STL files and 3D printing from TrueSpace 3.2

3D printing is something I have a love hate relationship with. I like the concept, but the implementation via fused filament fabrication (glue gun on a 3 axis plotter) leaves something to be desired. Early on in the 3D printing craze, I decided to build a RepRap Sells Mendel (http://reprap.org/wiki/Mendel).

I have been using TrueSpace 3.2 since approximately 2003, when Caligari used to offer free licenses. The software is simple and intuitive and oddly enough, still works on modern operating systems. I did not have any luck finding out any information on how to get a model from TrueSpace to an STL file, the file format commonly accepted by most slicing and CNC software. So as usual, experimentation provided the answer.

The following is the solution I came up with, if you have any better solutions, please contribute:

Software prerequisites:

  1. Model your part in 1:1 units – i.e. 1 unit in TrueSpace = 1cm in the final print.
  2. Save the scene as VRML (*.wrl). I had no or poor results trying to export the object in TrueSpace.

    How to export a model for 3D printing

    How to export a model for 3D printing

  3. Open the VRML file in MeshLab (File -> import mesh) and accept any post processing (OK).
  4. Export the mesh to an STL file (File -> export mesh as), accepting the defaults.

    Converting to an STL via MeshLab

    Converting to an STL via MeshLab

  5. Open up Netfabb basic and add the part (Project-> Add Part). Note the exclamation mark indicates that there are some problems with the mesh that need to be fixed. This seems pretty common when working with TrueSpace or Sketchup, but these errors are fixable.

    Imported model has errors

    Imported model has errors

  6. To repair the model, click the red cross type symbol on the top tool bar. Then apply an automatic repair (towards the bottom right of the screen) with the deafult repair option. Then click apply repair, and remove the old part.
  7. You should now have a part that exhibits no errors in the mesh. However, the scaling is still incorrect and the the part has somehow become rotated with respect to the X axis.

    Rotate and Scale in netfabb

    Rotate and Scale in netfabb

  8. The part can now be rotated 90 degrees along the X axis. The object can now be scaled along all axes by a factor of 10 to get the correct dimensions
  9. Export (part -> export part (as STL)).

    Finished part, ready for export

    Finished part, ready for export

  10. Print and enjoy the results! An optional step is to print out a test part prior to the final print (i.e. just a hollow cylinder or square shape). Measure the actual printed size from that of the design and then use those numbers to correct the scaling after the x10 scaling performed in step 8. Note that the scaling can be out of proportion (un-tick fix scaling ratio) to account for X Y and Z errors independently.
    The part fitted to the laser cutter lens assembly

    The part fitted to the laser cutter lens assembly

    The part printed out on the bed

    The part printed out on the bed

Success!

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