Sutton M2454826 1-1/2" x 11-1/2 NPT Bottoming Hand Tap - Straight Flute, TCA

The Sutton M245 is an NPT (National Pipe Taper) bottoming hand tap in 9 sizes, 1/8" to 2", with a straight flute and a square shank, made from Tungsten Chrome Alloy (TCA) and sold singly. It cuts internal NPT taper pipe threads in pipes and is suited to pipe fittings. A bottoming tap offers a continuous cutting edge with almost no taper and is usually used to cut threads to the bottom of a blind hole.

The square shank is designed for hard threading work in a variety of materials. The straight flutes suit through-hole tapping. Carbon taps are not suitable for precision, safety or critical threads. They are for general purpose and DIY use only. Applications include DIY, trade, automotive, plumbing, metalworking and MRO work. The tap has a 15 chamfer.

Where this product is used

• Cutting internal NPT taper pipe threads in pipes and pipe fittings.
• General purpose and DIY plumbing and workshop threading where a precision thread is not required.
• Applications include DIY, trade, automotive, plumbing, metalworking and MRO work.

Design features

• Tungsten Chrome Alloy (TCA): carbon taps for general purpose use.
• Square shank: for hard threading work in a variety of materials.
• Straight flutes: suited to through-hole tapping.
• Lead: A bottoming tap offers a continuous cutting edge with almost no taper and is usually used to cut threads to the bottom of a blind hole.

Sizes and item numbers

Tap drill is the drill size to use before tapping.

Using the tap

• Drill the tap drill size shown in the size table for the thread you are cutting, then start the tap square to the hole.
• Turn the tap with a tap wrench on the square shank, backing off regularly to break the chip.
• Use a cutting fluid suited to the material being tapped.
• Confirm the thread standard of the mating fitting before tapping: BSP threads have a 55° thread angle and NPT a 60° thread angle, and they are not interchangeable.
• G series (BSPF) threads are parallel; Rc (BSPT) and NPT threads are taper threads. Check the fit against the mating part as you tap.

Key specifications

Related products

Related Sutton threading tools: M244 BSPT bottoming taps, M240 BSPF taper taps, M241 BSPF intermediate taps and M242 BSPF bottoming taps. Browse threading tools and threading dies and sets, or Tap Magic cutting fluids.