What Is CMM Programming?

For businesses involved in mass production, a great deal of revenue generation will ride on the volume of production. And while that is a priority, it is not true that manufacturing companies value production output above everything else. 

Safety is always the primary concern in any manufacturing operation, with product quality trailing closely behind. Ensuring safety is a collaborative effort, but when it comes to maintaining and upholding quality, Coordinate Measuring Machines (CMMs) are absolutely critical.

What Is a CMM?

A CMM is a machine that creates models and prototypes from design drawings. It can also reverse-engineer a design by creating design drawings from prototypes.

CMMs have four main components: the body, the measuring probe, the control system and the measuring software. All of these components work together to enable the machine to perform its critical functions, such as highlighting errors and anomalies in the manufacturing process.

With the primary function of CMMs, manufacturers can identify potential bottlenecks in their operation, improve efficiency and boost product quality drastically, which can translate to higher productivity and profitability. 

What Is CMM Programming?

CMM programming is the process of setting up, calibrating and installing CMM programming software to be used by CMMs. In this regard, a CMM programmer’s role is critical as it handles all aspects of CMM programming. These include, but are not limited to, the following tasks:

  • Building of inspection software.
  • Testing of software to ensure machine functionality.
  • Collection of drawings, diagrams and prototype information.
  • Installation of automation software for faster inspections and data collection.
  • Setting up the software for the performance of specific tasks after data extraction, such as data reporting, object comparisons and software integration.

What Does a CMM Do?

Essentially, a CMM is a machine that is capable of obtaining accurate measurements of the geometrical characteristics of an object. A measuring probe, stable platform, and robust data collection software enable the machine to take measurements from any object or part. It then gathers the data and transmits it to a computer for analysis.

But the function of CMMs isn’t limited to this function. They are versatile pieces of machinery that can be used to perform a wide range of tasks. A CMM can confirm the accuracy of tests performed and measurements collected. For instance, it can test a factory machine and determine whether parts produced on the assembly line were built with the correct specifications by comparing them with original design drawings or the information supplied by CAD software.

Additionally, a CMM can perform tasks that would otherwise be too difficult or impossible to achieve by hand. This includes measuring and ascertaining the accuracy of a shape or the roundness of a hole.

When used with CAD software, CMMs can create 3D design models to improve quality control during the manufacturing process. Through the machine’s enhanced capabilities, manufacturers can modify their designs and tweak specifications as needed while shortening the time between each design iteration or revision.

What Is CMM Calibration?

CMM calibration is the process of testing and retesting the machine against a known standard to ensure the machine’s accuracy and precision. This critical process should be performed immediately after installing a new probe tip to ensure the reliability of measurements and data taken.

The process of calibration is done comprehensively before the machine can be used. This is achieved using a calibration sphere with known dimensions and geometric qualities. After mounting the sphere, the machine will print out the information it obtains on the surface while data is fed to the CMM programming software. 

The accuracy of the data it obtains will determine whether the probe is ready for use or needs further tweaking. 

What Does a CMM Operator Do?

While a metrology companies programmer deals with the setup and testing of CMMs, a CMM operator deals with all matters that deal with the operation of the machine. CMM operators are also called CMM technicians and are responsible for the following tasks:

  • Handles the controls of the measuring probe and uses the machine to take the required measurements while using a manual setup.
  • Responsible for initializing the automation software that will be used to measure the dimensions and specifications of the object to be inspected.
  • Uses the machine software to collect and utilize rich data provided by the machine and incorporate those measurements obtained in designing, quality control, or developing new processes or products.

How Do CMM Probes Work?

The probe is one of the main components of a CMM responsible for collecting data from an object or part being tested.

A CMM probe is directly mounted on the CMM and can be operated manually or automatically using pre-programmed automation software. Once the probe is operated, it will move around an object tested to take detailed measurements.

How Do CMMs Measure Flatness?

CMMs are versatile machinery capable of taking complex measurements that would otherwise be too difficult or impossible to handle manually. This includes the ‘flatness’ of an object.

The flatness of a surface is measured using the CMM stylus, which can be operated or programmed to take accurate measurements along an object’s surface. Using the stylus, the CMM can scan the entire object’s surface to detect how flat it is and compare the data it collects with others to generate a report on the object’s flatness.

CMMs follow different measuring subroutines to measure an object’s flatness. It uses such values as probe scanning speed and step increment width and their effects on flatness measurements to indicate an object’s surface quality and flatness accurately.

How Do Portable CMMs Work?

Most definitions of CMMs typically refer to traditional CMMs, also referred to as fixed CMMs. They offer high levels of precision and accuracy when taking measurements but offer one distinct disadvantage: lack of mobility. Objects will need to be brought to the machine whenever measurements need to be taken.

Portable CMMs offer the same benefits while eliminating some of their other disadvantages, such as the lack of mobility and the limitations on the weight and size of objects that can be measured. The machine can be brought to the object itself whenever a measurement needs to be taken.

With improved mobility and flexibility, users can make use of the machine’s full capabilities without requiring special environments. One tradeoff, however, is that they are typically less accurate than traditional CMMs.

How Accurate are CMM Machines?

CMMs are incredibly accurate machines, capable of taking incremental measurements that would be otherwise close to impossible to measure using any handheld device or tool. They are infinitely more accurate than other hand measurements and are capable of providing reliable, specific data that could be used to improve the efficiency of manufacturing processes.

Assembly lines are built on accuracy and precision. These aspects of production ensure that all products being manufactured on the line bear the exact specifications, which is the main point of mass production. Bearing all of these in mind, CMMs are integral in helping manufacturers maintain the quality of their products throughout all aspects of production.

However, it’s also important to remember that the machine’s accuracy depends on how well it’s calibrated and operated. CMM operators must receive appropriate training to handle the machine correctly and achieve the best results. Regular calibration is also important to ensure the accuracy and reliability of the measurements acquired.

How to Use a CMM

CMM programming typically determines how an automated CMM is operated and will depend on how a CMM programmer sets it up.

Meanwhile, a manual CMM is operated by moving the probe using a joystick or by hand to the object or part that needs inspection. Once it is moved, the machine will take all necessary measurements and transmit all acquired data to the computer.

Here is a more detailed, step-by-step guide on how to operate a manual CMM:

  1. Evaluate what measurements to take by referring to drawings of the object or a measurement plan.
  2. Install the appropriate probe, depending on the object to be measured. Calibrate the machine before operating it to ensure the reliability of results.
  3. Measure the reference elements by bringing the axis to the line.
  4. Make sure the object or part to be measured is perfectly aligned. Once done, assign a designated z-axis.
  5. Acquire the measurements needed.
  6. Use the CMM programming software to generate reports or compare the data with other datasets.

Which CMM Software Program Is Best?

ATT Metrology Solutions offers PC-DMIS and Metrolog X4 software with custom reporting available as part of our CMM inspections.  These software products are designed with the end-user in mind to bring out the machine’s full capabilities and come with an easy-to-understand interface that allows seamless integration of essential features such as data collection, analysis and reporting.

Whether you need to validate complex geometries or create automated inspection routines to take care of multi-batch inspections, ATT Metrology Solutions CMM services are available to meet your needs.  Call us at 888-320-7011 or contact us through our online form to learn more.

Learn more:

What is CAD Modeling?

What is Laser Metrology?