Posted December 17, 2020

The Importance of First Article Inspection in Manufacturing

Turner miller verifies the accuracy of manufacturing steel parts with a caliper

First article inspection (FAI), a process shared across nearly every type of manufacturing industry in the world, allows suppliers to formally report measurements of the initial part manufactured in cooperation with a customer who reviews and approves it. Customers expect verification of a project’s specifications, and manufacturer's need to document their work to set the standard for production runs.

For a machine shop, first article inspection ensures that the first part manufactured is built exactly to the dimensions specified in the original design data and documented as the standard for future production of the same part. This article will define the purpose of first article inspections in manufacturing, and how it’s important to the parts in your next project.

The Purpose of a First Article Inspection in Manufacturing

Before a part goes into production at a CNC machine shop, it goes through an engineering review. Once a design is deemed manufacturable, and the necessary materials are received, the first article of the part is fabricated. Upon completion, the part will go through the first article inspection, designed to accomplish the following:

  • Verify: Initially, the manufacturer verifies that the first part created matches the specifications supplied by the customer. Machine shops work with electronic data for the machine tools and drawing documentation that specifies the size, shape, and dimensions of the product. Quality inspections and FAI inspections are performed against a customer-supplied, 2-dimensional print of the part design, that often contains extra information about tolerances for specific features of the part. 
  • Document: The inspection of the first article will be documented for two reasons. First, to ensure that the production runs of the part match the first article, the manufacturer will rely on the first article inspection report for periodic audits to verify conformance. Second, parts that are built for certain industries, such as aerospace, must have their first article inspections documented in conformance to set standards.
  • Confirm: The first article inspection verifies that the part matches the initial specifications, and opens up additional communications with the customer. For instance, the machine shop will use a first article inspection report to confirm the design specifications of the part or alter those specifications as needed. In these situations, the FAI surpasses a simple pass or fail report, becoming an instrument for refining the specifications to best fit the customer’s needs.

Next, let’s look at the actual inspection process itself.

The Inspection Process at a Parts Manufacturer

Machine shops have rigorous quality control procedures in place to monitor the production of the products they build, all under the oversight of the manufacturer’s quality control team. A member of the Quality team typically performs the FAI of a new part. While each machine shop will have its variation of the FAI process, it results in a report with plus or minuses on dimensional callouts to identify any deviations found in the measurements.

A state-of-the-art coordinate measuring machine collects the data necessary for a first article inspection. These systems have a solid base, or table, usually made of granite that has been ground flat for stability. The part is positioned on the table and measured by contact or non-contact probes, or a combination of both. Contact probes are made from ruby or other rigid materials that won’t change size with temperature fluctuations. They come in different sizes to accommodate different shapes. Non-contact probes on the other hand use laser or optical sensors to take their measurements. The probes are attached to a gantry or bridge that moves around the part and can move independently to follow any unique contours on the part being measured.

Once completed, the FAI report presents the data collected from the coordinate measuring back to the customer.

How Your Machine Shop Will Use the First Article Inspection on Your Projects

FAI reports document that the design specifications of your part are understood, verified and accounted for, but it’s more than a simple report. When the Quality team uncovers deviations from the design specifications, it allows the machine shop to resolve the root causes of the problem. The machine shop and the customer work together on how to enhance and improve the design in order. Lastly, it will satisfy the need for industry standards in documentation such as AS9100, the standard for quality management systems in the aerospace industry.

At Plethora we offer first article inspections to our customers to satisfy your need for manufacturing validation of the parts that we build for you. Not only will the FAI be following AS9102 specifications if required, but we also offer certificates of conformance. We’re available to answer your questions on how an FAI will help with your project, as well as our commitment to quality. We look forward to partnering with you on your next project! To get started, please upload your design files to Quote My Part or call us at 415-726-2256.

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The Plethora Team

The Plethora team is your go-to CNC manufacturer for hardware done right the first time. We have the tools and experience needed to create high quality custom parts quickly and with precision, whether you need a prototype or production run.

Topics: Manufacturing