There just isn’t enough time to spend on training? A typical excuse.
By Walter Silva
There was a time, not so many years ago, when a designer or engineer was hired based on technical expertise in a given area (like four-slide mechanisms or die design) and how well they appeared to fit into the department dynamic.
Nowadays, one of the major requirements in most job ads is, “Needs to be proficient in XYZ CAD.” When I was a young engineer, I never saw a job ad that required expertise with an XYZ drawing board. It was just assumed that if you were an engineer or designer you could find your way around a drafting board and a mechanical drawing.
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The problem doesn’t stop there. For the past 14 years I have spent a tremendous amount of time training both new and experienced engineers and designers in the use of mechanical CAD systems and I can tell you from experience that more than half of all CAD users are sadly deficient when it comes to using their favorite application.
You should be able to whip out just about any design that your mind imagines as fast as you can relay it to a colleague in a meeting. If you constantly waste time looking for functions or experimenting with how to use them, you are definitely a member of this group.
What many users fail to appreciate is that CAD modeling requires more than just a mastery of an area of technical knowledge. It also requires the honing of mechanical skills. A concert pianist studies theory of music, and the mechanics of melodies and chordal variations. The artistry of the performance comes from thousands of hours of tedious practice, developing hand, eye, and brain coordination to make every arpeggio and chordal progression flawless. CAD modeling requires that same level of practice.
Running Out Of Time
Most CAD users acquire a rudimentary knowledge of their particular application and then proceed to muddle through one design job after another. The typical excuse is that “There just isn’t enough time to spend on training.”
In many cases, experienced users will point out that they went to a training course when they first started using the application. (Of course, that was 20 years ago and in the ensuing years two dozen releases of the software have come and gone; there are a thousand new functions that didn’t exist when they had training, and they slept through half of that class anyway.) Even when an aspiring user comes to class, they often fail to follow up after the training with additional practice, thus attenuating the full benefits that could have been realized from the experience.
Practice Makes Perfect
To master CAD modeling, you have to practice, practice, practice. If you are serious about knowing your application, you should attend training classes throughout your professional career, not just when you first purchase the software. To complement quality training, the best way to hone your modeling skills is to build as many models as you can. It is especially important to venture outside of the area that you normally live in. If you do a lot of sheet metal design, spend time making models of plastic parts and machined parts. If you work mostly in plastic, jump across the fence and try some sheet metal. By venturing into design areas that you normally avoid, you will come across tools and functions that will come in handy in unusual design situations.
Every time you create a CAD model you reinforce the use of the tools used in the construction. I tell my students that you want to master your application to the point in which your fingers can do the CAD so that your mind can go back to working on the design aspects of the problem! Playing with the CAD system also gives you a chance to experiment.
When you are working on a real job with a looming deadline, human nature dictates that you will not take any chances that might sabotage the project. When you are doing the same, safe thing it is really difficult to acquire new knowledge. Playing with a non-important model is a completely different ball of wax. You can experiment with new tools, slicing and dicing your model as you learn new tricks. If you mess things up, it really doesn’t matter. You can just blow that puppy out of the water and start again.
As you develop greater familiarity with the CAD system of your choice, you will also want to master many of the shortcuts, hot keys and customizations that streamline the use of the software. I am constantly amazed by the number of users who use software “out-of-the-box” without ever taking advantage of the shortcuts that power users live for. My favorite gripe is the user (often a seasoned veteran), who complains about the amount of effort it takes to do something as he drills through one drop-down menu after another to select standard functions that most users access with a hot key.
So assuming that you get the message and want to turn over a new design leaf, is there a best way to master solid modeling? Here’s my Recipe for Becoming a CAD Master:
- You must commit to investing a substantial amount of time to really master an application. If you weigh the investment against the returns, however, you will find that it definitely makes sense.
- Start by investing in a good training class and/or one or more top-notch training manuals. Modern CAD systems are extremely rich applications, and while you can eventually pick up many of the techniques on your own, it is much more productive to have an experienced instructor quickly guide you to the critical information that you need to know.
- Follow up the initial instruction with constant practice. There are many approaches to mastering solid modeling but they all share this common denominator. Practice. Practice. Practice.
- I like to organize modeling instruction by progressing through the modeling of types of parts. I start with class one parts that are basic extrusions of simple profiles. Once you master that, there are thousands of class one parts that you can make.
- Now, concentrate on class two parts that are basically combinations of two or three basic extrusions.
- Next, work on simple revolved parts, made from simple profiles revolved around a single axis.
- Follow up with manifold parts, like pipe tees and valve bodies, that involve positioning multiple extrusions in three-dimensional space and then shelling out the final mass to create the manifold.
- The next order of complexity is the creation of simple plastic parts with draft that are shelled to a uniform wall thickness.
- Creation of sheet metal parts is the next logical step.
- More complex plastic parts with intricate internal ribs and bosses follow on the agenda.
- Cast parts with complex intersections and blends are the next challenge.
- Finally, integration of advanced surfaces into hybrid surface-solid models brings you to the pinnacle of CAD modeling achievement. Even if you rarely need to make models this complex, learning how to create them has some real benefits. Once you’ve created a complex part with multiple NURBS surfaces, you’ll never again panic when faced with the construction of a basic mechanical part!
In summary, the secret to mastering solid modeling is to practice. Even the world’s most famous concert pianists practice on a regular basis. You would do well to emulate them.
Walter Silva, president of CPD Inc., is a veteran mechanical engineer with more than 39 years of industry experience in plastic part design, molds, and fixtures and machinery development. Silva is the author of the well-known series of Doctor Walt’s books that cover CAD software, rapid prototyping and technical desktop publishing, as well as the co-author of 11 multimedia training CD-ROMs. He is also president of Pro Cad Inc. For more information, visit www.docwalt.com.