in shapeways. However, if I upload the same model to Cadspan and resurface it then download the processed file and look at it in NetFabb it shows litterally thousands of manifold faces and if uploaded to shapeways the model will be missing massive sections of the file.

    Personally I hate being "methodical" obsessing over tiny holes wastes time when I want to just MAKE something. Cadspan is an awesome solution most of the time but it just seems to slow me down lately.
    Last edited: Sep 17, 2011