Which drill bit for which material?

Which drill bit for which material?

DIN 1836 divides spiral drills into these three types N, H and W.

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Type N: Spiral angle 19° - 27° for normal-hard materials such as general structural steels, cast iron, and non-ferrous metals.

Type H: Spiral angle 10° - 19° for hard, short-acting and brittle materials such as steel, brass, bronze, magnesium alloys, hard plastics or laminates.

W type: Spiral angle 27° - 45° for soft, long-cutting and tough materials such as aluminum, copper, zinc or soft plastics.

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