Ensuring Accuracy with Measuring Tapes: A Case Study

The accuracy of measuring tapes is crucial in various industries. A prominent case involving a truck door panel manufacturer highlights the critical role of measuring tape accuracy and the importance of relying on certified measuring tools.

In this article, we will explore a real-life scenario where a manufacturing company encountered significant measurement discrepancies. We will delve into the measures taken to identify and resolve the issue, emphasizing the importance of using accurate and certified measuring tools.

The Problem

One day, I received a call from a company that supplied door panels for trucks. The automobile manufacturer who purchased their products was experiencing fit issues, as the door panels did not all match in size. The company used tape measures to inspect all the dimensions of the panels leaving the production plant, but the size discrepancies persisted. This led to the hiring of a professional to investigate the cause of the problem.

The Investigation

To address the issue, a standard tape measure was created using a set of gauge blocks, which were accurate to a tiny fraction of an inch. These gauge blocks were combined to measure up to 4 feet in length. By comparing the factory's tape measures to this standard, we discovered significant discrepancies. The tape measures varied by up to a quarter of an inch, with the errors appearing in a cyclical pattern, being correct at some points and incorrect at others.

Root Cause Analysis

Further investigation and discussions with the tape measure manufacturer revealed the cause of the error. The scale on the tape measures was printed using a rubber roller that had become deformed. This deformation led to the printing of the scale in an incorrect manner. The error was subtle and would not have been detectable through a visual inspection alone.

Resolution and Lessons Learnt

To resolve the issue, all new Starrett tape measures were purchased for the customer, ensuring consistent and accurate measurements. A significant investment of over $100 per tape was made, but the cost was justified by the need for precision in the manufacturing process. In contrast, the cheaper tapes, which cost only $10 each, could pose a severe risk to the company's business if used exclusively due to their potential for error.

The company quickly realized the importance of using certified, accurate measuring tools and resolved to purchase only Starrett tapes in the future. Moreover, they developed a standard measure to regularly test new tape measures against, ensuring ongoing accuracy.

Conclusion

This case study underscores the critical importance of using accurate and reliable measuring tools in manufacturing and assembly processes. Investing in certified tools such as Starrett tapes may seem expensive, but the long-term benefits, including quality assurance and customer satisfaction, are invaluable. Always consider the potential consequences of using less accurate tools, as the implications can be significant and even devastating.