Sources and scope for this page: Industry convention — no single governing standard (conventional usage, definitions vary between sources), covering the definition of slotting (full-width cut). 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
Slotting is the hardest common milling operation because the chip has to be evacuated from a closed channel. Recutting an already-cut chip is the main cause of poor finish and rapid wear, and the problem gets worse with more flutes because there is less chip room.
The standard responses are to use fewer flutes, to reduce the feed, or to rough the slot with a smaller cutter and finish it with a full-width pass.
Common misuse
Slotting with a four-flute cutter because it works well for profiling. Profiling gives the chip an open side to escape; slotting does not.