Fastener Redesign During New Product Introduction

Field Redesign Yields 20 Times Longer Tool Life and Improved Quality

Challenge

While still in the product design stage, a Field customer requested a piece price quote for a high-cost fastener that was slated for inclusion in a new hand tool. The proprietary fastener was supposed to be resistant to vibration loosening, but prior to providing a quote, Field asked to review the design with purchasing and engineering teams.

During the initial build, the customer’s engineers found that the original fastener would consistently loosen. The proposed fastener featured a proprietary thread design that relied on the principle of thread interference, accomplished by the addition of a wave in the thread. Through testing, it was established that this design caused excessive installation torque and did not provide the desired results of resisting vibratory loosening in the application.

Not to mention, it was very expensive.

Solution

Field proposed an alternate fastener that came with a pre-applied microencapsulated patch. This patch releases beads during installation, causing the two-part epoxy to mix and create a bond line between the threads of the screw and the nut member. Field performed testing to validate the design and presented these findings to their customer's team of R&D engineers.

Results

The customer implemented Field's proposed design and, through internal testing, found the new design increased the life of the motor mount joint by 20 times and cut down on warranty claims! It also decreased the required installation torque while increasing the failure torque in comparison to the previous design.

A great example of how involving Field early on in the design phase will reduce total cost and improve quality!