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Internal thread profile

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METRIC THREAD

Example : M5 X 0.8

Tap drill size = Major Dia - pitch

Tap drill size = 5.0 – 0.8

Tap drill size = Ø 4.2 mm

If drill size not available, Select the next larger standard drill size.

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INCHES THREAD

Example : 1/2 X 13 UNC – 2B

Tap drill size = 0.5” – 0.07692”

Tap drill size = 12.5 – 1.9538

Tap drill size = Ø 10.5 mm

If drill size not available, Select the next larger standard drill size.