Website last updated 03 August, 2010

K Scale

The K scale allows finding cubes and cube roots, when used in conjunction with C or D. Unlike AB or CD pairs, most slide rules will have only one copy of K, found on the stock, if they have it at all. But you can add K's to both the stock and the slider if you like.

read the tutorial on squaring, cubing, and roots
The K scale is a C or D scale, shrunk to 1/3 its length and copied twice, with values 10x and 100x higher. This marks off the cubes of the numbers on D. We call 1 to 10 the left decade, 10 to 100 the middle decade, and 100 to 1000 the right decade. As with the A and B scales, it's easy to find the coefficient of cubes and cube roots with K, but more care must be taken to determine the correct power of ten( decimal point ).
The warning about multiplication using A and B scales applies equally to using 2 K scales to multiply. The precision will be even less.