Frequent problems and solutions in the processing of CNC machining centers

01The surface of the machined parts is not flat or smooth

In CNC milling machine parts processing, surface finishing is an important process, and it is also a frequently done process, which requires high surface quality. However, in actual processing, sometimes an uneven and uneven surface is obtained, which does not meet the requirements.

The main reason for this problem is that in the finishing process, the performance of the cutting oil cannot meet the processing requirements. When the tool feed speed is too fast, the vibration caused by the rapid movement of the tool will easily leave an uneven track on the machined surface. Sometimes the tool marks between two adjacent tool paths will have a certain difference, which is caused by the inconsistent cutting direction of the tool. To avoid this problem, you should use the full down milling method and use special cutting oil.

02The tool marks on the side of the finish milling are too obvious

In the machining of workpieces on CNC milling machines, almost every workpiece needs to be precisely milled. But in many cases, there will be too obvious tool marks on the side of the finish milling. This is not allowed and will seriously affect the appearance of the workpiece.

The main reason for this problem is improper selection of the position and parameter of the tool advancement and retreat. The milling methods provided by different processing software will be different, but the depth selection of the tool and the parameter selection of the tool will all be provided.

In addition, when using non-special cutting oil, due to insufficient pressure and anti-wear properties, the oil film breaks instantaneously during the processing, causing scratches on the workpiece. If you want to avoid the above improvement problems, you can make relevant adjustments from four aspects.

The first is to select the feed point correctly, the second is to add an overlap when cutting in the middle, the third is to use full-cut deep processing when finishing the side surface, and the fourth is to use special cutting oil.

03 Tool change marks during finishing milling

In ordinary machining and high-speed machining, the tool needs to be replaced. If you do not pay attention to the relevant adjustment of the parameters during the tool change operation, obvious traces will appear, which will seriously affect the appearance of the workpiece.

When finishing milling on the bottom or side, tool marks often appear. Many times people think this is an inevitable mistake. In fact, it is completely avoidable. In order to solve this problem, in the processing of the workpiece, the finishing of the concave corner needs to be replaced with a small tool. Due to the force and swing during the machining process, it is easy to produce tool marks at the corners.

04After polishing, the surface or side will leave burrs or sharp edges

Modern precision parts processing has higher and higher requirements on the surface, and burrs or cracks are unacceptable. If a file is used to correct the part, it will also affect the accuracy and size of the CNC part. Use directly after grinding without further grinding. But in actual production, there are still many burrs and sharp edges.

To solve this problem, you need to pay great attention to the use of tools and use special tools to ensure sharp cuts. In addition, it is necessary to plan the tool path and increase the secondary finishing tool path, that is, the surface is processed first, then the side surface, and then the surface is processed to ensure that there are no burrs and sharp edges, which is very useful for workpieces that cannot be polished.

05Finish machining of special-shaped and accurate parts

For the finishing of some special-shaped machined parts, the software usually has fitting errors. Sometimes if the calculation error is too large, it will cause deformation of the parts and affect the appearance. To solve this problem, you need to start with software and control errors. This value is reasonable, and neither affects the calculation speed nor deforms the workpiece.