Are you ready to design 
in three dimensions?

Moving from 2D to 3D hasn’t been easy or painless for moldmakers and molders, but the design and manufacturing world is quickly moving to 3D. Here’s how one company did it, along with some timely tips for going full 3D.

While Taiwan-based Megaforce Co. Ltd.’s quality and efficiency in mold design have been market tested over the company’s nearly 20-year history, the traditional approach of deploying both 2D and 3D CAD engineering software increasingly fell short of where the company wanted to be, particularly in terms of mold quality and the processes used to design and develop these molds. The problem was compounded when larger molds were needed for products like big-screen LCD TVs. In these instances, the company wanted to improve surface precision and the integration of design, production, and drawing management.

There are dozens of 3D CAD software systems on the market, and before going full 3D, Megaforce had used several different kinds. Integrating mold design and manufacturing processes was key to the company, so it decided to move away from multi-brand design software and adopt one: Siemens PLM Software’s NX software.

As a first step, Megaforce assembled a task force to focus on its new 3D mold design capabilities. It then implemented a system-wide approach that used NX modeling and its engineering drawing capabilities to meet the company’s mold design requirements. During the introduction of NX, the tool manufacturer resolved a variety of issues related to system configuration, modeling methods, drawing techniques, kinematic mold analysis, and secondary development.

Solutions with 
single-sourcing
Missing data is a problem that plagues mold designers using multiple CAD software systems, since often part prints from customers arrive in incompatible formats. Solving that problem was one of the first benefits that Megaforce derived from deploying Siemens NX software. The company saw a reduction in missing drawing data, a problem that  had previously inhibited the company from executing its drawing documentation quickly.

After improving this process, the mold department was able to produce more accurate layouts in a timely manner, which enabled the company to provide its customers with full 3D mold documentation. A side benefit was that communication between the designer and the user improved and mold designs were finalized much faster.

“A key to the long-term cooperation between Megaforce and our clients is their trust in our ability to design and develop molds,” says Steve Lin, executive VP, IV Manufacturing Center of Megaforce. “Our full 3D design environment, which is based on NX software, enhances our design and manufacturing quality, shortens our development cycles, and caters to our clients’ new process and product launch schedules.”

Megaforce’s full 3D environment also sped up the drafting process. Using the traditional design approach, major tasks could only be carried out in a linear fashion. The full 3D design procedures that Megaforce developed with NX enable the company to execute these tasks simultaneously. As a result, Megaforce is able to perform mold assembly drawing, 3D part drawings, mold base design, and the design of the slide/lifter/cooling channels of the same mold through multiple design members collaboratively.

Vynce Paradise, NX CAM marketing director for Siemens PLM Software, says that NX makes converting from 2D to 3D easy, thanks to the latest version of NX with its DraftingPlus solution. “It enables the user to easily map 2D views into 3D cross sections that can be used to build 3D models very quickly, and facilitates editing by converting the 2D profiles into sketch geometry,” Paradise explains.

For moldmakers, the advantages of using the NX 3D solids-based design include helping tool designers clearly visualize placement and fit of molding components within a 3D context of the mold base. “And, because the design work is done in 3D, downstream NX applications such as 3D solids-based kinematic interference checking and CAM can directly use the original design model—without any extra modeling work,” he states. “Moldmakers can easily capture company standards [definition of standard parts, drawings, etc.] inside of NX and reuse them to achieve increased speed and accuracy.”

Megaforce has realized these benefits and more. “In the past, when we used other CAD software, we could process and output only one drawing at a time,” Lin says. “It was not efficient enough. By using NX and the full 3D functions compiled by Megaforce, we are able to use one single instruction to send all of our drawings to the printer queue for output. The system automatically adjusts the size of drawings for optimal output and saves a great deal of time.”

Interoperability issues
Sandy Joung, senior director of product marketing for Parametric Technology Corp.’s (PTC) desktop CAD products including Pro/Engineer, says that with Pro/E, “we’re trying to be as flexible as possible” in accommodating 2D designs. “2D has been around for so long and people know it so well, and it’s fast and easy for simple designs with no complex assemblies, that we need to be able to import that data into 3D with Pro/E,” she says. “Sometimes users receive data from competitive 3D products, so Pro/E is very open and interoperable in providing data exchange with 2D.”

Pro/E makes it easy to transition from the design to how the product must be manufactured. Pro/E Expert Mold Base Extension uses product data that was created in Pro/E or in another CAD program to automatically create an entire mold assembly. “Pro/E knows how and where the mold should fit,” explains Joung. “It can do analysis and simulate what will happen in manufacturing through an FEA of the actual mold assembly and tell you how long that mold piece will last, [as well as] check thermal dynamic properties of the mold and even material flow analysis. You can actually do the design of the mold assembly in 2D—design the cross section of the mold assembly—and then optimize that in 2D and parametrically link it to the 3D modeling system.”

Moldmakers don’t necessarily have to go to full 3D, but that wasn’t always the thinking. “A few years ago we’d have said ‘just go to 3D,’” says Joung, “but today we see that for a CAD-savvy person, 2D is just easier. Some systems like our CoCreate are very fast and not constrained for 3D, and PTC’s products support both 2D and 3D. We’ve also seen a lot of conceptual engineering work—a step beyond 2D work—that is very detailed engineering work in 2D before it gets converted to a 3D model. To the extent 3D products can support that type of design process is very important.”

Joung recommends that when moldmakers consider going to full 3D, the optimum way to evaluate the software is to determine which ones support your legacy data. Does the 3D modeling system support the 2D? “Even within our CoCreate family we have pretty robust 2D [software] as well as the 3D modeling,” she adds.

Evaluating 3D 
CAD systems
Gary Lamit, a 30-year manufacturing industry veteran and full-time instructor and department head at De Anza College (Cupertino, CA), has written 30 books on CAD, many of them in partnership with PTC. He offers some tips on how to evaluate 3D modeling tools in his book, Moving from 2D to 3D CAD for Engineering Design (2007 by BookSurge and MobiPocket eBook).
Lamit, who also owns a company called CAD Resources, notes that while all 3D CAD systems may look similar, the differences between the various systems can be extensive. The key to success, Lamit says, comes down to evaluating how effectively a 3D modeling system addresses the fundamental transition concerns:
• Productivity (usability and “learn-ability”)
• Legacy (2D design data)
• Cost (total cost of ownership and cost of use)

“By addressing these concerns in detail, the engineering manager can compile a short list of 3D software candidates that will represent the best choices in their 2D-to-3D transition strategy,” writes Lamit. “The list will reaffirm the answers to the question, ‘Why change?’ since so much of the list expands on the usages of the 3D model database when compared to the traditional 2D design document.”

Another factor, scalability, encompasses many areas, including:
• Extended design (mechanisms, large assemblies, and industry-specific applications)
• Downstream capabilities and functionality (analysis, mechanism dynamics, animation, rendering, inspection, testing, prototyping, CAM)
• Data management (data vaulting, change management, collaboration, configuration management, bill-of-material management, MRP, ERP)

Lamit looks at each of these and offers some tips for evaluation:
• Usability and learn-ability
1. 3D software should be simple to use and understand, modern, and familiar,
2. The best 3D CAD tools should provide powerful capabilities in a scalable, easy-to-learn, easy-to-use package.
3. The best 3D CAD tools should allow designers and engineers to spend their time delivering great products instead of learning how to use the tools.
4. The 3D CAD system must feature comprehensive, built-in tutorials and online training options to allow users to learn at their own pace.
• Legacy data. Does the 3D CAD system have an available internal, integrated program that will allow the use of 2D data directly as control geometry for 3D features?
• Cost
1. The typical cost of entry-level 3D software can be misleading, since the total cost of ownership is the important factor, and takes into account the cost of software, training, and customization, plus the cost and quality of support.
2. Cost will also include the purchase and installation of new hardware (and hardware maintenance). “Although hardware is not a hidden cost, training costs can be misleading and more complex than presented by some software manufacturers,” Lamit warns.
• Extended design. The need for a scalable 3D growth path is a critical consideration, which is why entry-level 3D CAD systems are not usually considered appropriate for advanced design work. “Over time, users will quickly encounter the limits of their technologies,” says Lamit. “For instance, a designer may want to work with more complex geometries or manage 3D assemblies.”
• Downstream capabilities. Does the 3D CAD system allow for “the use of an original part database for concurrent engineering processes, which allows for downstream deliverables like mold cores and cavities, and NC toolpaths to be developed even as the design of the product is still evolving?” Lamit poses. “Through seamlessly integrated, associative CAD, CAM, and CAE applications, these deliverables can automatically update, even when changes are made to the design very late in the process, including manufacturing.”

In conclusion, Lamit notes that moving from one design tool to another will not be without its challenges. “Going into the process requires that you and your team have every available transition tool, along with available outside assistance that you trust, and the support from those above you in upper management and below you in your engineering, design, and manufacturing workforce.”

Tips for going full 3D from 2D
A whitepaper from SolidWorks Corp., “Bridging the Worlds of 2D and 3D CAD Design,” notes that 3D CAD design has many inherent benefits over working in 2D:
• Improved product visualization and presentation.
• Automatic and accurate updating of parts and drawing views.
• Automatic interference and collision checking—an error-free way to check for interferences and collisions before manufacturing the product.
• 3D does not have to be an all-or-nothing process—you can keep existing designs in 2D, and then transition them as needed into the 3D system.

In making the transition, some engineers might ask what they should do with the existing 2D data they have been developing for years. And what about customers that still communicate in 2D? SolidWorks says that engineers may want to keep and maintain existing 2D CAD files on a computer that provides access to these as needed. If you do not want to pay for the maintenance of the 2D CAD product, SolidWorks vendors may offer a free copy of DWGeditor 2D design software with the purchase of SolidWorks. DWGeditor allows users to maintain and update existing 2D designs, and save them in the .dwg format.

SolidWorks can also output drawings and images in multiple 2D formats, even though the user may be designing in 3D. This means that users can still output documentation that is compatible with all the common 3D formats, such as DWG, DXF, PDF, and JPEG.

What you should know about 
3D CAD software
If design changes, updating and optimizing old designs, and ECOs are consuming your time when you could be creating new mold designs, then perhaps you’re using the wrong software, says PTC, developers of Pro/Engineer. The company offers some tips on what you need to know about 3D CAD software.
1. Easy-to-use 3D CAD software shouldn’t mean “limited functionality,” says PTC. In fact, you can have both ease of use and “deep functionality.”
2. 3D CAD designs should be both robust and portable, making it easier to reuse designs by capturing information about the model as you work, and then using that information to make reuse easier. “It should simplify the process of accessing older design data with newer versions of the software,” says PTC.
3. 3D CAD software shouldn’t make changes hard to deal with, because, after all, changes are a way of life for most mold designers. “The key to avoiding wasted time is to manage change by managing your CAD data effectively. Doing this requires visibility into data file structures, and having reliable mechanisms for automating design updates,” PTC states. “Today’s powerful 3D CAD software packages give you tools for examining your data hierarchies, and let you be selective in specifying automated updates. This way, you can easily turn off all associativity, for instance, to keep a change local, and avoid updating other models.”
4. 3D CAD users should not hit a “functionality ceiling,” notes PTC. If you have to stop and go outside your application for help with analysis, manufacturing constraints, or other issues, you waste time and potentially introduce data translation errors into your work. “The ideal 3D CAD software integrates a robust geometry kernel with a complete repertoire of design and analysis applications—all accessible within the original CAD application.”
5. A 3D CAD system should be easy and cost-effective to maintain. “It should include installing new applications, upgrading to new versions, migrating to PLM systems, and even integrating with business planning and financial processes,” says PTC. “And maintenance can’t be kept a low priority, because your CAD software is directly responsible for the quality and competitive differentiation of your products.”

—Clare Goldsberry

Download the whitepaper entitled, “Five Things You Should Know About 3D CAD Software” from PTC, as well as SolidWorks’ whitepaper, “Bridging the Worlds of 2D and 3D CAD Design.”