Tech Talk
What is a "Twist Drill"?
The most common type of drill, having one or more cutting edges, and having helical grooves adjacent thereto for the passage of chips and for admitting coolant to the cutting edges. Twist drills are used either for originating holes or for enlarging existing holes. Standard twist drills come in fractional sizes from 1/16" to 1 1/2", wire gage sizes from 1 to 80, letter sizes A to Z, and metric sizes.