Hi Tony - when you trace the background image you mean that you are drawing curves over top of it, right?

In order to export to an STL file you must then do another step of creating some solids from those curves.

STL files are meant to hold a solid model in triangulated form. If you have only drawn some outline curves you do not yet have a solid model, you only have wire curves.

You can create a solid model from your curves using a variety of construction commands - one of the most simple is Extrude. There are some tutorials here: http://moi3d.com/2.0/docs/tutorials.htm which go step by step through creating some simple solids, and if you watch those tutorial videos you can see that one of the steps does involve drawing curves, but then you use those curves in commands like Extrude, Revolve, or Sweep to construct shaded solid objects - it's those solid objects that can then be exported to STL files and transferred to Cut3D.

If you have only drawn outline curves alone, then you have not yet finished the process of constructing a solid object.

Does that make sense? Please let me know if this is still not clear. Maybe if you could post the 3DM model file of your current results that would help me to be able to see what you are working with that is having a problem right now.

- Michael