http://geargenerator.com/#200,200,100,6,1,4,269.0999999999988,5,1,8,2,4,27,-... Matthias Wandel's Gear Generator is a tool for creating involute spur gears <http://en.wikipedia.org/wiki/Involute_gear> and downloading them in SVG format. In addition it lets you compose full gear layouts with connected gears to design multiple gears system with control of the input/output ratio and rotation speed. Gears can be animated with various speed to demonstrate the working mechanism. video of Windows version of Gear generator https://www.youtube.com/watch?v=9MycFQKnZkA -------------------------- Stuart Anderson