Gun Drill Breakage Analysis: How to Read a Broken Drill
I examine every broken gun drill to figure out what went wrong. A broken drill is not trash — it is evidence. The break pattern, the fracture surface, and the location of the break all tell you something about the cause. I have learned more about deep hole drilling from examining broken tools than from any textbook. Problem Description Gun drills break for many reasons, but the break itself is the end result of a chain of events. The drill does not snap spontaneously. Something causes the load to exceed the strength of the drill body. The break pattern preserves information about what that something was. ...