Laminating Software (for lack of a better description)

[Lee DeRaud]

There seem to be dozens of apps out there that can take a 3D solid model of some sort (Sketchup, .stl, etc) and slice it into a bunch of cross-sections to be sliced out of thin material for rapid prototyping etc. What I'm looking for in the reverse: an app that will take a bunch of 2D slices with accompanying Z-location info and construct a 3D model of the resulting "stack". (Preferably without having to buy AutoCAD or some other multi-$K system.)

It's probably just a case of weak Google-fu on my part, but I'm not finding it...

[Steven Cox]

Hi Lee,
Just a thought and depending on what you wanted to design, CorelDraw does have some basic 3D capabilities using some of it's tools. Extrude is one where you can blend from one object to another and adjust the steps inbetween. You could also use Transform to precisely position the first and last object. Whilst Corel isn't really a full Cad program is does have some more than basic CAD capabilities.

[Doug Griffith]

This Google search may get you somewhere:
CAD reverse engineering "cross sections"

[Lee DeRaud]

This Google search may get you somewhere:
CAD reverse engineering "cross sections"

Thanks, that helped quite a bit: looks like the right search term boils down to "point cloud to stl". MeshLab looks like a candidate starting point...at least it's free. Worst case, I'll have to hack some C++ to convert the cross-sections to a sorted XYZ array and then generate two STL triangle entities from each adjacent four points. Sounds good, anyway, assuming I can figure some semi-intelligent way to handle the boundaries.

[Doug Griffith]

Another option may be to toolpath the layers as 2.5D. Then backplot and export the resulting plot as 3D CAD. You'll probably have to outset the XY by an imaginary cutter radius.

[Lee DeRaud]

Another option may be to toolpath the layers as 2.5D. Then backplot and export the resulting plot as 3D CAD. You'll probably have to outset the XY by an imaginary cutter radius.

My eyes just glazed over...I'm just starting to work out the workflow for CNC routing, and it's just driving me crazy how insanely complicated it is compared to just hitting 'print' in Corel for the laser. Initial reaction to the above was, "You can do that?!?" (I'm guessing the details will be radically different for any given 3D CAM app, assuming it supports the action at all.)

Re your suggestion: I assume that means generating (or at least modifying) the gcode for each contour spline/polyline/whatever by "hand", as they would be XY coordinates (at some constant Z) and would have to be rotated to XZ or YZ (with either Y or Z constant) to be of any use as a 3D toolpath. Or am I not thinking about this the right way?

[Doug Griffith]

I think I got ahead of myself. Backplot exports are still just 2.5D data. It would be redundant. There may be a nugget of info here:
http://www.imsrv.com/discus/messages/12/887.html

[Lee DeRaud]

Very cool...looks like that 'Accutrans' app that thread refers to may be the answer. What amazes me is that it's still available almost a decade later.
Many thanks!