Today we had a hankering for some knots, and wanted to try building something big on the Mini. We chose fredhohman's trumpety Trefoil knot model from Thingiverse. Fred Hohman is a student at the University of Georgia who studies fibered knots with Dr. David Gay. This print is at the maximum possible scale that can be printed on the Mini; it's 120mm (nearly five inches) long:
Thingiverse link: http://www.thingiverse.com/make:87027
Settings: Printed on a MakerBot Replicator Mini with 4 shells and no infill, with raft and support. It didn't come out perfectly because that sort of setting does not include support on the inside/non-infill part of the model, so the print was full of gaps along the top-facing surfaces:
Next time I'll print this with standard solid settings instead of trying to be fancy. If I ever find the time to learn how to use Blender or Maya, I'll try to use them to surface-ify this model and make it a shell in a smarter way that can involve proper supports. If anyone reading this knows how to do that, please tell me about it in the comments or send me email.
Technical notes, math and Mathematica flavor: Fred Hohman will be guest-posting later this summer to tell us about the mathematics behind his fibered knot, and how he created it using Mathematica. According to his Thingiverse site he used RegionPlot3D, which looks like a promising method for other future mathy prints!