Two years ago, mold manufacturer Industrial Molds Group (Rockford, IL) began investing heavily in automation. The company spent nearly $2 million on new machinery, robotics and software to create work cells to obtain greater economies of scale in its 55-person shop.
"We have 100% coverage of all the processes that are automated," states Tim Peterson, Vice President. "Currently, 40% of our machinery is covered with automation, and 50% of our work volume is automated. Just about everything that touches plastic—core and cavity work—goes through an automated cell."
Lights-out machining at night and on weekends has been a huge benefit to Industrial Molds. The company operates one shift instead of two or three. "The way we've integrated automation [has allowed us] to be more flexible in the shifts," says Peterson. "We do core and cavity work unattended, which speeds up the time it takes to make large, multi-cavity molds and improves the quality and consistency of the cores and cavities."
Sourcing appropriate automation systems
Dennis Nord, Production Supervisor, notes that automating a mold manufacturing production floor requires evaluating your goals and the benefits you expect from automation. "We started by defining how automation will help us manufacture molds better, faster and more cost effectively. Automation for us has become the ability to run lights out even during the day by not having an operator standing at the machine," says Nord. "We were also interested in achieving more unattended run time through systemization—a real mold manufacturing system with automation—and more space between each setup, more interaction to set up tools and programs to be ready for the next run."
Determining the best equipment for automating the production process required Industrial Molds to look at different types of machines from different companies. Nord explains that when deciding on an EDM, they did a lot of test burning. "We wanted to see which company builds a machine with a good process to do extreme burns in our core and cavity work and maintain the accuracy we need," Nord says. "We had some extensive meetings with these different companies to determine which one could meet our needs. We're somewhat invested in Erowa, and while we looked at other systems, we ultimately chose Erowa."
For the wire EDM system, Industrial Molds decided that the most important factor was automatic threading. "Auto threading is key for us," Nord comments. "That's where we can gain efficiency, and so we went with Makino for this. It made sense for what we needed and we're able to thread through an open port rather than anneal the wire. We picked the U32j, which has been really good for our operations, as well as two Makino U6 Heat Wire EDMs. These new wire EDMs will run much faster and the consumables are more cost effective in that they use less wire."
Next, Industrial Molds began evaluating high-speed machining (HSM) centers. The Mikron HSM 400 ULP 5-axis electrode cutting machine doubled the company's electrode production. The newest carbon cutting machine is connected to a robot that operates with a second carbon-cutting machine. A silo that holds 220 electrodes can run lights out for a long period of time in the state-of-the-art manufacturing cell.
The company's OKK HM 1000s horizontal mill purchased in Q4 of 2014 has been installed and is running. It has a 60-tool changer, and the higher RPMs allow Industrial Molds to run jobs back-to-back and increase lights-out operations for the mold base area.
A shift in culture
Installing new equipment and automation to create work cells is just the beginning. "When you buy new equipment, you have to adapt to the system and learn to be profitable with it," Nord explains. "When we bought the new Mikron 400 ULP for doing hard milling and carbon cutting, we bought equipment that took us to the next level in terms of speed and accuracy. We can do very accurate cutting, and with the OKK horizontal with 2 pallets, we can now set up parts while we're milling."
That means that the machinists and moldmakers on the production floor need to adapt to a new culture of machining. "It's human nature to do what we're comfortable with, but while we're doing the same things we did before—pallet-to-pallet changing, 5-axis hard milling—we're working with equipment that has greater capabilities and is faster and more accurate. That requires a change in the culture. We can't run this new machine like we ran the other machine. We need to push the limits and take it to the next level, and that's how we've been successful."
Nord notes that the production machinists and moldmakers have endured a lot of change with the automated pallet systems, running pieces back to back in different machines, preparing everything before it goes into the machine. "It's a different way of working with the machines," says Nord. "A guy is not necessarily standing in front of a machine making chips, but rather putting pieces on pallets in a queue."
While Industrial Molds' younger employees see automation as the norm, some of the long-time moldmakers and machinists can be reluctant to change. "But we need to push ourselves to see the consistency in our operations; to see the end result of higher precision and better quality," Nord adds.
"We're already seeing benefits to our automation, and over the next few weeks, once we get everything integrated and up and running, we expect to see many more advantages," he says.
One advantage is that the company doesn't run multiple shifts anymore, but instead runs what it calls "flex shifts" by moving second shift to more flexible hours. "Mold shops have strange demands from customers and there are times when there are no set stop/start times for the guys, so we empower the guys to plan their jobs and machine setups according to the requirements. If it takes longer one day to get it done, then they can come in later the next day. This give and take—this flexibility—goes a long way."
Benefits of automation in building high-cavitation molds
One of the most critical factors in building high-volume, high-cavitation molds is the cavity-to-cavity consistency and repeatability that is required over the life of the mold. Account manager Randy Hanson has many years' experience in overseeing tooling projects, including mold qualification and process validation. Recently, Hanson has directed projects involving 32-cavity, high-volume molds.
"There are a number of advantages to automation in a mold shop. Because of the complexity of these molds and the parts, the moldmakers have to make sure that our cavities are 100% consistent cavity-to-cavity," Hanson states. "With large-cavitation tooling, it's far more important that dimensionally you're extremely stable. With the implementation of automation, we can achieve the dimensional stability we need when making these large-cavitation molds and the spares. The rule of thumb for high-volume medical molding is typically 25% spares. Anything that touches part geometry, the customers want spares, and those all need to be qualified up front with the mold."
Spares are critical for large OEMs with global operations because of the interchangeability issues. Using automation to build cores and cavities provides the required dimensional consistency if a core/cavity breaks and a spare is required. Automation removes some of the human error that might occur when these components are built manually.
Hanson points out that one of the difficulties with building tooling offshore is that if you build a 32-cavity mold, you might have 32 guys working on core and cavity sets--each one building a core/cavity set. "When you run spares, you can't take the time to hand fit the spares to the tools," Hanson says. "This is a real change from traditional tool making, where we're used to fitting blocks. If you're making large-cavitation molds with spares you can't do that. Everything has to be exactly to the numbers for total interchangeability. That's what our automation with its precision repeatability does that others can't do."
For a large production mold company like Industrial Molds, automation offers huge benefits in time and labor. Peterson states emphatically: "The biggest benefit we realized is the ability to run lights-out—all night, weekends and holidays. The way we've integrated our automation allows us to have more flexibility, yet automation has forced us to be systematic and methodical in the way we do things. Our quality has improved tremendously."
When it comes to growing the business, Industrial Molds sells value. "The automation helps us sell value," Hanson adds. "We're more capable, which allows us to provide more value for the dollar. At the end of the program's life, when they've run the mold for 10 years, we believe we've provided a better tool, added more value through automation."