Part of my girlfriend's Christmas gift is this new set of earrings. The lower piece of this interlocking design had to be raised for the printing process, which also shows how they mate.
I started them by placing two symmetrical Arcs, slightly separated, and did a Rail Sweep of a Rectangle with filleted corners with ±180° Twist (complementary, so they'd be symmetrical, too).
The strut at the bottom of the upper piece was started by Extract Entity/ Extract face on the inside facet at the top of the lower piece, then filling it out and Extruding it to the sides.
(Rail) Sweep with Twist eats up a lot of space and processor time. I used ACIS / Expert Faceter Parameters, but my initial setting (0.01mm and 2°) resulted in a 180 MB STL file and hundreds of thousands of duplicate facets. MeshLab did a poor job of reduction; TurboCAD did better, but not good enough, so I changed the Faceter settings to 0.05mm and 5° which resulted in a 38 MB file (Shapeways has a limit of 50 or 60 MB, as I recall) that is smooth enough. Still a lot of duplicate faces, so it went through MeshLab, too. This fixed the irregular rectangular blotches you see in the image. IMSI should either improve their STL export function or add more than Fix holes to the options.
One unexpected thing was that I couldn't specify Polished Brass for this go-around at Shapeways and had to accept gold plating (that's going to wear, unfortunately). Another thing was that a lot of other people are doing the same thing this close to Christmas and I had to pay extra for expedited printing and overnight delivery to get them here before Christmas.
TC Pro Platinum 2019, 2018, 2017, 2016 & 2015 (all with LightWorks & RedSDK) & V21
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