Dormer E550 High-Speed Steel Pipe Tap Set, Uncoated (Bright) Finish, Round Shank with Square End, 2-Piece (1 Plug and 1 Bottoming Chamfer), 1/8"-28 Thread Size

The Precision Twist E550 is a BSPT internal thread, machine tap made of HSS with a bright finish. It can create threads at a depth of one and one-half times its diameter. The semi-bottoming chamfer helps guide the starting of the tap. Good for tapping a wide range of metals with best performance in cast iron and copper. It conforms to ISO 2284 standards .If you are creating a blind, or bottoming hole (a hole that does not go completely through the material), then you would use the plug tap to start the hole. The greater chamfer allows for easier starting. To maintain correct perpendicular alignment with the work piece, use the bottoming tap (sometimes called semi-bottoming chamfer) to create the last threads in the hole. For a through hole, you only need the plug tap. The E550 series has a semi-bottoming chamfer with two or three threads at the start of the tap. A right-hand thread means that it needs a right-hand, or clock-wise, rotation to tighten it. A tap is a cutting tool used to create screw threads, which is called tapping. A tap cuts a thread on the inside surface of a hole, creating a female surface which functions like a nut. Dormer Pramet manufactures cutting tools under the following brands: Precision Twist Drill, Dormer, Union Butterfield and Pramet. The company has locations around the world, and provides tools adhering to ANSI, NAS, and DIN standards.

• British Standard Pipe Taper thread (BSPT) machine tap, used to create BSPT standard threads
• Used in through or blind holes
• Straight flute, parallel internal thread, creates right-hand threads
• Uncoated (bright), economical and useful with a wide range of materials
• High-speed steel (HSS), for use on a wide variety of materials