Chapter 12, Problem 13A

The length, L, of the point on any standard 118° included angle drill, as shown in Figure 12-5, can be calculated using the formula $L=0.3\text{<menclose notation="updiagonalstrike"> <mn> O </mn> </menclose>}$ where ∅ represents the diameter of the drill. Determine the lengths of the following drill points with the given diameters. Round to 3 decimal places for inches and 1 decimal place for millimeters.

a. $\frac{1\text{'}\text{'}}{2}$
b. $\frac{1\text{'}\text{'}}{4}$

c. $\frac{3\text{'}\text{'}}{8}$
d. 10 mm
e. 25 mm
f. 45 mm