New Product Design--Why It's the Best Time to Evaluate Your Fastener Application
Fasteners can easily be overlooked in the design process. However, evaluating fasteners and their application during the Conceptual and R&D stages can make a profound impact in your project’s success. The figure outlines the cost impact of making changes throughout the production cycle. By including our engineering experts during the design and development phase, Würth can increase your ability to deliver a product at both the lowest cost and maximum quality.
Würth’s Engineering Expertise Can Assist In New Product Development
- Proper design and selection of fasteners can reduce product and assembly costs.
- Drive down the piece price costs of components by eliminating costly manual operations such as applying thread-locker or tapping.
- Würth’s Engineering team follows non-disclosure protocols and proprietary restrictions.
How a $0.04 Screw Can Cost You More Than $380,000
Würth Engineers Involved in NPD Can Prevent Costly Design Errors and Delayed Product Launch
A customer had redesigned a very large volume assembly. The previous design used a tapping screw to form its own threads into the plastic to hold the assembly together. This design does not allow a high degree of serviceability, as the plastic loses its
ability to hold the assembly together as the screw is removed and reinstalled several times. Therefore, it was decided to use a molded insert with a regular machine screw in its place. However, they did not know that a tapping screw is more than twice as strong as a machine screw/threaded insert assembly of the same diameter.
When the customer did their initial testing of this method there were no failures. This was because the customer did testing with a screw that had a different style of head (Pan Head), but still the same material. It was assumed that he could spec in a head design equivalent to the previous tapping screw for aesthetic purposes. This was not the case.
A bezel redesign was also suggested so that the bearing surface of the screw, when assembled, sits flush in the bezel. This would eliminate the need for the hardened screw with a special washer head and give the customer more readily available, standard options when selecting a fastener for future production.
A bezel redesign would also require a die redesign and since this issue was so time sensitive and a bezel redesign was out of the question, the Würth Engineering Team suggested that a hardened machine screw be used. The purposed screw is not a standard part and requires special tooling to manufacture. This incurred a significant lead time just to get the parts to the customer to test. This was going to push the customer past their original launch date by at least a month. Once the hardened machine screw was tested it was deemed acceptable for the application.
Würth Engineers Mitigate Lost Revenue and Find Cost Savings
The proposed hardened screw was tested and deemed acceptable for an immediate solution. This will reduce the amount of delay this product would have suffered, mitigating lost revenue. The bezel redesign will allow more standard fastener options, thus lowering the cost of the screw and giving the customer the most technically sound and economical assembly solution.
- 400,000 scrapped screws: $15,000
- 400,000 new screws: $22,000
- Additional testing/labor/scrap cost: $8,000
- One month bezel revenue lost (est. based on customer cost): $335,000