Tools & Gear Taps & Dies HSS-Co5 Machine Taps

3128-3/4 3/4" x 10 HSS Cobalt BSW Spiral Point Tap HSS-Co5 (Cobalt) BSW Spiral Point (Gun Nose) machine tap. Cobalt HSS taps are extremely hard and provide superior performance and increased tool life especially in stainless steel and high tensile steel. Gun nose taps have straight flutes supplemented by angular cutting faces at the lead. The design of the cutting portion propels the swarf ahead of the tap leaving the flutes clear for the flow of coolant to the cutting teeth. Primarily designed for use in through holes, these taps can be used in blind holes provided that there is ample clearance beyond the threaded section to accommodate the swarf. The advantages of a gun nose tap are the shearing action of the angular cutting faces, which produces a fine finish on the threads and shallower flutes. This allows a stronger cross section throughout the tap. British Standard Whitworth has a thread angle of 55 degrees as opposed to 60 degrees in Metric and Unified threads. This thread form was developed by Sir Joseph Whitworth in 1841. The thread form has rounded roots and crests and is specified in BS84:1956.