Symetry About TWO AXES 90S TO EACH OTHER - with Two Halves TWISTED

Seeing a Peter Rand Femisphere for the first time pushed my How In The Hell Did He . . . button.

When I was given a copy of David Springett's book Woodturning Full Circle for Christmas, my "How Do I Get Beyond Single Axis Symetry?" had a whole new area of turning to explore.

So . . . I'm putting together a series of web pages on just some of what David Springett calls Streptohedrons (twisted polygons), offsprings of Sphericons (bottom to bottom twisted double isoscoles cones). I'm building virtual 3D models with How They Were Created steps. You can download and play with them in Google's free SketchUp, or just view them from any angle, in 3D, with SketchUp Viewer.

Here are the SketchUp models I've been playing wiith - sphericons, femispheres, pentacon and hexacons