2012/2013 Power Tools & Accessories Catalog | 149 Black Oxide Taps and Dies
Heat-treated carbon steel
provides long life and clean,
accurate threads
Rolled threads provide more accuracy than machined threads
Black oxide coating provides corrosion resistance
Laser-etched marking
ensures size identification won't wear off
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Product Info — Tap Point Styles Taper
Taper
f 8–10 chamfered threads at the tip ideal for starting threads in tough materials
f Longest chamfer of all three types
f Commonly used in through holes and with materials where a guide is necessary
f Requires less torque due to more working teeth
Plug Plug (most widely used)
f General purpose tap, with 3–5 chamfered threads
f Used when there is sufficient room on a blind hole and tapping
to the bottom is not required Bottoming Bottoming
f Used after the threads have been started
f 1–3 chamfered threads at the tip are enough to start the hole and taps all the way to the bottom
Toll free: 877-BOSCH-99
Note: Tap and die size is indicated by two numbers. The first number represents the diameter of the screw or bolt. The second number represents threads per inch. The letters after the tap size indicate particular screw or bolt standard:
NC = National Coarse NF = National Fine NS = National Special NEF = National Extra Fine NPT = National Pipe Taper BSP = British Standard Pipe D.I.N. = French International Standard
Example: A 1/4-20 NC tap will cut 1/4" outside diameter with 20 threads per inch for a National Coarse-type screw.