Blow Mold Maker Turns to Makino
Technology to Make a Difference

Few companies in North America are capable of making bottle molds for the specialized stretch blow molding process. Hammonton Mold Co. Inc. of Williamstown, New Jersey, is a full-service mold shop that specializes in this process for plastic bottle manufacturers, as well as molds for the injection blow mold industry.

But, regardless of the level of competition, Hammonton believed it needed something to set its company apart from the rest. The company recently took delivery of a Makino V33 vertical machining center, the performance of which Hammonton owner Luka Domazet says generated an immediate 50 percent savings in time. And Luka is encouraged that they will see even more savings down the line.

Hammonton often tackles projects that other mold shops turn away. Much of the company's growth stems from its ability and desire to design and build custom molds in unusual shapes. "You need a machine like the Makino to do molds like these competitively," Luka says. "Anyone can make a square bottle. It is our ability to make the unusual shapes that helps us win business over and over again. The Makino V33 makes that happen."

Old World Quality [back to top]
Luka Domazet began his career as a mold maker as a teen in his native Croatia, producing molds for shoes and tires. He came to the United States in 1974, and went to work for a friend from his hometown who was making molds for plastic injection-molded bottles.

He stayed with his friend's company for 12 years until deciding to strike out on his own. Luka's brother, Josip, is the shop foreman. His two sons, Ivan and Steve, also work at Hammonton.

Today Hammonton produces molds for bottles used in the pharmaceutical, medical testing, personal care products, food and beverage, cosmetic and scientific container industries. Some of the company's customers include Johnson & Johnson, Owens Illinois, Silgan, Colgate Palmolive, Tupperware and a variety of other customers including cosmetics companies.

In the stretch blow molding process, bottles must meet a variety of criteria for the industry they are primarily used in—packaging of carbonated beverages. Because the process requires multiple operations, it is very stressful on the bottles and requires precise molds to ensure the integrity of the bottles.

A few years ago, Hammonton hired a designer to work on-site to create molds for stretch blow molding. Prior to this, few shops in the U.S. had an on-staff designer, and many industry projects were designed and built in Japan. By adding an in-house designer for this process, as well as continuing to invest in new equipment like the Makino V33, Hammonton has stayed poised for success as the economy rebounds and its customers' needs accelerate.

One example of the company's innovation is in the design of a retractable bottom plug mechanism for injection blow mold tools. This patent-pending mechanism, called Black Ice™, can be retrofitted to an existing tool, or ordered as part of a new one. Essentially, what the device does is bring direct cooling to the bottom surface of the bottle while operating with a nearly frictionless and linear movement. Coupled with extreme rigidity and a compact size, Black Ice™ overcomes the "maintenance nightmare" that Hammonton was hearing about from its customers that was inherent with older designs.

Customer Partnership [back to top]
The Domazet family positions Hammonton as a partner company to its customers. Not only does the company make molds, it offers full- service engineering and consulting to customers that require it. Hammonton is always looking for better or more efficient ways to do things within its own shop, as well as for its clients. Hammonton uses Pro/Engineer Wildfire software from Parametric Technologies exclusively for its design and manufacturing software.

When shopping for a new vertical machining center, one attribute that Hammonton sought was a fast and rigid spindle. "We compared the Makino V33 to a few of its closest competitors in the market today," says Luka. "We found that on the other machines, the high-speed spindles needed to be replaced or repaired at approximately 3,000 hours.

"Replacement of a spindle is very costly. And, you have downtime whenever your spindle needs repair. We can't afford that kind of downtime with the volume we are running through the machine." His son Ivan added that the spindle core cooling on the Makino, along with the large ball bearings, were major factors in the decision to make the purchase. He concluded that spending more on the Makino was worth it.

Ease of Operation [back to top]
The Makino has also been easy to learn, though Luka says that some of the machinists were intimidated by the V33 initially. "Once they are comfortable with it, we plan to add more options to the machine. Eventually maybe we'll buy another, bigger Makino."

In fact, the Makino is so easy to use that Luka's son, Steve, who had no previous experience running a vertical CNC machining center, is one of two people in the shop who operate the machine. He notes that many molds at Hammonton are machined on the V33 and finished significantly faster than they were before.

"From start to finish, for the three-dimensional work in our mold making area, our molds can take anywhere from 15 minutes to two hours depending on the complexity of the mold," says Steve. "With the Makino, we are saving time not only in cutting the molds, but in our benchwork because of the quality of the finishes we are getting."

Programming Change [back to top]
The Domazets agree that since adding the Makino to their shop, they have had to change the way they approach programming—and often, even the way they think about things. They have a number of other CNC machines in the shop, but none that are as precise as the V33.

Steve says they used to machine their cavities to within 0.002 inches of the final cut, and then finish polish the molding area to specification. But, with the precision of the V33, they no longer have to do this. Because the whole process can be completed on one machine, in one program and by one operator, there is much less margin for error. He says that they have found it is also worth the time to use a Renishaw touch probe—added as an option on the V33—on every job to assure that the set up is correct before proceeding with cutting, which also helps reduce errors. Hammonton also uses a Blum laser to verify the length and diameter of each tool before cutting.

Hammonton recently completed a mold for a very unusually shaped bottle that is difficult to produce. The bottle is approximately 12 inches in height, is triangular at the base, and has a twist that begins midway up the bottle and continues to the neck. This unusual shape took some creativity in programming and Hammonton is proud to have won the business as the only shop that could produce a mold for this particular bottle.

Since installing the Makino, business has been booming. "We are very busy right now. That's why we decided to buy the Makino. We couldn't keep up with deliveries the way we were working before, but now we are doing great."

Hammonton Mold Co., Inc. can be contacted at 4171 South Black Horse Pike, Williamstown, New Jersey 08094. Phone: 856-728-9112; Fax: 856-728-1432; or online at www.hammontonmold.com.

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