In my quest to make a cool coaster, I wanted a way I could slice up a model so that each face could be printed, well, “face-up”, so I don’t run into problems with overhangs and supports and stuff gumming the works. I would then glue the model together later. (In the case of Coasters, I can also swap filaments and have the design “pop” on each side)…
In the process, I learned some OpenSCAD:
- F5 = “quick”, F6 = slow and build
- No such thing as “export this object”, it just builds and then you can choose to export everything.
- variables are lexically scoped, ie, more like constants. There are some dynamic variables as well.
- I had to remember some algebra.
- I applied some D.R.Y.
Here’s the result as applied to http://www.thingiverse.com/thing:60728 – first in “ShowMe()” mode:
And then SliceEverything() mode without the full fledged CSG operations:
And then SliceEverything() in the way that I could export an STL:
Yeah, that crashed. It was too complicated. I hate to take out the // Slice Everything, and instead, here’s just the front and an ear, exported to STL, and viewed in NetFabb.
Note: Its NOT fast, when doing the full build (F6). It also crashes less if run from command line – apparently the crash is during rendering to the screen?)
Show Me The Code
Since its getting a bit long, I’m linking to github below; but this is what it looks like, approximately:
update: I’ve tried to use this approach for several things now, and … its very fragile. So fragile, that I have successfully used it to create a print. Almost every model is “too complex” and fails at render. I might need to try a different language.. something that is rock solid.
