CORE DRILLS - STRAIGHT SHANK
Core Drill - 3 Flute - Straight Shank
page 88
Straight Shank Three Flute Core Drills have more chip clearing than four flute core drills. They are used for deep holes and for holes requiring substantial enlarging.
Core Drill - 4 Flute - Straight Shank
page 88
Straight Shank Four Flute Core Drills have a better surface finish than three flute core drills and can be run at higher metal removal rates. They are used for holes requiring light to medium enlarging. Most users find them easier to re-sharpen and measure.
CORE DRILLS - REGULAR MT SHANK
Core Drill - 3 Flute - Morse Taper Shank
page 89
Regular MT Shank Three Flute Core Drills have more chip clearing than four flute core drills. They are used for deep holes and for holes requiring substantial enlarging.
Core Drill - 4 Flute - Morse Taper Shank
page 89
Regular MT Shank Four Flute Core Drills have a better surface finish than three flute core drills and can be run at higher metal removal rates. They are used for holes requiring light to medium enlarging. Most users find them easier to resharpen and measure.