Why do I center drill?

We center drill holes because twist drills are designed to flex (or “wander”) before beginning to cut. Center drills are much stiffer, ensuring that you start cutting a hole in the accurate, desired location. Center drilling also allows you to create a contact point to support the work in the mill. Having a part that sticks too far out of the lathe encourages bending, which could interfere with your cut. By using a center drill, you can put in a live center and the part can still rotate around with decreased risk of bending. For more information, click here.