I was trying to see how the Self-Dividing Straightedge might work. This led me to try a search on the net which led me to US Patent 6243963 - Dividing rule.
http://www.patentstorm.us/patents/62...scription.html
Probably not at all related to the self-dividing straightedge but an interesting device if one had to divide a space into equal sectors.
Anyone else have any idea how a self-dividing straightedge works? Is it just a straightedge with equal graduations from the center?
Francis