>RE: Reuleaux Triangle drill > Someone said here (I think it may have been M. Keyton) >that there was a real drill using the principal >of the Reuleau triangle. I am curious how that is driven. As well as >I can understand this operation the shank or shaft that drives the triangle would have to move in a four leaved rose pattern as the drill >rotates and still provide rotational force.
In Martin Gardner's article "Curves of Constant Width", in his compendium of some of his Sci Am articles, Further Mathematical Diversions (ISBN0 04 793015 22), he states:
"In 1914, Harry James Watt ... invented a rotary drill based on the R triangle and capable of drilling square holes! Since 1916, these curious tools have been manufactured by the Watts Brothers Tools Works in Wilmerding. PA. ... A metal guide plate with a square opening is placed over the material to be drilled. As the drill spins within the guide plate, the corners of the drill cut the square hole through the material. A patented 'full floating chuck' ... does the trick (US patents 1,241,175,..)."
So it appears that the chuck moves more or less freely, and presumably centrifigal force aids in determining the position of the chuck at a given instant. The original article was published in 1961-63, I wonder if the Watts Brothers Tool Company is still in existance?
Re (uleau)x ***
Rex Boggs | High above the hushed crowd, firstname.lastname@example.org | Rex tried to remain focused. | Still, he couldn't shake one Glenmore High School | nagging thought: He was an Rockhampton, Quensland | old dog and this was a new Australia | trick - Gary Larson