In the process of CNC machining of plastic parts, burr problem has always been a challenge faced by many manufacturers. Are you also troubled by this problem? Today, I will explore this issue in depth, analyze the causes of burrs, and share some practical solutions to make your CNC machining process smoother. As CNC machining experts of VMT, we continue to explore and practice these methods to help customers improve production efficiency and ensure that each part achieves the best machining effect.
What is burr in CNC machining of plastic parts?

In the process of CNC machining, burr refers to the tiny irregular protrusions on the surface or edge of the material when the part is cut, engraved or drilled. Especially in the processing of plastic materials, burrs are more common and more difficult to remove. They not only affect the appearance quality of the parts, but may even affect the performance and function of the parts. Therefore, for CNC machining of plastic parts, how to effectively solve the burr problem is crucial.

The formation of burrs in CNC machining is not accidental. It is usually the result of the combined action of multiple factors. The following are common causes of burrs:

1. Tool problem

Tool wear or improper selection is a major cause of burrs in plastic parts. When the tool is not sharp and the cutting is not smooth, more burrs are likely to be generated.
2. Too fast processing speed

In CNC processing, too fast feed speed or cutting speed will cause the material to be forcibly cut, resulting in burrs. In particular, plastic materials are relatively soft. When the tool cannot cut smoothly, it is easy to cause the edge of the plastic to tear and form burrs.
3. Material properties

Different types of plastic materials will show different processing characteristics during CNC processing. For example, some plastics (such as polypropylene or nylon) are more likely to form burrs than other plastics because their cutting characteristics are more complex and they are prone to cutting residues.
4. Improper cutting process design

If the cutting strategy used in the processing process is improper, the tool does not fully cut into the material, or the path design is unreasonable, it is easy to cause burrs.

Problems that burrs may cause

Although burrs seem to be just surface flaws, they may bring a series of potential problems that seriously affect production and product quality.
1. Appearance problems

Burrs affect the appearance of plastic parts and leave a bad impression on customers. Especially for products that require high precision and high appearance quality (such as consumer electronic housings, medical equipment, etc.), the presence of burrs is particularly inappropriate.
2. Impact on assembly and use

If the burrs are not removed in time, they may affect the fit between parts and cause assembly difficulties. For precision assembled products, burrs may even cause parts to get stuck or damaged.
3. Material fatigue

In long-term use, burrs are prone to become stress concentration points, which may cause material fatigue, fracture and other problems, affecting the service life of parts.
4. Increased difficulty in subsequent processing

Burrs will increase the difficulty of subsequent processing, especially if post-processing such as cleaning and painting is required. Burrs may cause these steps to proceed unsmoothly and increase production costs.
How to effectively solve the burr problem in CNC processing of plastic parts?

In the face of burrs, we cannot be helpless. Here, I will share some effective methods in actual operation to help you reduce or remove burrs and improve the processing quality of parts.
1. Choose the right tool

The right tool selection is the key to avoiding burrs. We recommend choosing sharp tools, and the hardness of the tool material should match the hardness of the processing material. For plastic materials, using coated tools can reduce material adhesion during cutting and reduce burr generation.
2. Adjust cutting parameters

Reasonable cutting parameters are very important. Appropriately reducing the feed rate and cutting speed can avoid excessive cutting, reduce material tearing and burr generation. The cutting depth should not be too large, and appropriately reducing the cutting amount can effectively control the occurrence of burrs.
3. Accurately control the cooling system

Using coolant or gas for cooling can help plastic materials maintain a stable temperature during processing, avoid overheating and cause the material to melt, thereby reducing the generation of burrs.
4. Post-processing deburring

After processing is completed, post-processing is a common method to remove burrs. Post-processing can be performed by manual deburring, sandblasting, ultrasonic cleaning, etc. If it is a precision part, laser deburring technology can be used.
5. Optimize processing technology

For some parts with complex shapes, the generation of burrs can be reduced by changing the cutting path, adjusting the tool angle, etc. In addition, adding a fine cutting process can also effectively remove burrs.
Benefits of solving the burr problem

When we successfully solve the burr problem, the benefits are self-evident.
1. Improve appearance quality

After removing the burrs, the surface of the parts is smooth and flat, and the appearance is greatly improved, which can meet the needs of high-demand customers. This not only improves the corporate image, but also enhances customer satisfaction.
2. Improve the functionality of parts

Removing burrs can avoid assembly difficulties caused by burrs and ensure the matching accuracy of each part. This is especially important for precision equipment and effectively improves the performance of parts.
3. Extend service life

Removing burrs can reduce material fatigue and reduce the failure rate of products, thereby extending the service life of parts. This is especially important for parts that are used for a long time, which can save maintenance and replacement costs.
4. Reduce production costs

Although removing burrs requires a certain amount of post-processing time and cost, in the long run, this can reduce the rework rate and quality problems, thereby reducing overall production costs.
Related questions
H1: What are the benefits of using coolant in plastic CNC processing?

The role of coolant in plastic CNC machining is not only to cool the tool, but also to effectively reduce friction, extend tool life, and reduce burrs and burns. The correct use of coolant can significantly improve machining efficiency and quality, especially in high-precision machining.
H1: How to choose the right tool material for plastic CNC machining?

Choosing the right tool material is the key to improving CNC machining quality. For plastic materials, carbide tools or coated tools are usually used, which can provide better cutting performance, reduce burrs, and extend tool life.
H1: How to avoid excessive tool wear during plastic CNC machining?

An effective way to avoid excessive tool wear is to use low-speed cutting and appropriate cutting pressure. In addition, using appropriate tool coatings and regular tool replacement are also effective means to avoid excessive wear.

To solve the burr problem in CNC machining of plastic parts, comprehensive measures need to be taken in terms of tool selection, cutting parameters, cooling system and post-processing. By continuously optimizing the processing technology and equipment configuration to reduce the generation of burrs, not only can product quality be improved, but also production costs can be reduced. I hope today’s sharing can help you cope with these challenges in actual operations and ensure that every part can achieve the best processing effect.