Zurück zu: Facts

Twist drills - Definitions

Twist drill with straight shank / taper shank Cutting portion Angles on the cutting edges Special point grinds Reference to other relevant standards

Twist Drill with Straight Shank/Taper Shank

Cutting portion

In the context of cutting technology, land width b is the body clearance land width which is to be denoted by balpha; see DIN 6581.

Angles on the cutting edges

The corder has been adopted as the observed edge point. Clearance angle alpha, wedge angle beta and the rake angle gamma are measured in the tool orthogonal plane. For details, see DIN 6581, definitions of metal-cutting technology; geometry at the tool edge.

Special point-grinds

Form A Thinned chisel edge Form B Thinned chisel edge with corrected cutting lips Form C Split point Form D Point ground for cast iron Form E Brad point (center point)

Reference to other relevant standards

DIN 228 Part 1 Machine tapers; Morse tapers and metric tapers, taper shanks DIN 232 Form of transition from taper shank to cutting portion of tool; directions DIN 1414 High speed steel twist drills; directions for design and use DIN 1453 Part 1 Greek lettering, hand-written styles for use in formula in drawings for making blocks and diapositives DIN 1453 Part 2 Greek lettering, hand-written styles for use in constructional drawings and signatures DIN 6580 Definitions of the metal-cutting industry; motions and geometry of the cutting process DIN 6581 Definitions of the metal-cutting industry; geometry at the tool edge The standard descriptions above are given with permission from the German Standards Institute (Deutsches Institut für Normung). The most recent editions of the standard sheets apply and are available in DIN A4 formats from Beuth-Verlag GmbH, D-10787 Berlin.

Back to top