Tex, I'm pleased that you enjoyed my article!
You can find a definition and description of cycloids at the following website. online.redwoods.cc.ca.us/instruct/darnold/CalcProj/Fall98/NateB/definition. htm There you'll see that a cycloid is the locus of a point attached to a circle rolling on a line. If you get the radius, etc. correct, then you can cut out a circle, roll it along a straight edge, and keep a pencil at the same location on its circumference as it rolls. You'll get a cycloid. Just need to compare the equations to the one I gave in the article to be sure you use the right parameters. You might also want to try: www.runet.edu/~tmcmilla/cycloids/Web/cycloidsAbout_Cycloids.html for a freeware program that draws cycloids. I'm not sure if this will help - since it focuses more on artistic renderings than on the sort of graphic you would need for the dial. Fred Sawyer
