Drill America 3 mm - 12 mm Round Dies High Speed Steel NC and NF Tap and Die Set (40-Pie

3 mm to 12 mm High Speed Steel NC and NF Tap and Die Set with Round Dies in plastic case. Set also includes 2 straight tap wrenches. Full sizes included: 3 mm 4 mm 5 mm 6 mm 7 mm 8 mm 10 mm 11 mm 12 mm. About High Speed Steel Taps: Hand Taps are the most versatile taps for hand use or for tapping under power. Hand taps are popular for use in general machine tapping or CNC tapping. They are also appropriate for tapping the vast majority of materials in through or blind holed conditions. Taper Style: Starts the thread square with the workpiece. Plug Style: Generally used in thru holes. Bottom Style: Generate the thread to the bottom of the hole. About High Speed Steel Dies: For threading, a High Speed Steel Round Adjustable Die is desired for improved wear life. Round Dies are chamfered on both faces. 1 side has a 2 to 3 thread chamfer for threading, the other side has a 1 to 1-1/2 thread chamfer for threading close to a shoulder. Adjustment is obtained by a fine pitch screw which forces the sides of the die apart or allows them to spring together. The slot is beveled so that when the dies are used in a machine holder the adjusting screw can be removed and adjustment made by the adjusting screws in the holder.