Question (WOODWEB Member) :
What is the exact formula for the taper on classical round columns? I've heard that the bottom 1/3 is straight and the top 2/3 has a curved taper. I am looking for the precise formula for this top taper - preferably as a ratio so I can apply it to a variety of column sizes. If the 1/3 mark is 10" diameter, what should the diameter be at the top - 9"? I can guess and experiment as well as the next guy but I am hoping that someone reading this has found the exact formula. Iíd rather not reinvent the wheel, or, the column.
(Architectural Woodworking Forum)
From Contributor T:
Usually the taper or entasis starts at 1/3 of the column length measured from the base. The diameter of the top is usually 5/6 of diameter of the base. A lot of these numbers depend on the order (Doric, Tuscan). The book "American Vignola" by William R. Ware has helped me very much in figuring out classical dimensions and proportions.