Key Features

• Square nose end mills (also called square end) create sharp, unrounded cuts
• Four flutes produce a better finish than fewer flutes
• Titanium nitride (TiN) is a general-purpose coating that combines high-temperature resistance and increased hardness compared to uncoated end mills
• High-speed steel is compatible with a variety of materials
• Center-cutting design allows the end mill to plunge into material like a drill bit while also performing conventional surface milling

Product Description

The Union Butterfield TN945 TiN-coated high-speed steel square end mill has four flutes and a 30-degree helix angle for general-purpose machining on a range of materials. The four flutes provide a better finish than fewer flutes. The general-purpose TiN coating combines stability at high temperatures with hardness for wear protection, increasing tool life and performance compared to uncoated end mills. (TiN is suitable for a range of materials, but uncoated end mills are recommended for machining aluminum.) High-speed steel (HSS) is a common general-purpose steel for cutting tools and is compatible with a variety of materials. The tool’s square end creates sharp, unrounded cuts.

The 30-degree helix angle supports general-purpose applications. It balances lower angles’ strong cutting edge for difficult-to-machine materials with higher angles’ increased cutting edge. The center-cutting design has cutting teeth at the end of the tool, so it can be fed into the workpiece like a drill bit; it can also be used for slotting and ramping. The cutting diameter tolerance is +0.003” to -0.000”. This tool has a Weldon shank that provides a secure hold in the toolholder and helps prevent slippage. It meets ANSI specification B94.19 for quality assurance.

End mills are designed to remove material and create multi-dimensional shapes and profiles. They have cutting edges along the outside diameter and flutes that remove chips from the cutting area and allow cooling fluids to enter. If heat is not reduced effectively, the tool’s cutting edges will dull and additional material buildup can occur. The number of flutes can range from two to eight. Two-flute designs offer the most efficient chip removal, but more flutes provide a smoother finish. The shank is the end of the tool held in place by a tool holder or machine. Center-cutting end mills can create three-dimensional shapes and profiles, and make plunge cuts similar to a drill bit. Non-center-cutting end mills are for applications such as peripheral milling and finishing, but cannot make plunge cuts.

Precision Dormer manufactures cutting tools under the brands Precision Twist, Dormer, and Union Butterfield. The company has locations around the world, and makes tools that meet to ANSI, NAS, and DIN standards.