Taking CAD step by step

Walking students through a course in a CAD system, a professor at De Anza College offers insights to working designers as well.

You remember school days, don’t you? The smell of chalk, the feel of new notebooks, and the click of drafters and engineers at their mouse buttons. At least, that’s how it sounds at De Anza College in Cupertino, CA. The college has a 112-acre campus and 61 buildings to hold its roughly 24,000 students. A business and computer systems lab houses the school’s manufacturing and design technology courses.

“The design courses here are a serious commitment for students,” says Louis Gary Lamit, an instructor at De Anza. Lamit’s computer-aided design courses at the college consist of 24 4-hour classes spread over 12 weeks. Enrollment averages about 20 students per section. Lamit says, “Half of my students have undergraduate or graduate engineering degrees. Three-quarters of them have worked for five years or more in drafting, design, or engineering.”

Lamit is the author of 25 textbooks on design topics including industrial modeling, engineering graphics, and CAD software. Recently, he taught a course in IX Design, part of the IX Speed suite of product development software from ImpactXoft. For this course, his students used an online textbook he wrote about IX Design. One of the chapters focused on designing a molded plastic glass washer for commercial dishwashing. “The object of the assignment was to teach the student particular skills,” Lamit says, “and to demonstrate those skills on a real-world application.” (See “Test-driving IX Design.”)

The software is based in part on a new technology called Functional Modeling, which includes features with a built-in intelligence that predefines how design elements function in the overall design—that is, how they relate to one another and behave in response to design changes. With it, CAD software automatically creates complex geometry and associative relationships between part features.

“Functional Modeling frees the designer from the problems and model failures caused by history dependence,” Lamit says. “It’s a more flexible design tool than parametric CAD. I have taught drafting for 32 years, 20 of them at De Anza. This software is one of the easiest modeling tools to teach—or to learn—that I have ever seen.”

In addition to the glass washer, other real-world designs in his class include a television remote control and a handheld vacuum. In other CAD classes, such complex projects generally result in a number of model failures and glitches. But in this class, all of the students completed every assignment successfully. According to Lamit, the textbook and the lectures certainly contributed to that, but so did the simplicity of the software.

His students concur. “Several of IX Design’s functions are helpful for molded part design,” says Gary Mahany, a veteran drafter and CAD user who took Lamit’s course. “My personal favorite was the rounds. This system can propagate rounds inside or outside of a body, cutting design time in half. Also, the rib function creates robust ribs with far fewer regeneration errors from geometry changes than rib models in history-based CAD.”

Lamit says, “People come back from industry to take CAD courses so that they can get a taste of what’s out there—to explore innovative software and design applications risk-free, away from the pressures of cost cutting and deadlines. On that level, the class gave them everything they wanted and more.”