23 Apr
2010
23 Apr
'10
9:22 a.m.
Many examples in this general family are illustrated in this book: Woodturning Full Circle, by David Springett For example, spin a pentagram into a solid of revolution using a mirror line as the axis. Now slice along the original plane and rotate one half 2pi/5 or 4pi/5. Glue the halves back together at the pentagram faces. It's tricky to visualize how it rolls, but straightforward to make with a lathe. George http://momath.org http://georgehart.com On 4/21/2010 3:50 PM, Dan Asimov wrote:
I recently read of an odd solid shape, with I think an odd name, that has recently been defined...