5.1 CHIP FORMATION

---

There are three types of chips that are commonly produced in cutting,

- discontinuous chips

- continuous chips

- continuous with built up edge

A discontinuous chip comes off as small chunks or particles. When we get this chip it may indicate,

- brittle work material

- small rake angles

- coarse feeds and low speeds

A continuous chip looks like a long ribbon with a smooth shining surface. This chip type may indicate,

- ductile work materials

- large rake angles

- fine feeds and high speeds

- use of coolant and good chip flow

Continuous chips with a built up edge still look like a long ribbon, but the surface is no longer smooth and shining. This type of chip tends to indicate,

- high friction between work and tool causes high temperatures that will occasionally weld the chip to the tool. This will break free, but the effects is a rough cutting action.

Continuous chips, and subsequently continuous cutting action is generally desired.