Question regarding thicken a stl model

[jihuili]

Dear all:

I have a stl model of a femur and need to add a layer of cartilage on the femoral head. Since the stl model is composed of a lot of small triangles, thicken those triangles (altogether) will have normal problem. If I thicken the triangles one by one (hundreds of them), it will end up with hundreds of parts with gaps or overlaps. I would like to have one solid part after this thicken process. Anyone has a better idea? Or any other software can do this?

Thanks a lot,

James

 

[tph216]

You're right that stl is made up of small polygons. It's a nightmare to work with, for typical CAD users.

The thing you want to do, is add more triangles, really, where necessary. I suspect there might be two options worth pursuing.

i) Find out where the original file came from, and get a copy in a different format that is easier to edit. It might be likely that it came from point cloud data that either has or hasn't been surfaced. If it has been surfaced, you could probably use that and use a more 'arty' 3D package like Rhino or 3DSmax to manipulate the surfaces as you desire.

ii) Undertake some surfacing operation yourself on the model you have. There must be something that can identify or fit surfaces over the stl polygon model. Once you've achieved this, it's then a case of adapting the surface model as I mentioned previously, Rhino or 3DSmax.

I've never heard of anything where you can change STL files directly, though I may be surprised.

 

[ennjg]

We work with STL files all the time, but NX is rarely the best package for processing them. Something like Geomagic Studio or Materialise Magics have tools designed specifically for editing (repairing, smoothing, thickening, etc.) STL files and can handle very large file sizes; we often have datasets comprising >10million triangle.

That said, this software isn't cheap. There may be some cheaper/free alternatives but I could be wrong.

As the previous post describes you may be best to surface the data and then manipulate that to your requirements.

 

[jihuili]

Thank you both for the replies. I may have to find another software to do this.

Best,

James

 

[PSI-CAD]

Hi,

I have found a sample method to create a 3D model from an stl body.
Send me your model if you are interested of more information

Regards

Didier

http://www.psi-cad.com

 

[hudson888]

I've probably done this before if you take a look at my website or contact me I may be able to help.

Best Regards

Hudson

www.jamb.com.au

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