Kennametal: Beginner’s Guide to End Mills

If you are new to machining, you might be wondering what an end mill is. An end mill is a type of cutting tool that is used in milling applications. It is a rotating tool that is used to remove material from a workpiece. End mills are usually made of high-speed steel (HSS) or carbide and come in a variety of shapes and sizes. They are available in solid and indexable milling styles

The end mill is named after its cutting end or tip, which is shaped like a cylinder or ball at the end of a long shank. They feature several end types for cutting, flutes, and point angles.

End mills are commonly used in milling machines, which are machines that use rotary cutters to remove material from a workpiece. The milling machine moves the workpiece against the rotating end mill, which cuts into the material and removes chips of material to create a desired shape.

End mills are versatile tools that can be used to cut a variety of materials, including metal, plastic, wood, and composites. They are used in a variety of industries, including manufacturing, aerospace, and automotive.

Understanding the Different Types of End Mills is an essential part of learning how to mill. End mills come in a variety of shapes and sizes, each designed to perform a specific type of milling operation. Here are some of the most common types of end mills and their uses:

• Square End Mills: These end mills have a square tip and are used for general milling applications. They are great for creating square bottomed slots and pockets, and for cutting flat surfaces.
• Ball End Mills: These end mills have a rounded tip and are used for milling curved surfaces. They are great for creating rounded edges and for making 3D shapes.
• Corner Radius End Mills: These end mills have a rounded corner on the tip and are used for milling rounded corners. They are great for creating fillets and for making parts with rounded edges.
• Chamfer End Mills: These end mills have a flat tip with angled sides and are used for creating chamfers or beveled edges. They are great for creating angled edges on parts and for creating a finished edge on a part.
• Roughing End Mills: These end mills have a serrated or scalloped edge and are used for removing large amounts of material quickly. They are great for roughing out parts and for creating a rough finish on a part.
• Tapered End Mills: These end mills have a tapered tip and are used for creating tapered holes or channels. They are great for creating parts with a conical shape.
• Drill Mills: These end mills are designed to drill holes and mill flat surfaces at the same time. They are great for creating holes with flat bottoms and for making counterbores.

It is important to choose the right end mill for your project to achieve the desired outcome. Understanding the different types of end mills and their intended uses can help you make the right choice. It is also important to consider factors such as the material being milled, the depth of cut, and the feed rate when selecting an end mill.

Choosing the right end mill for your project is crucial to achieving the desired outcome. Here are some factors to consider when selecting an end mill:

• Material: The material being milled is a critical factor in determining the type of end mill to use. Harder materials, such as metals and alloys, require a harder and more durable end mill, such as carbide, while softer materials, such as plastics and wood, require a softer end mill, such as high-speed steel.
• Cutting Diameter: The cutting diameter of the end mill refers to the size of the cutting surface. Choosing the right diameter is important to ensure efficient cutting and a smooth finish. Smaller diameters are best for detailed work, while larger diameters are better for roughing out material quickly.
• Flute Count: The number of flutes on an end mill affects its cutting performance. End mills with fewer flutes are more rigid and can remove material faster, while end mills with more flutes provide a better finish.
• Coatings: End mills can be coated with various materials, such as titanium nitride or diamond-like carbon, to increase their durability and lifespan. Consider the type of material being milled and the desired finish when choosing a coating.
• Cutting Speed and Feed Rate: The cutting speed and feed rate refer to how fast the end mill is moving through the material and how much material is being removed per pass. Choosing the right cutting speed and feed rate is important to ensure efficient cutting and prevent damage to the end mill and the material being milled.

Consider factors such as material, cutting diameter, flute count, coatings, and cutting speed and feed rate when selecting an end mill. By taking the time to choose the right end mill for the job, you can ensure efficient cutting and a high-quality finish.

Using end mills can be a challenging task for beginners, but with the right tips and techniques, it can be a rewarding experience. Here are some tips and techniques to help beginners use end mills effectively:

• Secure the Workpiece: Before using an end mill, it is essential to secure the workpiece to prevent it from moving during milling. Use clamps, a vise, or other holding devices to ensure the workpiece is stable and secure.
• Choose the Right Speed and Feed Rate: The speed and feed rate at which the end mill is moving through the material affect the quality of the cut. Use the recommended speed and feed rate for the material being milled to ensure efficient cutting and a smooth finish.
• Use the Right Cutting Depth: The cutting depth refers to the amount of material being removed per pass. It is essential to use the right cutting depth to prevent the end mill from overheating and breaking. A good rule of thumb is to remove no more than half the diameter of the end mill per pass.
• Clear Chips Often: Chips can build up on the cutting edge of the end mill, affecting its performance. Clear chips often using compressed air or a chip brush to ensure efficient cutting and prevent damage to the end mill and the workpiece.
• Lubricate the End Mill: Lubricating the end mill can help reduce friction and prevent overheating, prolonging the life of the tool. Use a cutting fluid or oil to lubricate the end mill and prevent it from overheating.
• Test the Cut: Before milling the entire workpiece, it is essential to test the cut on a small section to ensure the end mill is working correctly and to adjust the speed, feed rate, and cutting depth as needed.

Using end mills can be a rewarding experience for beginners with the right tips and techniques. Secure the workpiece, choose the right speed and feed rate, use the right cutting depth, clear chips often, lubricate the end mill, and test the cut before milling the entire workpiece. By following these tips and techniques, beginners can use end mills effectively and achieve high-quality results.

This content was first published on the Kennametal website.