For manufacturers, model-based definition (MBD) can bring tremendous benefits as explained in the previous article “Top 5 Reasons to Use MBD.” However, adopting MBD is a significant cultural shift from the status quo. In a presentation about sharing MBD implementation experiences, Casey Gorman of Sparton pointed out that the biggest challenge of MBD implementation is not the software and not the suppliers, but the internal 2D drawing mindset or culture. Many lessons have been learned in the MBD cultural shift by manufacturers all over the world. In this article, we will share the top mistakes made in MBD implementations along with suggestions to avoid them.
One of the top mistakes is that 2D drawings are still made as the master document. An unidentified SOLIDWORKS customer once raised an inspiring question: all of the investments we have made in the past 20 years in either 2D CAD or 3D CAD have only been to make faster and better 2D drawings at the end of the day. Can we do better than that?
This company is not alone. Here is a seemingly obvious but actually complicated question: When there is a conflict between a 3D model and its 2D drawing, which one does your organization take as the master? According to a SOLIDWORKS customer survey in 2015 (sample size: 486), about two-thirds of responders indicated taking 3D models as the authority over 2D drawings. One-third indicated the opposite.
Congratulations to the first group: You have laid a very solid foundation to support MBD. This 3D-oriented culture focuses on the end goal, the products in the 3D world, rather than the common means of 2D drawings. This culture can help liberate manufacturing from the 2D drawing constraints, realizing the full potential of 3D models and streamline processes, because designs are already built into 3D models and it’s more efficient to take the original source as the authority.
To the second group, let’s revisit the scenarios where 2D drawings override 3D models and understand why. Then we’ll gradually establish 3D models as the master in several pilot cases to identify issues, solve them and cultivate a 3D-oriented culture. In Gorman’s presentation, one of the first recommendations is to take 3D models as the master. For example, if the shop floor just redlines the drawings on the fly, rather than notifying the design team to update the model, try to stop that. A previous blog post, “Don’t Rely on 2D Drawings as the Master Anymore,” shared more suggestions and examples.
Another misunderstanding is to treat MBD as the same as paperless processes. These two concepts are often mixed up in MBD discussions. Does MBD have to be paperless? No. Do paperless processes have to be MBD? No. Let’s clarify here. MBD focuses on the communication style. It’s 3D model-based, not 2D drawing-based. Figure 1 shows several MBD prints that are obviously not paperless. Paperless specifies the communication medium: It’s digital, not paper. Figure 2 shows a computer terminal in a digital factory displaying a 2D drawing. It’s paperless, but certainly not MBD.
Figure 1. Paper prints from a SOLIDWORKS MBD 3D PDF.
Figure 2. A computer terminal displaying a 2D drawing on a shop floor.
Why is this clarification important? Because some of us have been scared away from MBD by the concept of “paperless.” For example, we may not have the resources to purchase or maintain digital devices to avoid paper prints. On a greasy and dusty shop floor, or in an extremely cold field installation site where thick gloves are needed, hard copies are very robust and handy. Or some people may simply prefer reading paper documents rather than viewing digital displays.
MBD is already a major undertaking. Going paperless at the same time could be too much to take on and generate too many disruptions. So let’s take one step at a time and keep this in mind: Paperless processes are nice to have for MBD implementations but are not required, especially in the early phases. Even without the heavy upfront investment in digital devices, MBD can still go a long way and add great value in a very cost-effective fashion.
With that said, if your organization does have the resources to implement paperless processes, that’s great. It will certainly help bring MBD to a higher level. For example, Gulfstream Aerospace equipped shop floor engineers with workstations as shown in Figure 3. Gulfstream was the first to achieve a long-held aerospace industry dream: an aircraft developed with a Federal Aviation Administration–certified, fully electronic MBD system. In 2007, the company designed the G650 model entirely using the MBD approach. Later, a good portion of the G650 MBD data was reused in the G500 and G600 models so that Gulfstream was able to design these two new airplanes together and announce both test flights in early 2015. This blog post has more details.
Figure 3. Gulfstream implemented both MBD and paperless processes. (Image courtesy of Dan Ganser.)
To recap, 2D drawings generally shouldn’t be used as the master reference in MBD implementations and MBD is not the same as paperless processes. What cultural shifts are you experiencing in your MBD efforts? You’re welcome to discuss in the comment area below. To learn more about how SOLIDWORKS MBD can help you with your MBD implementations, please visit its product page.
About the Author
Oboe Wu is a SOLIDWORKS MBD product manager with 20 years of experience in engineering and software. He is an advocate of model-based enterprise (MBE) and smart manufacturing.