A milling cutter with flutes running up its side and cutting edges on the end, made of carbide, high-speed steel or cobalt steel. Two or three flutes suit aluminum, where chip room matters, and four or more suit steel. End shapes include square, ball nose and corner radius, and center-cutting endmills can plunge straight down like a drill.
Use a three-flute endmill for the aluminum, the four-flute will pack chips and weld up.
Flute count is about chip room as much as finish: fewer flutes to clear gummy aluminum, more flutes for strength and finish in steel.
Also heard as
- end mill
Related terms
Collet
A slotted, tapered sleeve that squeezes evenly around a tool shank or bar stock to grip it accurately.
Chatter
Self-sustaining vibration between tool and work that screams, leaves a wavy pattern and kills tools.
Hog out
To remove a large volume of material fast with heavy roughing cuts, without worrying about finish.
Feeds and speeds
The spindle speed and feed rate chosen for a cut, set from material, tool and machine.