In fact, the demand for 2D CAD is significant enough that publishers best known for 3D CAD, such as Dassault Systèmes, have introduced their own flavors of 2D CAD. In 2010, Dassault Systèmes released DraftSight, a 2D CAD application with which any ACAD user will feel right at home.

In hindsight, I should have realized that 2D CAD would have some sticking power. After all, at the time I made my prediction of the impending demise of 2D CAD, drafting boards were still in general use.

For trivia buffs, the patent for the first drafting table as we know it was awarded to George Ring on July 18, 1905 (U.S. patent 795,065). How many people do you know that still use a drafting board? There may be one or two diehards for whom mechanical drafting continues as an art form.

The first modern drafting board.

Why does 2D CAD persist? Early on, from the mid-1990s to the early 2000s when 3D CAD was still new to people, many viewed it with skepticism, perhaps as a passing phase. By around 2005, most of my students were still 2D CAD users. Many students in the early days (1998 to around 2005) only interacted with a computer to use ACAD or to play a game of Tetris or Solitaire. Windows was a mystery to them, and I often found myself teaching both SOLIDWORKS and Windows.

One student told me over lunch on the first day of 3D CAD training that he would leave design rather than learn a new CAD program. That could have been an indication that 2D CAD would stay around because of the reluctance to change in what might be called mid- to late adopters—except that most of them have aged out of the workforce. The people who are currently using 2D CAD today are younger and computer savvy. They often have experience with other design packages, so hesitancy to change is not a problem.

Cost is one factor in 2D CAD’s lingering popularity. Generally, 2D CAD costs less than 3D CAD, and the hardware required for 2D CAD is generally less expensive. For many companies, such as a small machine shop that just needs to sketch up a prismatic shape every once in a while, an inexpensive 2D CAD program running on an inexpensive PC is sufficient.

That being said, smart companies know that the cost of software and hardware is far less than the costs of the greatest assets—their employees. They know that the intrinsic efficiencies of 3D CAD far outweigh the additional costs. Smart companies also realize that when there is little advantage to 3D CAD, like the small machine shop with simple prismatic parts, the costs of purchasing 3D CAD will be hard to justify—not to mention the costs of retraining employees and the learning curve of mastering 3D design.

Careful evaluation of the return on investment (ROI) in migrating to 3D can also keep 2D CAD around. A hybrid 2D/3D environment may be the best solution. A company that has been around for a while has likely accumulated a large amount of 2D CAD drawings, which will provide reason enough to keep 2D CAD.  

In some cases, 2D drawings of designs are rarely referenced or changed. Since 2D drawings can be of complex assemblies and remodeling in 3D would take a considerable time and effort, it may be deemed more expedient to edit the 2D CAD for the few times that changes are needed.

A legacy 2D CAD drawing.

Many companies have a bounty of physical drawings and may need to get these drawings into a digital format. While it is easy enough to scan a paper drawing to 2D CAD, getting a 3D model is more of a manual process. And if scanning is not an option, then it’s back to the drawing board—figuratively speaking.

Legacy does explain all of the reasons for 2D CAD still being around, but this accounts for only a fraction of the amount of 2D CAD being used. For certain disciplines, 2D is still a better tool.

Take civil engineering, for example. Civil engineers use layouts and elevations in the form of 2D drawings. Creating 3D models of the surrounding landscape, road elevations and gradients may not be worth the effort when 2D drawings can convey the same information.

2D civil engineering layout drawing.

However, 3D CAD is gaining traction in civil engineering, particularly in the design of structures such as buildings, dams and bridges. In additional to their better visualization, 3D models lend themselves to simulation. It's hard to imagine that many of today's amazing structures could have been built without the ability to simulate how these structures will react to forces generated by wind, seismic activity, heat, cold and a variety of conditions these structures must endure.

The use of 3D models for evaluating wind effects.

Plants are laid out with floor plans and elevation drawings. Simple shapes, such as rectangles, are sufficient to represent equipment and the area they will occupy. For large plant layouts, detailed 3D CAD models may be counterproductive because of the complexity of the model and the strain they will place on the computers that have to store and display them.

A 2D plant layout drawing.

Schematics are another area where 2D CAD rules. Whether it be electrical, PCB, hydraulic or pneumatic, schematics can easily be most efficiently represented by simple symbols, 2D routes and a series of tables.

PCB schematic.

However, there is 3D CAD software, such as SOLIDWORKS Electrical 3D and SOLIDWORKS Routing, that can help automate the process of generating these systems. A 3D model can be invaluable when routing piping, as shown below.

3D pipe routing.

For those who have evaluated their needs and concluded that 2D CAD is the right solution, there are many products to choose from. Dassault Systèmes' DraftSight is one.

Dassault Systèmes began to offer two versions of DraftSight around 2010: a fully functional, free 2D CAD version and a pro version that added AutoLISP support and access to technical support.

DraftSight is available in several flavors that provide solutions for the varying needs of individuals and organizations. For those who are familiar with AutoCAD, DraftSight offers a similar look and feel. It has the same command line, and there is a coordinate system that ACAD users are familiar with. Granted, there are some differences, but most ACAD users should be able to grasp these differences quickly.

The variety of bundles is one of the strongest selling points of DraftSight. This diversity allows individuals or organizations to pay for what they need. The bundles include DraftSight Professional, which costs $249 for a 12-month subscription, and DraftSight Premium, which costs $599 per year as of the time of this writing. DraftSight also comes in Enterprise and Enterprise Plus versions. Enterprise versions  are geared towards organizations that have large 2D CAD departments. For these organizations, the Enterprise offerings can be more cost-efficient than purchasing individual Professional or Premium licenses.

DraftSight bundles.

A detailed feature comparison of the different DraftSight offerings is available from this link.

In hindsight, my proclamation of the death of 2D CAD was, in the words of Mark Twain, greatly exaggerated. Although 3D CAD has replaced traditional 2D CAD in many fields, as seen in this article, 2D CAD remains useful and is healthy and strong. Therefore, I revise my prediction to one that believes 2D CAD will be alive and useful for some time, between the next generation and forever.

About the Author

Joe Medeiros is an Elite Applications Consultant at TRIMECH, a premier SOLIDWORKS reseller servicing customers throughout North America, and offers SOLIDWORKS customers expertise in implementing and using Dassault SOLIDWORKS solutions.

Joe has been involved in many aspects of the Dassault SOLIDWORKS product family since 1996, and as an award-winning blogger, he regularly writes about Dassault SOLIDWORKS solutions.

Lions and mammoths encounter one another in a painting in Chauvet Cave, France. The painting was made between 28,000 and 30,000 years ago.

Drawings have been a staple of planning and recording since prehistory. In caves across the world, humans began drawing by marking their interaction with nature across the walls of their fire-lit homes. As human technology progressed, so did our ability to illustrate ideas.

Fast forwarding through the eons, drawing took on many forms. Perspective was first honed by the Greeks, the Romans brought precision to the drafting table and the Middle Ages brought skewed perspectives with oblique visual descriptions of cities, castles and wars. Though drafting would progress, it wasn’t until the Renaissance that technical drawing came into its own. Working in Florence, Italy, a designer named Filippo Brunelleschi ushered in a new theory of drawing that contemporary people would understand as a blueprint. Using linear perspective, the Italian began constructing some of the most wonderful architectural feats that world had ever seen. To guide their construction, Filippo used his diagrams and, in doing so, introduced the world to technical drawings.

Since their invention, technical drawings have evolved. In the late 18th century, Gaspard Monge, a French mathematician, developed his ideas of descriptive geometry, codifying the planar views that manufacturers are familiar with today. In the middle of the 20th century, another seismic development occurred in technical drawing. Geometric dimensioning and tolerancing (GD&T) was created to make manufactured goods more consistent with their technical specifications by more precisely defining required precision and allowable variability.

Most recently, the technical drawing’s path has merged with another transcendent technology—the computer. Since the mid-1970s, technical drawing has moved off of the drafting table and onto the computer screen. Today, designers use CAD to create 2D drawings, 3D models and animations that describe how parts should be made. With CAD, technical drawings have become easier to create and share. However, engineers have started to realize that CAD drawings aren’t necessarily the best way to distribute, correct or archive manufacturing documents. Instead of relying on drawings, engineers have started to look for ways to combine the models they’re creating with the technical drawings that were based on those 2D and 3D forms. This new phase of technical drafting has been called model-based definition (MBD).

What Is MBD?

MBD is essentially a term that describes a 3D model that contains all of the annotation data that would be needed for a part to be manufactured. Aside from dimensions, an MBD model will communicate a component’s GD&T requirements, material information, configuration details, and other data that could be useful for anyone that might have input into the manufacturing of a design.

An MBD 3D model. (Image courtesy of Quality Digest.)

Who’s Using MBD?

As of now, MBD is still a nascent technical drawing paradigm. However, industrial catalysts like the U.S. Department of Defense (DoD), select companies in the aerospace industry and the automotive sector have started to insist that any vendors working on affiliated projects have to produce 3D MBD models.

One of the biggest factors driving this trend is the lifespan that some DoD and aerospace products see before they’re eventually retired. For the DoD or Boeing, having a machine run for 20, 30 or even 50 years isn’t out of the ordinary. With service lives that stretch out that long, its easy to see that building design information directly into a model can be invaluable. Who’s to say that the designer of a particular system on a legacy aircraft will be around to impart his or her design intent to the younger engineers deputizing the design work when something goes wrong down the road?

Another benefit that MBD offers engineers is the ability to use their models as a verification datum upon which they can automate inspection of manufactured parts. With all of its dimension and definitions built right into the model, MBD components can be used in conjunction with coordinate measuring machines and 3D scanners to ensure that a part meets documented manufacturing standards without having to reference outside drawings. All of the information that would be needed to compare the two parts would be right there attached to the model, making an often painstaking and time-consuming process much easier and quicker, while also enabling more process automation.

Aside from its communication and validation benefits, MBD has also been able to deliver cost-savings to those who have adopted the emerging documentation trend. Since adopting MBD principles, Toyota, Boeing and BAE have demonstrated up to a 50 percent reduction in costs in the product development processes. What’s more, the Naval Air Warfare Center Aircraft Division based in Lakehurst, N.J., has noted that after implementing MBD into its design workflow, the cost of labor used in component fabrication has dropped 30 percent.

Why Adopt MBD?

In the end, MBD is valuable because it preserves the geometry of a 3D model while still delivering all of its manufacturing information that’s usually associated with a 2D technical drawing. Because MBD relies on 3D geometry, it gives manufacturers or anyone interacting with a 3D model greater insight into the design intent of each feature as well as a more natural way to interact with a virtual part. Though that might seem simplistic in its promise, machinists who have to transform raw stock into goods could really benefit from visualizing a part in 3D before deciding on CAM setups and toolpaths.

Furthermore, design teams working across time zones could use MBD models to better understand their colleagues’ design requirements without having to sift through reams of paper drawings and manually searching for minute bits of information.

Finally, as we’ve seen, drawings have been evolving ever since man wanted to communicate an idea down through the ages. While MBD, with its 3D nature and its intrinsic link to computers, might seem completely disconnected from the cave paintings of old, when you take a step back, you notice that both techniques are trying to do the same thing—communicate an idea in the most sophisticated and enduring way possible so that good ideas find fewer ways to be lost.

If MBD is going to be the next evolution in drawing’s long history, the age-old trade could have done worse. With its ability to condense information into an encyclopedic form, MBD appears to be an excellent way forward for technical drawing.

About the Author

Kyle Maxey is a mechanical designer and writer from Austin, TX. He earned a degree in Film at Bard College and has since studied Mechanical and Architectural drafting at Austin Community College. As a designer Kyle has had vast experience with CAD software and rapid prototyping. One day he dreams of becoming a toy designer.