SOUTH ELGIN, Ill.—The rubber industry is still playing catch-up to its counterparts in the plastic industry, including its approaches to tooling, said John Fleming, owner of Hamilton Mold and Machine Inc.
Fleming presented "Tooling Trends in the Rubber Industry" at Machine and Planning Inc.'s (Maplan) Days of Technology, June 5, at Maplan's new facility in South Elgin. Hamilton builds rubber molds and liquid silicone rubber molds, with a focus on automotive customers, as well as electrical applications and consumer products such as pet toys.
"We continue to follow the plastics industry," he said in a later interview. "The plastic industry has done a good job in standardizing their platens and their mold bases. The rubber industry, they're buying into automation more and more, but we still haven't completely standardized our press platens."
Another example is hot runner processes, which are more prevalent in the plastics industry, but are only recently starting to show up with similar technology in the rubber industry, he said.
One reason the rubber industry is not at pace with the plastics industry is the overall volume of parts in the plastics industry, Fleming said.
"The plastics industry is so much bigger, there's so many more plastic mold makers that they drove innovation to stay competitive," he said. For rubber, that number is much lower. "There's a lot of rubber mold makers that just want to supply whatever the customer had 10 years ago."
Increasing automation
Standardization is another factor driving the plastics industry forward faster, as well as an embrace of automation, he said. Integrating automation into rubber processes isn't just about the design of the mold or the robot. Sometimes it means looking at the features of the product design itself that can lend to automation, such as adding something that can be pushed or pulled on to help demolding.
Using automation in rubber also can mean looking for the right situation where it makes economic sense to do so, he said.
"We have some customers who, their culture dictates that they're going to make this particular widget as efficiently as they can. And then there are some that just say we need to make this as cheap as we can," he said. "You kind of don't see the trees for the forest by making an inexpensive tool and having labor added. Maybe there's additional labor cost because they're handling the part more later on."
Fleming does see automation as a trend in tools for rubber production, but that trend can cut both ways, he said. While some are using it to find better efficiencies, others try it and back off to find what the company wants to focus on.
"The local mom-and-pop shop is sometimes more afraid to make that capital investment for automation," Fleming said. "It's harder for them to see the benefits of that. They need a contract for a long-running part. If they don't have that, they're not going to put automation in."
Labor rates also play a part in increases in automation, as the process looks more appealing as those rates increase, he said. Even with a significant investment, the return on investment can happen quickly.
"If you have to invest $50,000 to make something automated, it's going to pay for itself in probably a year or less, because your cycle times are repeatable, everything's more predictable and nobody's taking a break," he said.
Precision molding
Fleming has seen an increase in talk about trying to control, predict and manage flash. Though he doesn't advocate flashless tooling, he said it's possible, provided that the company has the personnel resources to manage it.
"If you want to pursue flashless molding, you have to have the people in your house who are dedicated and committed to it day-in and day-out," he said. "When you're trying to make precision parts, you need to have precision people."
For example, if a heater goes out on a rubber mold, one section of the mold will begin making bad parts. Without someone in the building who can quickly dissect the problem, it could take longer to resolve, he said.
"People will say, 'What happened to the process? Why is this mold flashing?' If it's 2,000 miles away from me and it's a blown heater, it's hard for me to figure out," Fleming said.
The industry is trending toward more precision molding in operation, a major difference from even 10 years ago, he said.
"I have a lot of customers who want me to build them a mold where they don't have to handle their parts at all," he said. "They want it to run fully automatic."
Returning operations
A trend that's slightly less strong but still visible is a change in cavity counts, he said. Some customers run high cavitation numbers, from 64 to 128. But for some similar parts, where one customer has a 64-cavity mold, the other has multiple 4-cavity molds.
"It's the exact same part, but they're approaching it a different way," he said. "The 4-cavity mold is a very high-precision molding. They brought in automation, and had a couple of these cells running more or less lights-out.
"For the 64-cavity mold, there's an operator front and back, demolding. Yeah, you get a lot more parts every 90 seconds, but there's a lot more handling of the part by a person."
Much of that split comes between the U.S. and Mexico, he said. Labor rates in Mexico allow more molders to have multiple operators, whereas the U.S. often aims for more high-precision molding processes.
Fleming also sees non-automotive customers bring operations back to North America from overseas, with about a 50/50 split going to the U.S and Mexico each, he said. About 15-20 percent of Hamilton's sales for 2017 were made up just of reshoring customers.
Bringing those operations back usually includes some changes in how the parts are produced, he said. Customers often have found their problem points during overseas production, which calls for improvements. Also, many customers make the switch from compression molding to injection molding if possible.
Despite the trends, tooling in the rubber industry is still a very customer-specific business, where no single solution is going to fit every molder, he said.
"The one thing I really wanted to emphasize is that one size doesn't fit all. It's who you are as a company," he said. "What's your company's culture and expertise really dictates the path you're on to move forward."