As a CNC machine operator, you are certainly aware of how important precise milling, precise metal processing, speed, and accuracy of processing are. If you want to produce the highest quality parts and products, all aspects of the processing process must be performed with great precision. This is a multi-stage operation. It starts from programming machines to the actual processing of parts, and each step must be performed professionally to achieve the desired results. Any inaccuracy can result in a defective product, which affects the manufacturer's reputation and also threatens the safety of consumers. CNC milling is becoming increasingly popular as it automates the process of metal and plastic processing. This article discusses the importance of precision and accuracy during processing using CNC. Check out the factors worth improving to perfect your products and milling!
Precise CNC milling - how to improve it?
Similar to other CNC machining processes, CNC milling itself relies on a computer to control the movement of the tool. The level of precision and accuracy of CNC machining is controlled by the settings of the computer program that directs the movement of the tool.
Several factors can influence the accuracy and precision of CNC milling and the best metal processing. For example, it can be the type of material being machined, the condition of the blades, the accuracy of the machine tool. To achieve the best results, it is necessary to understand these factors and take steps to minimize their negative impact or improve quality. Pay attention to the following points to improve the accuracy and precision of CNC milling:
- Use high-quality tools - While the tool movement during CNC milling is automated, high-quality tools also add value during machining. Make sure you are using a tool designed for a specific type of cut. You should also regularly calibrate your machine tools to ensure their highest precision.
- Learn about the properties of materials – During processing, it is necessary to consider the properties of the material, such as tensile strength, yield point, or thermal expansibility of the object being processed. Remember that a material with low plasticity deforms more than a material with high plasticity when subjected to the same shearing force.
- Update software and machine build – Currently, machine manufacturers CNC (computer numerical control) are adding new features and regularly updating software to increase productivity. Users can quickly update them to optimize the value of their investment. Moreover, at present, one of the fastest ways to increase the speed and accuracy of CNC machining is to upgrade to a five-axis machine. If you have a three-axis machine, you may be losing time on additional settings during production. However, when your machine operates on multiple axes, you save time on faster part retrieval. You also don't have to worry about errors made during multiple configurations. Automatically controlled devices and modern machines operate with high accuracy during serial production as long as they are regularly updated.
- Take care of cutting tools - Improving cutting tools means using tools specially designed for the type of material being processed. These can be metals and plastics. There are various types of cutting tools to choose from, so select the one that best fits the specific product and shaped surfaces.
- Monitor tool wear – Tool wear is caused by the contact between the tool and the workpiece. During operation, the size of the tip decreases and the shape of the tool's cutting edge changes. This can result in inaccurate cuts and the production of low-quality parts. Remember that if your tools are in excellent condition, they will work longer and better. Dull, worn tools require frequent replacement, which can take some time. There are several ways to reduce CNC machining tool wear and avoid unexpected breakdowns. When it comes to unplanned downtime, equipment failure is the cause of about 40 percent of problems. Moreover, such a failure statistically costs 10 times more than planned maintenance. In such a case, it is worth using predictive maintenance. Unlike regular maintenance (also known as preventive maintenance), predictive maintenance uses data to determine the best time to perform maintenance tasks, regardless of the state of the equipment. Predicting when maintenance tasks will be performed on CNC machining equipment reduces unnecessary maintenance and prevents unplanned downtime caused by machine failure.
- Analyze the material - The material being processed greatly affects the precision and accuracy of the finished product. Hard materials, such as steel, can be processed with greater precision and accuracy as opposed to softer materials, such as aluminum or plastic products.
- Take care of the CNC machine – The condition of the CNC machine also affects the precision and accuracy of the finished product. If the machine is not properly calibrated or worn out, the finished product will be made in a faulty and imprecise manner.
- Use setters - When preparing your machine for work, use preset tool settings to make your work more precise. These new additions measure the accuracy of tool placement within a minute. For comparison, an operator needs over an hour to set 15 tools for a given project using a probe. Using setters also increases accuracy, as the system can determine the exact position of the mill, allowing for more precise cutting. Thanks to more accurate tool positioning, your work is not burdened with errors that occur during manual equipment setup.
- Staff and CAM - Machining can be improved in many ways. First, analyze the work of your employees. If employees lack organization in machine operation, they may waste time or make mistakes. If you update your CAM software, make sure all employees are fully trained in its use. Another way to modernize equipment for greater precision is to change the motion control system. The accuracy of the control system depends on how much it mitigates tilt, inclination, and deviation - movements around the X, Y, and Z axes.
Why is accuracy and precision important in CNC?
While the accuracy of machined parts is crucial in every industry, in practice some sectors require perfect accuracy. These include:
- Medical sector - Devices used in medical procedures, such as robotic arms for laser surgery, rely on precisely machined micro and macro parts.
- Aviation industry - Aviation components must meet the strictest tolerances to ensure safe operation of the aircraft in any environment.
- Transportation - Buses, trucks, trains, and other vehicles require seamless cooperation of various shafts, clutches, pistons, and other parts.
- Energy industry - Whether it's natural gas and oil, wind energy or other sources, industrial equipment used for energy production and management requires precisely machined parts that can withstand immense pressure.
These are just a few examples of industries that require extraordinary precision in the production of machined parts. The repeatability of precision parts is crucial for everything from consumer products to spare parts. Let's also remember that the accuracy of CNC milling is also very important for the mechanical workshop itself. Maintaining accuracy reduces production time and costs, as well as eliminates the need to redo erroneous production projects.