The method of reducing the radial runout of CNC milling tools is so practical!

There are many reasons for machining errors in CNC milling machine cutting. The error caused by tool radial runout is one of the important factors. It directly affects the small shape error that the machine tool can achieve under ideal machining conditions and the geometric shape accuracy of the machined surface. The following introduces how to reduce the radial runout of CNC milling machine tools.

1. Use sharp tools

Use a larger tool rake angle to make the tool sharper to reduce cutting force and vibration. Use a larger tool back angle to reduce the friction between the main back face of the tool and the elastic recovery layer of the transition surface of the workpiece, thereby reducing vibration. However, the rake angle and back angle of the tool cannot be selected too large, otherwise it will lead to insufficient strength and heat dissipation area of the tool. Therefore, different tool rake angles and back angles should be selected according to specific conditions. Smaller ones can be used for rough machining, but larger ones should be used for fine machining to reduce the radial runout of the tool, making the tool sharper.

2. The front face of the tool should be smooth

When using the CNC milling machining center, a smooth front face can reduce the friction of the chips on the tool, and can also reduce the cutting force on the tool, thereby reducing the radial runout of the tool.

3. The amount of cutting should be selected reasonably

If the cutting amount is too small, the processing will slip, which will cause the radial runout of the tool to change continuously during processing, making the processed surface rough. When the cutting amount is too large, the cutting force will increase accordingly, resulting in large deformation of the tool, increasing the radial runout of the tool during processing, and also making the processed surface rough.

4. Cleaning the spindle taper and chuck

The spindle taper and chuck of the CNC milling machining center should be clean, and there should be no dust and debris generated during the processing of the workpiece. When selecting a processing tool, try to use a tool with a shorter extension length. When cutting, the force should be reasonable and uniform, not too large or too small. When learning UG programming, you can add the teacher's WeChat 'SGLS93

5. Use reverse milling during finishing

During forward milling, the gap position between the lead screw and the nut is changing, which will cause uneven feeding of the worktable, resulting in impact and vibration, affecting the life of the machine tool, the tool and the surface roughness of the workpiece. When using reverse milling, the cutting thickness changes from small to large, and the tool load also changes from small to large, and the tool is more stable during processing. Note that this is only used during finishing. Down milling should still be used during roughing, because down milling has high productivity and the service life of the tool can be guaranteed.

6. Reasonable use of cutting fluid

Reasonable use of CNC milling center cutting fluid. Aqueous solution with cooling as the main function has little effect on cutting force. Cutting oil with lubrication as the main function can significantly reduce cutting force. Due to its lubrication function, it can reduce the friction between the front face of the tool and the chip and between the back face and the transition surface of the workpiece, thereby reducing the radial runout of the tool.

7. Use strong tools

The strength of the tool can be increased in two main ways. First, the diameter of the tool bar can be increased. Under the same radial cutting force, the tool bar diameter increases by 20%, and the radial runout of the tool can be reduced by 50%. Second, the extension length of the tool can be reduced. The greater the extension length of the tool, the greater the deformation of the tool during processing. The tool is in constant change during processing, and the radial runout of the tool will change continuously, resulting in an uneven surface of the workpiece. Similarly, if the extension length of the tool is reduced by 20%, the radial runout of the tool will also be reduced by 50%.

Practice has proved that as long as the degree of manufacturing and assembly of each part of the machine tool is guaranteed, and reasonable processes and tooling are selected, the impact of the radial runout of the tool on the processing accuracy of the workpiece can be greatly reduced.