Symmetrical Tensile Tetra
A very accessible, inexpensive and elegant tetra. The hubs are sized for inexpensive 3/16" and 1/8" dowels, but can easily be resized for larger diameter dowels. The five hubs print on my MakerBot Rep 2 in less than an hour and a half. I use hot glue to firmly set the dowels within the hubs. More construction details are in my original tensile tetra post. http://www.thingiverse.com/thing:923670
Dowel lengths are as follows. Since the tetra is symmetrical the locations for the different dowels should be fairly obvious.
4 @ 431 mm
2 @ 363 mm
2 @ 158 mm
1 @ 181 mm