What is an end mill?
It is defined as a shank type milling cutter that has a cutting edge on the outer surface and cross-section. An end mill is a tool that rotates and shaves the sides and top surface of a processed item with an outer blade and a bottom blade of a cross-section, respectively. End mills are especially used in precision processing of electrical, electronic and automotive parts and molds.
Selection of end mill
The performance of an end mill varies depending on the settings such as the number of blades, twist angle, inclination angle, relief angle and coating type, and a suitable shape is required for high-speed cutting operations.
The main part details of End mills
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Product shape depending on the number of blades
The performance of an end mill varies depending on the settings such as the number of blades, twist angle, inclination angle, relief angle and coating type, and a suitable shape is required for high-speed cutting operations.
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Issues and solutions when using an end mill
| Damaged blades |
- Fast transfer speed, excessive amount of slotting
- Excessive protrusion of tool
- Inadequate stiffness of tool
- poor fixation of item
- Poor fixation of item
|
- Reduce transfer speed
- Reduce amount of slotting
- Reduce amount of protrusion
- Use minimum blade length
- Increase fixed stiffness
- Increase fixed stiffness
|
| Vibration occurred during cutting |
- Excessive primary outer relief angle
- Excessive protrusion of tool
- Improper cutting conditions
|
- Reduce primary outer relief angle
- Reduce the amount of protrusion
- Adjust cutting and transfer speeds
|
| Reduced cutting performance |
- Use unsuitable end mill
- Low outer inclination angle
- Rapid wear of cutting blades
|
- Use an end mill suitable for items to be cut
- Increase outer inclination angle
- Perform early regrind
|
| Sudden occurrence of wear |
- Excessive cutting speed
- Unsuitable outer inclination angle
- Upward cutting operation
|
- Reduce cutting speed, modify outer inclination angle
- Consider downward cutting operation
|
| Poor chip discharge |
- Small space for chip discharge
- Excessive wear on blades
- Excessive amount of slotting
- Low injection pressure or amount of cutting oil
|
- Reduce transfer speed and use an end mill with small number of blades
- Perform early regrind
- Reduce amount of slotting
- Increase injection pressure and amount
|
| Poor surface roughness |
- Fast transfer speed
- Rapid wear of cutting blades
- Excessive amount of slotting
- Low cutting speed
|
- Reduce transfer speed
- Perform early regrind
- Reduce amount of slotting
- Increase cutting speed
|
| Damaged during cutting |
- Fast transfer speed
- Excessive protrusion of tool
- Significant damage of cutting blades
- Excessive amount of slotting
|
- Reduce transfer speed
- Reduce amount of protrusion
- Perform early regrind
- Reduce amount of slotting
|
| Poor processed dimensions |
- Small number of blades
- Excessive cutting conditions
- Use of long blades
- Poor accuracy of machine or chuck
|
- Use an end mill with a greater number of blades
- Adjust cutting conditions, replace
- Use short blades, repair or replace machine or chuck
|
