Re: [oletrucks] tap and dye's 55TF

["Woody" <woodrow@isomedia.com>]

 The general rule of thumb for tap drill size is "Bolt diameter minus one
pitch."  For example, to figure the drill size for a 3/8-16 tap, you would
divide one inch by the number of threads, in this case 16.
This gives a result of .0625 inches.  By subtracting this from 3/8 (.375)
you get .3125 which is equal to 5/16 which is the drill size for 3/8-16.
This works for all V-type threads, including metrics.
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