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3D Or Not 3D? That is the Question

By Eric P. Leitner, CSP, CSM, CIM, C.Tech, OAAAS, AMIEEE

So you've heard the news for years that your industry is making the move from two dimensional flat drawings to three dimensional modeling. Is it time for your design and development team to do the same? Will there be enough benefit in making the switch to be worth the cost of the software, training and the time spent on the learning curve?

Before diving in at the deep end, you first have to consider whether or not there is an advantage in changing your current drawing methods. Often, in less complex projects, more traditional draughting methods get the job done quite adequately. Remember that not all that long ago the 2D versus 3D design decision wasn't in the realm of possibility for any of us. Only a few years before that, computer aided design and draughting (CADD) was entirely non-existent.

Somehow, we still managed to put up buildings and bridges, and get commercials products designed and out the door. A moment's reflection on the ancient Egyptians is all that is needed to realise that 3D CADD modeling methods are not a prerequisite to designing astounding structures.

However, we have come a long way since then. The tools now available to us on the market have a number of significant advantages regardless of the industry in which we operate. Both the reduced cost of this software and the less specialised expertise now required make use of it makes 3D modeling an option that is becoming increasingly attractive to design teams.

This is especially true when balanced against the advantages of 3D modeling. An architectural model created in 3D allows for automatic creation of elevations, sections, isometric and even perspective views. Mechanical assemblies can be checked for both fit and function on the screen without having to go to the building of prototypes. Civil projects can generate automated cuts and fills at regular intervals, leaving the software to do the tedious calculations.

More recently, software manufacturers have introduced various levels of intelligence to 3D modeling. Just as when you were first introduced to your own industry, before being able to discuss subject with coworkers, one first has to learn some of the jargon used in the field. The terms used by 3D modelers may at first seem complex, but can easily be understood with relatively little effort. Remember that we experience life in a 3D universe; many of the terms that seem difficult when explained in writing are intuitively understood by young toddlers.

The first concept to demystify is that of "constraining" parts or assemblies. Constraining typically means nothing more than attaching things together. Placing a coffee mug on a table constrains the bottom of the mug to be coplanar with the table top. Snapping the cap on to a pen makes the cap concentric and coplanar, also sometimes called an insert. With me so far? Rolling a ball or the wheels of a toy car across the floor implies that the surfaces are constrained as tangent. Some 3D modeling software can apply these relationships to the parts you see on the screen, allowing the designer to move parts around to see how they'll behave.

More powerful CADD packages have additional higher end capabilities built in. Software termed "parametric" allows for rule driven components. The criteria for specific parts are used to influence their physical characteristics. For example, an increased load on a floor may cause the support beams to automatically thicken if the loading is taken as a variable in the design of those beams. "Associativity" is a related capability which allows parts to adapt to the components around them, such as a clamp resizing itself to the rod on which it is attached should the rod's diameter change.

All of the above can contribute very significantly to an improved bottom line. Most obviously, if your buildings, structures, mechanical assemblies or whatever product you design is modeled in 3D, all of the associated view creations such as sections, elevations and details can be drawn by the computer in a matter of seconds rather than the hours or days currently being spent. Additionally, since these views are all being generated from the same model, they will always be accurate representations and in most cases can be set to automatically reflect any changes to the original design.

There are also some often overlooked advantages to modeling versus traditional draughting. We, as technicians or technologists, have been trained to read blueprints and engineering drawings. Our clients, however, have not. In the case of residential architecture, showing a client images of their proposed house before construction even begins ensures that they understand and approve what you are about to build. Commercially, examining a 3D model of a product on the screen has much of the same advantages. Sometimes, having a rendered image of a proposal included in a bid may make the difference between receiving a contract or chancing to lose it.

Other departments within your company are likely to also make use of images created by your 3D models. Marketing can use screen captures in promotional materials. Purchasing can be fed automatic Bill of Material (BOM) reports directly from the software, streamlining their workflow. Instructions for products requiring assembly can even be animated to a file and included with your products' supplied documentation.

You know that you've heard about some of these benefits of 3D for years. Now you have to decide if it's time for you to make the switch. If you're still undecided, try contacting some of the manufacturers of modeling software or their local sales representatives. Most are more than willing to showcase their products to you, and even provide you with free trial versions. Keep in mind that simply ordering a CD will not get you any closer to a decision than you already are now. Trail software that doesn't get removed from the cellophane package is referred to in the industry as "shelfware." Try to apply the trial period to a specific project. Better yet, have a CADD consultant or one of the software vendors model your project head-to-head against your internal design team. Base this competition not only on the time required for the design, but also on the effort required for drawing revisions.

If and when you do decide to take the plunge, remember to set aside some funds training for yourself or your staff. Just as your first introduction to CADD software was anything but instinctive, a little training during the transition will go a long way. Just don't ignore the question of 2D versus 3D; after all, you may have a strong interest in adopting the new technologies . . . before your competition does.

Eric P. Leitner is a Certified Technician (C.Tech.) in the disciplines of Building/Building Design, Computing and Electronics with OACETT, as well as an associate member of OAAAS.