Metal/plastic fastener secures design award

Cleveland--It's rare today that you hear about plastics and metal joining forces in the design of a new product. But that's just what Thiel Tool & Engineering Co. (St. Louis) did in introducing a new electrical fastener for residential use. As a result, the company walked off with the 1998 Ulbrich Award for Competitive Excellence in Product Development, presented by the Precision Metalforming Association.

The scenario went something like this: Recently, some state and local electrical codes for home construction have encouraged manufacturers to make product changes using plastics and fibers. Thiel wanted to comply with the new codes, while retaining the strength of steel fasteners.

The company's R&D team consulted with different specialists, including electrical engineers and inspectors, as well as experts from the construction industry. Suppliers were asked to provide user-friendly coating materials, as installers have been known to "lip-stage" the staples.

When it came time for mechanical planning and fabrication, an East Coast machine builder known for his expertise in original designs was contacted. Thiel's team worked with the designer, the plastics industry, and small parts handling/positioning engineers to develop a one-of-a-kind proprietary process that keeps the steel part, but coats the top half of it with a polyvinyl chloride-fused insulation.

The team's work resulted in a machine that loads and unloads 950 magnetic fixtures automatically while in continuous motion. A key feature of the process revolves around the synchronous movement of liquid and steel to create a "still" dipping pool. This represents a totally new concept to the industry, according to the award judges.

Production requires only a 30 to 50% attention factor. This allows the machine operator to package orders and handle material as the line runs in an automatic mode.

The finished product provides electrical short-circuit protection to 5,000V. If the insulated staple is driven with excessive force, or at an angle, and ruptures the nonmetallic jacket of the residential cable, it still will not cause a short circuit between the exposed copper conductors.