Knowledge Hub
02/02/2025
Sub-Contract CMM Inspection
What is Sub-Contract CMM Inspection?
CMM inspection is a process used in manufacturing and quality control to measure the geometric characteristics of a product or component using a CMM machine.
Sub-contract CMM inspection refers to the outsourcing of coordinate measuring machine (CMM) inspection services to a third-party vendor or provider.
This involves sending parts or components to a subcontractor who has the necessary equipment, expertise, and resources to conduct accurate and precise CMM inspections.

By subcontracting this service, companies can ensure accurate and reliable measurement data without the need to invest in CMM equipment or dedicate internal resources to perform the inspections.
These services are essential for ensuring that products meet customer requirements and regulatory standards.
Types of Sub-Contract CMM Inspection Services
Sub-contract CMM inspection services may include the following:
Dimensional measurement services: These services involve using a CMM Machine to accurately measure the dimensions of a part or component. This can include measuring distances, angles, diameters, and other geometric features.
Geometric dimensioning and tolerancing (GD&T) inspection: This involves evaluating the form, orientation, and position of features on a part according to a set of standardised symbols and rules known as GD&T. CMMs are often used to perform GD&T inspections due to their high level of accuracy.
Part validation and verification: This involves using CMMs to verify that a part or component meets the required specifications and tolerances. This can include comparing the measured dimensions of a part to its CAD model or blueprint to ensure that it is within acceptable limits.
Reverse engineering: In this process, CMMs are used to create a digital model of an existing part or component by capturing its dimensions and geometry. This can be useful for reproducing or modifying existing parts without access to the original design data.

First article inspection (FAI): This involves verifying that the first production run of a part meets the specified requirements before full-scale production begins. CMMs can be used to perform detailed inspections of first articles to ensure their compliance with design specifications.
Statistical process control (SPC) analysis: This involves monitoring and analysing process data to ensure that manufacturing processes are in control and producing parts within specified tolerances. CMMs can be used to collect dimensional data for SPC analysis and to identify trends or patterns that may indicate potential quality issues.
How to Choose the Right Sub-Contract CMM Inspection Service
Before choosing a sub-contract CMM inspection provider, you should consider the following:
Experience and expertise: Look for a sub-contract CMM inspection service that has a proven track record of delivering quality services. Check if they have experience in your industry and if they have the necessary expertise to meet your specific inspection requirements.
Equipment and technology: Make sure the sub-contract CMM inspection service utilises state-of-the-art equipment and technology to ensure accurate and reliable results.
Quality assurance processes: It is important to choose a sub-contract CMM inspection service that has robust quality assurance processes in place. This will help to ensure that the inspection results are consistent, accurate, and reliable.
Turnaround time: Consider the turnaround time offered by the sub-contract CMM inspection service. Look for a service that can provide quick and efficient inspection services without compromising on quality.
Cost: Compare the pricing of different sub-contract CMM inspection services to find one that offers good value for money. Remember to consider the overall cost, including any additional fees or charges.
Reputation and references: Research the reputation of the sub-contract CMM inspection service by reading reviews and testimonials from past clients. Ask for references and contact them to get feedback on their experience with the service.
Location and communication: Consider the location of the sub-contract CMM inspection service and how easy it is to communicate with them. Choose a service that is easily accessible and responsive to your needs.
Compliance and certifications: Ensure that the sub-contract CMM inspection service adheres to industry standards and has the necessary certifications and accreditations. This will give you confidence in their ability to meet your inspection requirements.
What are the Benefits of Sub-Contract CMM Inspection?
Sub-contract CMM inspection has several main benefits to companies. These include:
Cost savings: Sub-contract CMM inspection can save money as you do not have to invest in expensive equipment, software, and training.
Expertise: By hiring a specialised CMM inspection service, you can benefit from their expertise and experience in accurate and efficient measurement techniques.

Quality assurance: Sub-contract CMM inspection ensures that your parts and products meet industry standards and quality requirements.
Time-saving: Outsourcing CMM inspection allows you to focus on other core activities of your business, saving time and resources.
Flexibility: Sub-contract CMM inspection allows you to scale up or down your inspection needs based on demand, without having to invest in additional resources.
Continuity: By partnering with a reliable CMM inspection service provider, you can ensure consistency and reliability in your inspection processes.
Which Industries Might Use Sub-Contract CMM Inspection Services?
Let’s take a look at the type of services which may benefit from sub-contract CMM inspection:
Automotive: Sub-contract CMM inspection services are essential for ensuring the quality and precision of automotive parts and components.
Aerospace: The aerospace industry relies heavily on CMM inspection services to ensure the safety and reliability of aircraft components and structures.
Medical Devices: The medical device industry requires strict quality control measures, making CMM inspection services crucial for ensuring the precision of medical devices.
Electronics: The electronics industry benefits from sub-contract CMM inspection services to ensure the functionality of electronic components and products.
Defence and Military: The defence and military sectors rely on CMM inspection services to ensure the reliability of weapons, equipment, and vehicles.

Precision Engineering: Industries such as tooling, moulding, and machining rely on CMM inspection services to maintain high levels of precision and accuracy in their products.
Energy and Power: The energy and power industry uses CMM inspection services to ensure the quality of components used in turbines, generators, and other power equipment.
Construction: The construction industry benefits from sub-contract CMM inspection services to ensure the accuracy of building materials and structures.