7/8" x 9 HSS Cobalt BSW Spiral Point Tap

About this item:

• 7/8" x 9 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.