CNC milling machines offer high precision and repeatability, making them perfect for custom metal milling applications. To ensure the best results from your milling machine, it is important to know How To Control The Precision Of CNC Milling Machining. In this blog post, we will discuss some tips on how to achieve precise CNC milling results.
One of the most important factors in achieving precise CNC milling results is the quality of the cutting tools used. It is essential to use high-quality carbide or diamond-tipped cutting tools when performing CNC milling operations. The cutting tools should be sharp and have a good finish to minimize vibration and chatter during the machining process.
Another factor to consider when trying to achieve precise CNC milling results is the rigidity of the milling machine. The machine should be properly secured to a solid foundation to minimize vibration during operation. By following these tips, you can achieve precise CNC milling results for your custom metal parts.
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Accuracy Of CNC Milling: 3 Measurements

Position Accuracy
Position accuracy is a measure of how close a toolpath comes to the ideal or theoretical position. In CNC machining, position accuracy is determined by the machine tool, controller, program, and setup. The machine tool’s ability to maintain dimensional accuracy is critical in achieving the desired results from the CNC program.
The controller plays an important role in maintaining positional accuracy by interpolating the motion of the machine tool axes and providing feedback to the operator. The program used to generate the toolpaths also affects position accuracy. Finally, proper fixturing and setup are essential for ensuring that the workpiece is positioned correctly in relation to the cutting tools.
The position accuracy of CNC milling machines is typically within 0.0001 inches (0.00254 mm). However, this accuracy can vary depending on the type of machine, the type of material being machined, and the operating conditions.
For example, the position accuracy of a horizontal CNC milling machine (HMC) is typically within 0.0002 inches (0.00508 mm), floor-mounted CNC milling machines are typically more accurate than table-top models.
The position accuracy of CNC milling machines can also vary depending on the type of material being machined. For example, softer materials such as aluminum are easier to machine than harder materials such as stainless steel.
Repeatable Accuracy
The repeatable accuracy of a CNC milling machine is the degree to which the machine can produce the same results when making multiple identical parts. This is important because it determines how precisely the machine can manufacture parts.
The higher the repeatable accuracy, the more precise the machine will be. There are many factors that contribute to the repeatable accuracy of a CNC milling machine, including:
- The quality of the components used in the machine
- The manufacturing tolerances of the components
- The alignment of the components
- The rigidity of the construction
- The stability of the spindle
- The vibration damping properties of the materials used in construction
There are several ways to test and quantify the repeatable accuracy of a CNC milling machine. The most common method is to use a laser interferometer. This device measures the distance between two points with extreme precision and can be used to determine the accuracy of a CNC machine.
Once the measurements are taken, they can be compared to the dimensions of the part that was machined to see how accurate the machine was.
Another method of testing repeatable accuracy is to use a coordinate measuring machine (CMM). This device uses sensors to measure the position of points in space. It can be used to take measurements of parts that have been machined by a CNC machine to see how accurate the machine was.
Finished Product Tolerance
The Finished Product Tolerance of CNC milling is the allowable deviation from the specified dimensions of the finished product. This tolerance is determined by the manufacturing process, equipment capabilities, and materials used. The FPT is necessary to ensure that the finished product meets the required specifications and can be used for its intended purpose.
There are three main factors that affect the FPT of CNC milling: 1) the manufacturing process; 2) the equipment capabilities; and 3) the materials used.
1) The Manufacturing Process
The FPT of CNC milling is affected by the manufacturing process used. The type of milling machine,cutting tools, and fixtures all play a role in determining the finished product tolerance.
2) Equipment Capabilities
The FPT of CNC milling is also affected by the capabilities of the equipment used. The accuracy and repeatability of the milling machine, as well as the quality of the cutting tools and fixtures, will all impact the finished product tolerance.
3) Materials Used
Finally, the materials used in the manufacturing process will also affect the FPT of CNC milling. Different materials have different tolerances for machining, so it is important to select the appropriate material for the application.
How To Control

The precision of CNC milling machining can be controlled through a number of methods. The most important thing to remember is that the greater the degree of control, the more precise the final product will be. There are three main ways to control the precision of CNC milling:
1) Adjust the cutting speed. The faster the cutting speed, the less time the tool has to remove material, and thus the more accurate the cut will be. However, too high of a cutting speed can cause the tool to break or chip.
2) Use a smaller cutter. A smaller cutter will remove less material per revolution and produce a more accurate cut. However, using a smaller cutter can also increase wear on the tool and reduce its lifespan.
3) Use a higher quality cutter. A high quality cutter is made of harder material and will stay sharp longer, producing a more accurate cut. However, these types of cutters are more expensive.
4) Use a coolant. A coolant helps to keep the cutting tool from overheating and breaking. It also washes away chips and debris, keeping the cutting area clean and clear for better accuracy.
5) Repeat the process. If possible, run the same job through the machine multiple times to ensure accuracy. This is especially important for large jobs or jobs with tight tolerances. By following these tips, you can improve the precision of your CNC milling machine and produce better quality products.
If you find any problem in the CNC milling machine then you should contact Industrial Control Care. Industrial Control Care is a leading provider of industrial control system repair and maintenance services, offering 24/7 emergency support for all make and models of CNC milling machines. Industrial Control Care has certified technicians with years of experience providing quick, reliable and cost-effective solutions to any CNC milling machine problem.