Union Butterfield 3306E(UNC) High-Speed Steel Thread Forming Tap, Extra-Long, Uncoated (Bright) Finish, Round Shank With Square End, Bottoming Chamfer, H5 Tolerance, 6" O'all Length, 3/8"-16 Thread Size

The Union Butterfield 3306E(UNC)/3306E(UNF) uncoated, high-speed steel thread forming tap has an extended round shank with a square end, lubricant grooves, and a bottoming chamfer, and is used for cold-forming right-hand threads in ductile materials such as aluminum, brass, bronze, low-carbon steel, and leaded steel. It is available in two different ANSI thread specification standards: UNC (Unified Coarse) and UNF (Unified Fine). The bottoming chamfer makes it most suitable for threading blind or bottoming holes (with only one opening). The extension Rol-Form design is extra-long for extended reach, with lubricant grooves to improve coolant flow.

High-speed steel (HSS) is a common general-purpose steel for cutting tools and is compatible with a variety of materials. With no coating or surface treatment, this uncoated tool can be used on a broad range of materials and provides an economical alternative to coated tools. The square end shank helps to minimize rotation in the tool holder. This thread forming tap can be used in machines such as drill presses or lathes.

In the Union Butterfield 3306E(UNC) and 3306E(UNF) series, all taps have bottoming chamfers. This tap conforms with ANSI standards and can create threads to a depth 2 ½ times its diameter. It is suitable for the ANSI 2B tolerance class: 2B is an average quality fit for commercial and industrial fasteners.

Taps produce internal threads in previously formed holes and can be used in machines (such as drill presses) or with hand tools. Common types of taps include hand taps, spiral point taps, spiral flute taps, thread forming taps, and pipe taps. Hand taps (straight-flute taps) collect chips in the straight flutes of the tool; spiral point taps push chips through holes ahead of the tool; and spiral flute taps pull chips back from the tip of the tool, up and out the hole. Thread forming taps, also known as cold forming taps, press rather than cut to create threads in a drilled hole, and no chips are created. Pipe taps create threads in pipes and pipe fittings. Each thread type designates a thread profile and each type is identified with an abbreviation. In the U.S. and Canada, the Unified Thread Standard is the dominant thread type, including UNC (Unified Coarse), UNF (Unified Fine), and NPT (National Pipe Taper) threads, among others.

Precision Dormer manufactures cutting tools under the following brands: Precision Twist, Dormer, and Union Butterfield. The company has locations around the world, and provides tools adhering to ANSI, NAS, and DIN standards.