Machine Nut & Long Series Taps

MACHINE NUT (BS949) These taps were designed for tapping nuts on machines, and have a long thread, shank and square length. The shank diameter is reduced below the thread minor diameter to enable the tap to run through the work piece. This was originally to allow nuts to collect on the shank. For nut production, taper leads were used to distribute the cutting action, but these taps are now generally used as long reach, and are supplied also in bottom and second leads.