Chamfer Type

Chamfers are the tapered or incomplete threads at the front of the tap.

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  Bottoming chamfers have 1 to 2 tapered threads and are only used in blind holes where the threads must come as close to the bottom of the hole as possible.

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  Modified Bottoming chamfers have 2-1/2 to 4 tapered threads and are used in through holes and holes where there is sufficient room at the bottom. These are usually found only on high performance taps.

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  Plug chamfers have 3 to 5 tapered threads and are used in through holes and holes where there is sufficient room at the bottom.

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  Semi-Bottoming chamfers have 2 to 2-1/2 tapered threads and are used in blind holes where slightly more length is needed than a standard bottoming chamfer. These are usually found only on high performance taps.

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  Taper chamfers have 7 to 10 tapered threads and are used for starting threads and for through holes.