Is it easy to break a tap, drill, or end mill?

(How do they break, and what does it look/sound like if one breaks?)

Breaking a tap, drill or end mill is common. The most common causes for breakage are chip build-up, lack of lubrication, or improper tool usage. To avoid breakage, make sure to

• Employ the correct feed rate with harder materials

• Use end mills with less flutes for soft materials

• Use end mills with more flutes for hard materials

• Don’t use cutting tools that are longer than necessary (beam bending).

Because taps, drills, and end mills are slender and made of hard, brittle materials, it should be obvious if one breaks. They are most likely to make a quick snapping noise and break perpendicular to the long axis. Here are some tips to avoid breakage.