5/16" x 18 BSW Bottoming Left Hand HSS Tap - Goliath

About this item:

• 5/16" x 18 BSW Bottoming Left Hand HSS Tap - Goliath
• LEFT HAND HSS Bright Finish BSW Hand and Machine Bottoming Tap.
• HSS Straight Flute Short Machine and Hand Taps.
• These general purpose taps are ideal for creating new threads in a wide variety of materials.
• Goliath HSS taps provide a high hardness to toughness ratio, compressive and tensile strength, good abrasion resistance and resistance to micro-chipping, ensuring a long tool life.
• British Standard Whitworth angle of thread is 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.
• Bottoming Taps have a lead of two threads and are used to ensure minimum thread run-out when tapping to the bottom of a blind hole.
• Bottoming Taps are typically preceded by the use of a Taper or Intermediate Tap.
• Manufactured from HSS this general purpose tap is designed for use in medium tensile materials and is for hand or general machine use.