Originally Posted by st3v3
Originally Posted by PatrickSwe
Originally Posted by crash_ash
easy way to remember, if your tap says M12 x 1.75 for example subtract the 1.75 from the 12 to give the tap drill size, in this case it'd be 10.2mm
Correct!
ps,
Working as cnc operator in sweden, drills a lot of holes and thread´s them
ds.
Not always true for Imperial pitches though

but normally we dont say the pitch of the imperial threads we say the teeth per inch, and of cause to work out thread depth from TPI you need the thread angle as well! i know you know this and thats why you said it though