EASTLAKE, OHIO — Heard of extreme sports? An Eastlake rotational molder qualifies for a gold medal in extreme product development.
Working with mold maker Wheeler Boyce Co., rotational molder Enpac Corp. turned an idea into a finished part during a lightning-fast, 12-day period.
Enpac had a very tight deadline. The molder of safety products for secondary containment and spill protection hoped to display the new product at the Industrial Safety Show last October. But there was a slight problem: That show was in two weeks, and Alan Girard, Enpac design engineer, had only just dreamed up the idea.
Although the product was fairly simple, the time constraints got everyone pumped up. Girard recalled ``the sheer adrenalin rush of trying to get a part for the show in two weeks.''
Wheeler Boyce used a new technology for rotational molds — cutting the molds from a block of aluminum with a computer numerically controlled machining center, instead of the traditional cast aluminum molds.
It started Oct. 8 at the Association of Rotational Molders' fall meeting in Chicago. Just before the meeting, Clark Boyce, a Wheeler Boyce sales representative, had told Girard about the company's CNC technology, which could make molds much faster than the casting method.
Girard stopped to chat with Boyce and another Wheeler Boyce salesman, Mel Bechemer, during a conference break. Girard said Enpac was getting into a whole new market: products for handling cylinders of compressed gas, such as propane. The new line would debut at the upcoming Industrial Safety Show.
Girard told them his idea: rotomolded brackets to hold tanks against a wall.
``These were ideas still. They weren't even on paper yet,'' Girard said.
He asked whether Wheeler Boyce could do it in time.
Boyce and Bechemer headed straight to the pay phones and called their office in Stow, Ohio. Wheeler Boyce had the machine time. Part dimensions checked out.
Back in Eastlake, Girard dug into his computer's Pro/Engineer design software. It took just 45 minutes to design two models of the ``poly-cylinder bumper bracket,'' one to hold a single tank and a model to hold two tanks. Each one needed a mold.
At a special meeting, Enpac officials approved the product. The designers created a translatable file on Pro/E, and e-mailed it to Wheeler Boyce.
Girard recalled: ``I got back from the show on a Wednesday, had the design and engineering done on Thursday, made the revisions on Friday and then e-mailed Friday evening before I went home for the day. They had it in their system on Friday evening.''
Wheeler Boyce took nine work days to cut the molds, then Clark Boyce drove them to Enpac in the Cleveland suburb. Enpac molded parts the next day.
``That was one day before the show,'' Girard said.
He drilled holes in the yellow cylinder holders and attached black straps.
Wheeler Boyce subsequently made two more molds for the cylinder-handling product line —a mold for a pocket to hold tools on a wheeled dolly, and a modular bracket system. They took 21 days — more typical of the three- to four-week lead time for CNC machining. It takes about six weeks to build a cast aluminum mold.
Wheeler Boyce got into CNC machining about two years ago, buying its first vertical CNC machining center to make molds for aerospace parts, said Julie Stout, marketing manager. The company took delivery of two more of the Johnford machines in the past six months.
Cast molds require a wood model, the use of sand and quite a bit of handwork. The CNC machines can run automatically 24 hours a day.
Another advantage of CNC machined molds is parting lines that fit together precisely, Stout said. Finishing work is required on cast aluminum molds.
Because cast molds for rotomolding tend to deflect under pressure, mold makers construct elaborate support frames, known as spiders, to hold the mold tightly closed. Machining from a block of aluminum means CNC machined molds are less prone to deflection, Stout said. That means a simpler spider with less clamping pressure is OK.
Enpac, a division of Essef Corp. of Chardon, Ohio, runs four rotomolding machines at its 70,000-square-foot factory.