Spectrum finds niche in strip molding

If you want to stand out from the crowd, sometimes you have to do things very differently. That is how Spectrum Plastics Molding Resources of Ansonia, CT discovered its niche in the business of high-volume, precision strip molding.

Since its founding in 1967, says Spectrum President Pierre Dziubina, Spectrum has evolved into a leading strip molder, primarily because it designs and develops better equipment and technology.

Strip molding--also known as reel-to-reel molding--involves moving a carrier, metal or plastic, from one reel, through a multi-cavity mold where a plastic component is molded onto the strip, and onto another reel. Spectrum designs and engineers inline, auxiliary equipment systems for strip molding and creates its own presses by converting conventional Arburgs (28 and 40 tons).

"It hurts to bring in a brand new machine and start taking it apart, but that's what we do," says Tom Sloss, vice president of sales/operations.

The company's fourth generation of machines started with a new Nissei vertical with a four-tiebar system. The advantage here is that it can accommodate a larger mold base and thus more cavities, explains Dziubina. Currently, the Arburgs permit a 6-inch indexing stroke while molding two strips; using the Nissei, a 10-inch stroke can be attained, nearly doubling the capacity.

With 18 presses dedicated to strip molding, Dziubina says Spectrum is one of the best equipped strip molders in the U.S. "With our own design and ability to put things in line, we can be running one customer's item one day and another customer's part and system tomorrow," he says. The company can do a complete mold/system changeover in about 4 hours.

Some molds currently running have side actions, which makes the whole process even trickier. "Side action is not difficult to do in standard, loose piece molding, but in strip molding, the side action is actually going in and finding the lead contacts, which increases the risk for tool damage," explains Sloss. Hot runner technology from Mold-Masters is being used on some of the molds. "Often with molds used in this type of molding you can't put the probes close enough."

Application Innovations

Innovative applications for strip molding have given the company an edge with its customers. Spectrum recently received the Award of Excellence from Gillette Co. for its innovative solution to an assembly problem. Spectrum developed a method for molding small components for the Mach 3 razor on a Mylar film carrier. This helps Gillette avoid bowl-feeding parts in the assembly process, increasing productivity.

As a Hewlett-Packard business partner, Spectrum produces surface-mounted LED parts for H-P's manufacturing facilities in Malaysia and Singapore.

Spectrum molds a variety of parts primarily for the semiconductor industry and circuit boards, where the metal is an important component of the part. Parts are molded onto carriers of various base materials including copper with nickel or a precious metal such as gold or palladium. Stainless steel and Mylar are also used.

Applications generally involve small parts, even micromolding. One part the company molds is the size of the head of a pin. New applications for the process are always on the horizon. Dziubina says he wants to begin experimenting with molding onto a paper carrier.

The Process

The custom-designed carrier is brought into Spectrum pre-stamped. Using automatic feed and indexing equipment, the carrier moves from one reel to an additional die-stamping process prior to moving into the open mold. This all happens in sequence with the molding operation.

A vision inspection system checks the quality of the stamping to ensure it is to spec. If something is out of tolerance, the line automatically shuts down before the carrier enters the mold, so there is no possibility of mold damage; alternatively, the non-conforming stamping can be indexed through the mold, avoiding a splice.

Quality inspection of the carrier is limited currently to the beginning and end of every reel or at a splice section. However, the company's new Nissei system will have the ability to inspect all along the length of the entire reel, including automatically inspecting the product after the molding process.

"We keep on learning, improving, and adding to our knowledge as we go along," Dziubina says. Many other inline operations can be performed in this process as well, including additional stamping and forming operations and sub-assembly.

Additional Capabilities

In addition to the vertical molding presses, Spectrum operates three Cincinnati shuttle insert molding machines for non-automatic jobs. Spectrum also has Cincinnati Roboshot all-electric machines from 110 tons to 165 tons, Van Dorn presses from 80 tons to 170 tons, and Arburg presses up to 77 tons.

Spectrum's operations are set up in a manufacturing cell configuration. At the heart of each cell is a molding technician, an inspector, and an operator. "This is the heart of the company," explains Sloss. "Everyone in the company supports those people."

Spectrum's 85 employees are looking forward to the end of Jan. 1999. That's when the company plans to move into its new facilities in Ansonia. The 66,000-sq-ft plant--with room to expand to 85,000--will feature many amenities the 35,000-sq-ft plant just doesn't have room for, including a locked vault for storing the reels of precious metal and expanded areas for moldmaking, production, and administration.

Dziubina notes the company's niche in reel-to-reel molding has developed steadily. "We continue to take advantage of technology, to do our jobs as smartly as possible, and to turn out the best products we can," he says.