What is the best method for verifying CNC machine tool accuracy?

by Hannah Brown on Dec 17, 2025 10:27:28 AM

In 5-axis CNC machining, accuracy is essential. Manufacturers are working to tight tolerances, machining the most high-value and complex of parts. Without proper CNC machine accuracy checks in place, there is a risk of costly mistakes causing scrap, rework and missed deadlines. Machine tool accuracy can be affected by wear and tear, environmental factors, poor setup, operator error or machine tool crashes.

Verifying CNC machine tool accuracy is vital to protect parts, increase quality and keep production running smoothly. In this article, we explore the best method for CNC machine tool verification in terms of accuracy and efficiency.

What methods exist?

There are many options within the industry such as dial indicators, ballbars and laser systems to verify the accuracy of a machine tool. Whilst these options provide a solution to test or ensure the accuracy of a machine tool, they share a variety of drawbacks:

Human Input: These devices all require manual processes for use, introducing the potential for error and variability.
Skilled Workers: Skilled personnel are usually required to achieve the correct level of accuracy.
Limited: This type of equipment often has to be used in conjunction with other tools to provide a full picture of the accuracy of the machine tool. Even then they can be limited to assess full 5-axis machine performance.
Time-consuming: To get the required accuracy, processes can take hours to complete and often the machine tool needs to be taken out of production during this time.

In the current manufacturing climate, these limitations are costly.

Assessing machine tool accuracy needs to be part of a shopfloor strategy and NC-Checker is the best tool to verify the CNC is accurate and capable of machining parts to tolerance.

The Smarter Approach: MSP’s NC-Checker

As an alternative, CNC metrology software, NC-Checker, is the quickest, accurate and most effective way of verifying CNC machine tool accuracy. The metrology software performs various tests, including rotary and linear axis checks, to confirm whether the probe and machine are within tolerance. On completion of the tests, the software produces ‘Benchmarks’ which demonstrate, at-a-glance, if any errors are present and where these errors lie so they can be resolved before machining begins.

This makes it a smart manufacturing power to be reckoned with because of the reasons below.

Automatic
Unlike manual processes, NC-Checker works at the press of a button. There is no need for the machine to be taken out of production and no input from the operator has the potential to affect results.

Fast
NC-Checker can take around 20 minutes to complete its machine-checking cycle, making it possible to introduce the software as a standard operating procedure if needed.

Comprehensive Analysis
NC-Checker assesses the full geometric performance of the machine to ensure it is capable of machining parts to tolerance. It highlights if errors on the machine are kinematic or mechanical so exact problems can be pinpointed. Furthermore, the software will automatically rectify the kinematic errors, making it more than just a verification tool.

Shopfloor Consistency
NC-Checker allows manufacturers to compare performance across multiple machines to help with resource allocation or understand part-to-part variation across the shopfloor. Furthermore, the software can show the effect environmental changes may be having across the shopfloor or throughout the day.

Performance Monitoring
NC-Checker’s benchmark allows machine tool performance to be tracked over time to anticipate machine failure and book maintenance for a convenient time.

Clear reporting
The CNC metrology software produces ‘Benchmark’ reports each time it is run for clear analysis and traceable archives to make quality assurance straightforward.

An added bonus

NC-Checker uses 5-axis probing to analyse the machine tool and verify its accuracy. It is therefore imperative the CNC probe is set up correctly and accurately calibrated to ensure no errors influence NC-Checker’s results.

This is where MSP’s AutoClock comes in. The metrology device ensures the probe is accurately setup and calibrated without human input to remove any error from this stage in the process. It also uses a 5-axis calibration, ensuring the probe’s results are valid in any tool orientation and ruby contact. NC-Checker automatically runs after this and manufacturers can be safe in the knowledge the probe setup or calibration has no chance of affecting results. Without AutoClock, using probing for machine or part setup cannot be trusted and the results may not always be valid.

Assessing machine tool accuracy needs to be part of a manufacturer’s shopfloor strategy and NC-Checker is the best tool to verify the CNC is accurate and capable of machining parts to tolerance. Without machine performance analysis or monitoring being included in a probing solution, it is impossible to know whether part probing results are valid or accurate.

For manufacturers committed to quality and efficiency, it is a manufacturing must.