If you’ve done some research into product design or physical product development, you may have heard of CAD. Alternatively, you might have seen videos of engineers at computers manipulating 3D graphical representations of their work. What are these engineers doing? And what makes it an important part of product development?
CAD, short for Computer Aided Design, describes a design process or workflow which is assisted by software. Commercial CAD programs are developed for different design disciplines and applications, including structures/architecture (AutoCAD), electrical systems (Catia), and mechanical design (SolidWorks). Though some CAD programs are made to be cheap and intuitive, the most powerful programs (and the programs recognized by industry) are sold to be licensed commercially and require a high degree of training to be used effectively.
A lot of product owners think that the primary purpose of CAD modeling is to visualize their product pre-production. This is a nice ancillary benefit of CAD, but the true purpose is much more crucial. CAD modeling is used to hash out technical details without spending money on defective prototypes.
For example, imagine if you knew that your product had to fit within specified volume- say a six-inch cube. Furthermore, you know the exact dimensions of the components that need to fit in the space. If your product consisted of two, simple components, you could probably tell whether they fit in the space based on intuition. Four or five rectilinear and components and you might have to do some quick addition to be sure. Add more components with increasingly complex geometry and this becomes a tricky requirement to validate without expensive prototyping. This is the kind of problem that a CAD model can easily solve.
3D CAD modeling can tell you whether your screws bottom out or aren’t long enough to engage their threads. It can show you how far a wheel drops into a rectangular cutout. It can calculate the exact weight of a part or assembly based on the volume and the material selections. In sum, CAD modeling gives product owners the confidence they need in their design to invest in prototypes.
Furthermore, CAD files store troves of data about your product in a unified and accessible way. Part numbers, design changes, tolerances, and more. Once created, CAD files replace any pre-existing sketches or design files as the definitive reference for a product.
Perhaps most importantly, CAD files are used to generate production files- including production drawings and machine files. When it comes to 3D printing, CAD files are used almost directly as instruction for the printer. For flat processes like laser cutting, CAD files are used to create flat patterns. The 3D models themselves can also be used as a starting point for mold designs, CAD programs are capable of generating negative mold geometry from a part file. And for more complex machining processes, CAD programs generate 2D production drawings with dimensions and tolerances.
Though it’s a powerful tool and critical step in product design, CAD modeling is overlooked by a lot of engineers in training. In my formal university engineering education, I had one semester-long CAD course, once a week, at 6pm in the evening. My classmates and I learned the basics of creating geometry and generating drawings, but our skills were utterly lacking for real-world design work. Unfortunately many designers and engineers, even in the product design space, don’t go beyond this level of depth.
Fortunately, I took time outside of formal education to train and eventually became a Certified SolidWorks Professional in Mechanical Design (CSWP-D). In the process, I learned about the myriad features built into commercial CAD programs for generating industry-recognized production files and learned to model with extreme efficiency. This is the level of proficiency that my team and I bring to our product development projects at Emergnt.
