Making Complex Tools Look Easy

When Dennis Rippetoe, president of Crucam (Livonia, MI), is asked to describe the types of molds his company produces, he responds, "The complex and the intricate." Crucam started out as a service bureau for developing CNC cutter paths for the mold and die industry. Six years ago, the company saw a need for machining as well, and today, 80 percent of the business involves plastics injection molds. Most of Crucam's customers are generated through referrals and word of mouth. There is no direct sales force to market the company's services. In fact, if it can't meet a job delivery date due to overcapacity, it has to turn business away. What's the company's secret?

"We've got about 40 workstations running Camand software from Camax for creating surfaces and NC programs," says Rippetoe. "The work we're generally performing is fairly complex in nature. If it weren't, most of our customers would do the work inhouse. Complex, multiple, intersecting, and blended surface parts require complex molds with slides and lifters. Over our history, these are the kinds of projects we normally get, especially because of our close location to Detroit. We've developed a specialty in speaker grille molds, designing them so that resin flows around all of the holes. This is an area where consistent wall thickness is essential to making thinner walls and getting better sound out of the speakers."

Before Crucam gets involved in a project, customers typically scan a model or create a CAD model. "Most frequently we're supplied with an IGES file from the automaker's internal CAD system or from the Tier One supplier's system," says Mark Slack, operations general manager. "This is where Camand has a leg up on the competition because it translates IGES files from any CAD system with great accuracy." Camand is used to create any additional surfaces required for machining. The next step is mold design, finding the best parting line conditions, gating locations, and runner configurations. "The biggest thing we find with Camand and cutting from CAD data," says Slack, "is the consistency in wall stock. Consistent wall stock means optimum mold flow."

Crucam has a range of machine tools, 21 total, including four Charmilles EDM machines. Machining can be done on a three- or five-axis gantry mill. "On one particular job," says Slack, "we determined that it would take us two weeks on a three-axis machine because of the different setups required. But with the five-axis machine programmed via Camand, the mold took us only four days to complete. We were able to cut eight days off the delivery date."

In another success story, Crucam was involved in producing three prototype aluminum molds, one of which was two-cavity, for an automotive application. After Crucam delivered all four tools in 10 weeks, the Chrysler customer called to ask how it kept the tolerances so tight--all four parts fit together perfectly.

How about the learning curve with CAM software? Rippetoe reports, "We've set up an internship program with Livonia high schools. Students learn to program, go onto the shop floor for several weeks, and also work with our service technicians for a few weeks. We put the program in place about three years ago, and many of the students either go to work for us or for our customers. We have one who graduated a year ago from high school who can keep up with many of our senior operators."

Crucam is an authorized training center for the software, and normally, training takes two weeks to cover modeling and NC methods. In smaller shops, Rippetoe notes, it is difficult to give up a key person for two weeks. "So we've condensed the training to one week and focused on the skills necessary to define models and cutter paths. We've also done this for the high school students along with the tutorial that comes with the software. It's amazing to see how quickly these kids are able to build surfaces using the software, and Camand supports this effort."

Rippetoe believes there is a dire need for this type of training in the moldmaking industry, which dropped its apprenticeship programs during the recessionary period in the late '70s. "Our interns, after graduating from high school, can earn about $25,000 per year, and in four years, salary levels are more than $50,000. This program has been such a success for us and our customers that we have entered into a similar program with Schoolcraft College in Livonia."