Common CNC milling tools can be categorized into flat end mills, ball end mills, and bull nose end mills. Micro-drilling with a diameter below 2 nanometers is referred to as micro-drilling. It is often used to describe the pore size of some catalysts. Micro-drilling is challenging, especially for diameters below 1mm, making it highly difficult. However, many mechanical products feature such micro-drilled structures. Mechanical machining refers to the process of changing the dimensions or properties of a workpiece using mechanical equipment. Based on the different processing methods, mechanical machining can be divided into cutting and pressure processing.
Top 3 Types of Milling Tools
CNC machining feed paths refer to the path the tool takes from the reference point (or machine fixed origin) to the end and back, including the cutting path and the non-cutting travel paths like tool entry and exit. Each tool has its specific function, as follows:
Flat End Mill
In CNC machining centers, flat end mills, also known as end mills or face mills, have primary cutting edges around the periphery and secondary cutting edges at the bottom. They can be used for roughing, chamfering, and precision machining of side and horizontal surfaces. Common ones include ED20, ED19.05 (3/4 inch), ED16, ED15.875 (5/8 inch), ED12, ED10, ED8, ED6, ED4, ED3, ED2, ED1.5, ED1, ED0.8, and ED0.5, where “e” represents an end mill, and “d” denotes the cutting edge diameter.
In this case, during roughing, it is advisable to choose tools with different diameters, and the tool length should be kept short to ensure sufficient rigidity and avoid tool deflection. When using smaller tools, the length of the cutting edge and the shank part should be determined based on the machining area to minimize processing time and select the most suitable tool for the company.
Bull Nose End Mill
In CNC machining centers, bull nose end mills, also known as flat R mills, are used for contouring, flat light cutting, and curved surface light cutting. The corner radius generally ranges from r0.1 to r8. They come in solid blade and inserted blade versions. Bull nose end mills with blade textures are also known as fly cutters, mainly used for large-area, thick flat light cutting. Common ones include ED30R5, ED25R5, ED16R0.8, ED12R0.8, and ED12R0.4. During roughing with fly cutters, larger tools should be chosen to process deeper areas, while short tools should be used for shallower areas to improve efficiency and prevent cutting.
Ball End Mill
In CNC machining centers, ball end mills, also known as R mills, are primarily used for curved surface light cutting and curved surface light cutting. Common ones include BD16R8, BD12R6, BD10R5, BD8R4, BD6R3, BD5R2.5 (commonly used for machining channels), BD4R2, BD3R1.5, BD2R1, BD1.5R0.75, BD1R0.5, where “b” stands for a ball mill. For precision machining, measuring the inner circle radius of the processed graphics is essential to determine the tools to be used. It is recommended to select a larger tool, a light-cutting tool, and a smaller tool for supplementary processing.
In metal cutting processes, tool material must withstand significant cutting forces and impacts, intense friction with the workpiece and chips, and high cutting temperatures. The cutting performance of the tool material must be studied based on several factors.
- High Hardness: HRC62 or above, preferably higher than the hardness of the workpiece material.
- High Wear Resistance: Generally, harder materials with more carbon and finer, evenly distributed particles exhibit better wear resistance.
- Sufficient Strength and Toughness
- High Heat Resistance
- Good Thermal Conductivity
- Good Processability and Cost-effectiveness
To meet these requirements, CNC tools are typically made of the following materials:
- High-Speed Steel, such as the WMOAL series.
- Carbide, such as YG3.
- New Material Hard Metal Alloy, such as YG6A.
- Coated Tools, such as TiC, TiN, Al2O3, etc.
- Ceramic Tools: Can withstand high cutting speeds even at high temperatures.
- Superhard Tool Materials.