Sources and scope for this page: Industry convention — no single governing standard (conventional usage, definitions vary between sources), covering the definition of peck drilling. No independent source check is recorded for this page: the content rests on the sources listed and on the working shown on the page. How sources, methods and updates are recorded.
Definition
Deep holes trap chips, and a trapped chip is what breaks drills. Pecking clears them, at the cost of cycle time and of repeatedly re-entering a hole that may have work-hardened at the bottom.
The rough rule is to peck once depth exceeds about three diameters in steel. In gummy materials peck sooner; in free-machining grades with good chip formation you can go deeper.
Common misuse
Pecking too aggressively on stainless or titanium, which work-hardens the hole bottom each time the drill re-enters and rubs before it cuts.