"We design all the hardware coming off the hardware division relative to printed wiring boards...flex harness and rigid flex harness," he says. The former, he explains, is wiring printed from copper, designed to replace wiring in projectiles and missiles. Rigid flex is a combination of a complex printed wiring board and a flex harness.
"Martin has the patents on building rigid flex," Mc Eachnie says, "and started out using the technology primarily for aerospace. Now it's migrated to other industries, particularly automobile manufacturing."
At Martin Marietta, both open and closed CAD systems exist. The open systems have circuit engineers working on a CAD Apollo terminal connected to Mc Eachnie's operation by hard line and read directly back and forth by a local area network (LAN). "We're connected with a DEC or VAX network in Martin," Mc Eachnie explains. He says there are approximately 60 Apollo systems, with the company buying more. "Engineers just go and find a terminal when they need them," he says.
The closed system Mc Eachnie supervises, however, is a different matter. Here, operators work on CAD systems: Computer vision or Sci-cards, a sophisticated CAD program for designing printed wiring boards fairly automatically. After design, Mc Eachnie's people give the required data to Manufacturing to build, whether it's wiring board, flex harness, or rigid flex harness. "We don't have any tooling people involved anymore," he explains. "We run directly all the equipment that manufacturing needs to build a part."
"We designed all the cards we need for post-processing...a complex program we've been using for the past seven years," he says. "Every design we do goes through the post-processor to initiate all the intelligence that manufacturing needs to build a part. We also give set-up sheets, so operators even know what tool to put in what position before they start the machines."
At Martin Marietta's Orlando facility, "The mechanical side of the house," says Mc Eachnie, "does things a little differently." Although they have used a CAD AM system for 2-D drafting for over five years, the division is switching to a 3-D Application system. "All our designs several years down the road should be on the 3-D data base." he says. "We'll be feeding them directly into production machines, running on 2, 3, 4, 5, 6, even 7 axes, so we have very little problem going into tooling."
Mc Eachnie explains that the advantage of switching to a 3-D system is in the output "what you get downstream." With 2-D drafting systems, he says, you still have to look at drawings. Engineers have to do manual tooling, setups, and numerical control (NC) tapes. With 3-D modeling systems, however, engineers can take data directly off and feed it into production machines, thus eliminating a number of manual operations. 3-D systems also give design people the chance to do checks of fit and tolerance.
Mc Eachnie remembers a case several years ago. "We designed an in-depth type of projectile, using a 3-D CAD system," he recalls. "When we put it together using the CAD system, we found there was an interference-discovering the subtle tolerance difference before we built any parts. No one would have caught it, except for 3-D CAD, but we were able to fix the problem and move ahead. There are engineering and manufacturing gains in 3-D," Mc Eachnie believes, "but the downstream designs provide the real savings."
Cad Jobs at Martin Marietta
At the Orlando, Florida facility on Sand Lake Road, (there's another Martin Marietta plant across town), Mc Eachnie says they're still "We designed all the cards we need for post-processing...a complex program we've been using for the past seven years," he says. "Every design we do goes through the post-processor to initiate all the intelligence that manufacturing needs to build a part. We also give set-up sheets, so operators even know what tool to put in what position before they start the machines."
At Martin Marietta's Orlando facility, "The mechanical side of the house," says Mc Eachnie, "does things a little differently." Although they have used a CAD AM system for 2-D drafting for over five years, the division is switching to a 3-D Application system. "All our designs several years down the road should be on the 3-D data base." he says. "We'll be feeding them directly into production machines, running on 2, 3, 4, 5, 6, even 7 axes, so we have very little problem going into tooling."
Mc Eachnie explains that the advantage of switching to a 3-D system is in the output "what you get downstream." With 2-D drafting systems, he says, you still have to look at drawings. Engineers have to do manual tooling, setups, and numerical control (NC) tapes. With 3-D modeling systems, however, engineers can take data directly off and feed it into production machines, thus eliminating a number of manual operations. 3-D systems also give design people the chance to do checks of fit and tolerance.
Mc Eachnie remembers a case several years ago. "We designed an in-depth type of projectile, using a 3-D CAD system," he recalls. "When we put it together using the CAD system, we found there was an interference-discovering the subtle tolerance difference before we built any parts. No one would have caught it, except for 3-D CAD, but we were able to fix the problem and move ahead. There are engineering and manufacturing gains in 3-D," Mc Eachnie believes, "but the downstream designs provide the real savings."
