End Mills for Precision Machining
Publiée le 12.10.2022
End mills are essential tools for precise milling operations on various materials such as stainless steel, precious materials, titanium, and aluminum. The choice depends on the characteristics of the material to be machined and the desired application. Using the appropriate end mill ensures precise cutting, optimal finishing, and extends the tool's lifespan.
How to Choose the Right End Mill?
Choosing the right end mill requires considering several criteria based on the work to be done and the type of material to be machined. Here are the main elements to consider.
Material of the End Mill
End mills are available in various materials, each with specific advantages. Solid carbide end mills, made from tungsten carbide particles and micrograin, are particularly suited for intensive milling operations requiring high wear resistance. HSS (high-speed steel) end mills, on the other hand, offer greater flexibility and are suitable for softer materials or low-speed work.
Shape and Geometry of the End Mill
The shape and geometry of the end mill directly influence the quality of the cut. There are cylindrical end mills, ideal for straight cuts, and ball nose end mills that allow precise 3D work. Conical end mills are also common for operations requiring a more specific shape or fine finishes on complex pieces.
Diameter and Cutting Length
The diameter of the end mill and its cutting length determine the depth and precision of cuts. A small diameter allows detailed work, while a larger diameter ensures quick cutting. The length of the end mill, measured in millimeters, must be adapted to the thickness of the workpiece to avoid vibrations and ensure a smooth finish. It is also important to consider the design of the end mill, especially for long or complex tasks.
Type of Coating
End mills can be coated with various materials to increase their durability and improve performance. We offer a wide range of coatings, designed to optimally adapt to each application and type of material.
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Types of End Mills for Different Materials
Depending on the material to be machined, some end mills will be more suitable than others. Here are the main recommendations based on the most common materials.
End Mills for Steel and Stainless Steel
Carbide end mills are particularly effective for machining hard materials like steel and stainless steel. Their heat resistance and rigidity allow prolonged milling operations with minimal wear, ensuring a high-quality finish.
Roughing End Mill: Geometry 21046, 21525, 21535, and geometry with peripheral cooling 29510 coated EZI-ALPHA 3
Finishing End Mill: 21036, 21302 coated EZI-ALPHA 3
Torical End Mill: 21071 coated EZI-ALPHA 3
These tool ranges are also available with central cooling from a diameter of Ø1 mm, enhancing performance and tool lifespan while ensuring better surface finishes.
End Mill for willemin-macodel 701S: 24036, 24302, 24071 coated EZI-ALPHA 3
End Mills for Aluminum
Aluminum being a softer material, end mills designed for aluminum often have specific geometries to prevent clogging, notably with rake angles or wider flutes. These end mills allow a clean cut without material sticking to the tool, ensuring a standard result for such work.
Roughing End Mill: Geometry 21602, 21603
Finishing End Mill: Geometry 21026, 21027, 21126, 21325, 21326
These geometries are all available with optimized coatings for aluminum machining.
End Mills for Composite Materials
For composite materials, it is important to use end mills with an optimized cutting angle to achieve a smooth surface and prevent chipping. Helical end mills are often recommended for these tasks, ensuring a clean and precise cut. In some configurations, end mills with serrations can be used to improve grip during cutting.
Roughing End Mill: Geometry 21046 coated EZI-ALPHA 3
Finishing End Mill: 21036, 21302 coated EZI-DIAM
Super Finishing Milling: 21112, 21105 coated EZI-DIAM
Torical End Mill: 21372 coated EZI-DIAM
End Mill for willemin-macodel 701S: 24036, 24302, 24071 coated EZI-ALPHA 3
End Mills for Titanium
Titanium is a demanding material due to its high resistance and heat sensitivity. End mills designed for titanium are often made of carbide, with optimized geometries to minimize heat generation during cutting. It is recommended to use specific coatings, such as titanium nitride (TiN) or zirconium nitride (ZrN), which help reduce friction and prolong tool life. Moreover, adequate cooling and reduced cutting speeds are essential to prevent deformation and ensure a high-quality finish.
Roughing End Mill: Geometry 21046, 21525, 21535, and geometry with peripheral cooling 29510 coated EZI-ALPHA 3
Finishing End Mill: 21036, 21302 coated EZI-ALPHA 3
Super Finishing Milling: 21065, 21111, 21112 coated EZI-ALPHA 3
Torical End Mill: 21071 coated EZI-ALPHA 3
End Mill for willemin-macodel 701S: 24036, 24302, 24071 coated EZI-ALPHA 3
These tool ranges are also available with central cooling from a diameter of Ø1 mm, enhancing performance and tool lifespan while ensuring better surface finishes.
End Mills for Precious Materials (Gold, Platinum)
For machining precious materials such as gold and platinum, it is crucial to use end mills specifically designed for these applications. Tungsten carbide end mills with fine sharpening and adapted geometry are ideal for ensuring precise cutting while preserving the material's value. Using a PVD (physical vapor deposition) coating can also enhance tool durability and reduce metal particle adhesion on the end mill. Due to the delicate nature of these materials, strict control of machining parameters, such as cutting speed and feed rate, is essential for achieving a flawless finish without damaging the final product.
Roughing End Mill: Geometry 21510, 21520, 21525, 21535, and geometry with peripheral cooling 29510 coated EZI-ALPHA 3
Finishing End Mill: 21030, 21031, 21032
Torical End Mill: 21071, 21072
These tool ranges are also available with central cooling from a diameter of Ø1 mm, enhancing performance and tool lifespan while ensuring better surface finishes.
End Mill for willemin-macodel 701S: 24036, 24302, 24071
Comparison of the Most Popular End Mills
Comparing different types of end mills allows for better selection according to the specific needs of each operation.
Comparison of Carbide vs. HSS End Mills
Carbide End Mills:
Advantages: high wear resistance, extended lifespan, excellent for precision work and hard material machining.
Disadvantages: more fragile, can break under shock or mishandling, higher initial cost.
Price: more expensive, but a worthwhile investment for demanding applications.
HSS (High-Speed Steel) End Mills:
Advantages: great flexibility, good impact resistance, more affordable price, suitable for softer materials or low-speed machining.
Disadvantages: wear out faster than carbide end mills, less effective for hard materials.
Price: more economical for standard tasks or softer materials.
Single-Cut vs. Double-Cut End Mills
Single-Cut End Mills:
Performance: good for less precise work, suitable for roughing or softer materials like wood or aluminum.
Applications: ideal for quick cuts but may lack precision on harder materials.
Double-Cut End Mills:
Performance: provides better finishes, ensuring cleaner and more precise cuts.
Applications: perfect for precision work, especially in harder materials like steel or stainless steel, or when a high-quality finish is required.
How to Properly Use an End Mill?
To get the most out of your end mill and extend its lifespan, here are some practical tips.
Optimal Cutting Speed and Feed Rate According to Material
The cutting speed must be adapted to the material being worked on. A speed too high in a hard material can lead to premature tool wear, while a speed too low can reduce cutting efficiency.
Tips to Avoid Breaking the End Mill
Using an appropriate speed and feed rate and choosing an end mill with a diameter and length suited to the workpiece helps prevent premature tool breakage.
Common Machining Problems and How to Avoid Them
Common issues include excessive tool wear, vibrations, or flute clogging. Using a coated end mill and maintaining a proper cutting speed are effective ways to limit these problems.