End Milling: Process, Mill Types, And Advantages
What Is End Milling?
End milling is a versatile type of milling that machinist use to produce different shapes on the work piece. Popular shapes from end milling are profiles, die cavities, machine slots, and contours. The tool that performs these cuts is called the end mill. This tool is cylindrical and has cutting edges on the tip and periphery. Therefore, the end mill does both peripheral cutting and end cutting.
The main distinction between end milling and other types of milling is the type of cutting tool. The cutting edges on the end mill are typically helical in design. This design is necessary to minimize the impact between the work piece and the end mill during initial engagement.
How the End Milling Process Work?
A beginner may find it difficult to understand how the end milling process works. However, it all takes identifying the basics of the machining process and some practice to use the method correctly. Here are the main steps to follow when end milling:
Set up the work piece
For you to start end milling and create parts, you need to secure the part on the machine. The milling machine comes with holding devices, for instance, vise and clamps. Use these to secure the work piece firmly so that the milling process proceeds without unnecessary vibrations.
Choose the Milling Operation Tool
There are several types of end mills, but you need to choose from. First, consider the type of material that you want to cut. If you are cutting steel, you want to use a tough end mill. Carbide tools are the best for this material. For aluminum and other softer materials, high speed steel (HSS) end mills may be used.
The next consideration is the depth of cut needed. You don’t need a long end mill when you are cutting only a couple of inches. It will only present vibration challenges and rougher finishes. The price of the end mill may also be a factor, given that some types are more expensive than others.
Set the feed rate and speed
we all know that the speed of cut affects the quality of the resulting surface. Find and use the recommended parameters to get the best surface finish.
Correct cutting depth for End Mill
The cutting depth is the depth of material that the end mill cutting edge removes per pass. You want to stick to the recommended cutting depth. This avoids overheating and breakage of the end mill. The best practice in end mill is to remove up to 50% of the end mill diameter in every pass.
Test the end milling process
Having done these preparations, you are now set for the cutting process. But that is not before you test the end milling. In this test cut, work on a small portion of the work piece to ensure that everything is working as expected. Make the necessary adjustments.
Perform the Process
you can now cut the piece. Remember to activate the coolant so that the work piece and the mill don’t overheat. This helps get the best results and prolongs the life of the cutting tool.
The Purpose of End Milling
With its purported resemblance to other milling processes such as face milling, one may wonder whether end milling serves any purpose. Well, this is one of the most versatile and relevant machining processes.
Machinists who are looking to form complex shapes with detailed contours may not have an alternative. End milling is applicable for a wide range of materials, from plastics to metals. Due to its versatility, this machining process has found applications in different industries.
To add to the versatility advantage, end milling is highly efficient. Its capability to produce parts of complex geometry fast is better than most. It is one of the best methods for users seeking to streamline their production processes.
You can use end milling in different areas. It could be in a process a simple as facing, but you can also do more complex jobs such as surface contouring or slotting. End milling does a splendid job at surface contouring. That’s why they use extensively in the aerospace and automotive industries, where such results are often used.
Users in the detailing and engraving businesses are also fond of end milling. The method is effective in applying intricate details, even serial numbers. You will thus find this process in electronic manufacturing industries and medical engineering.
End milling also finds purpose in drilling projects. This is testament to the unrivalled versatility of end mills. The capability of end milling to drill is essential in processes where the operator needs to cut laterally and drill.
Types of End Mills:
There is a wide range of end mills, with each type being suitable for particular jobs. Here are some of the popular types of end mills:
Square end mills
The defining feature for these end mills is a profile that is at 90 degrees. They are suitable for general milling operations.
Keyway end mills
This type of end mill is used for making keyways. The keyways or grooves are common in rotating machinery, for instance, pulleys. You will mostly find this cylindrical tool in the manufacture of components for aerospace and automotive industrial applications.
Ball end mills
These end mills are also called ball nose end mills. The name is derived from the round shape of the cutting edge. The ball end mills are excellent for milling curved surfaces.
Roughing end mills
The end mills are designed for milling out large chunks of material in one pass. They can be either fine or course pitched. Some users call them hog end mills.
Corner radius end mills
These end mills are meant for cutting particular corners. They come with rounded corners.
Roughing and finishing end mills
This end mill group is capable of providing a smooth surface in one pass.
Corner rounding end mills
These end mills are perfect for milling the round surfaces of a workpiece. The tool comes with a specially hardened tip to prevent tool damage by chipping.
Drill mills
These end mills are designed for countersinking and drilling. You want to avoid drilling steel with these end mills.
Tapered end mills
Finally, there are the tapered end mills, which are good at forming channels or tapered holes. They have a tapered end to make this effective.
Advantages And Disadvantages of End Milling
Like the other milling operations, end mill operations have advantages and disadvantages. Here’s a look at these pros and cons of end mills:
Pros
Suitable for different types of milling operations
Produces high quality finishes
Tool life is long with good selection
Less chatter and vibration with advance processes
Cons
Cutting reach is limited
The best end mills can be too expensive
Abrasive material type causes rapid tool wear
Not suitable for heavy machining due to heat generation
Conclusion
Users, including first-timers, can successfully create parts with end mills. They just need to be armed with the right tools, machines, and approaches. It is important to get it right from the type of end mill chosen, to the amount of feed rate used.
By using the information shared here, we are sure you will enjoy your end milling operations. At our company, we are ready to support you with all your milling operations needs.
Call Aria Manufacturing today for the best end mill and related operations.
Author
Gavin Leo is a technical writer at Aria with 8 years of experience in Engineering, He proficient in machining characteristics and surface finish process of various materials. and participated in the development of more than 100complex injection molding and CNC machining projects. He is passionate about sharing his knowledge and experience.