Cadalyst - October 2008 - (Page 40)

mcadmodeling Figure 3. If you don’t constrain everything in your sketches, changes in the model will cause the unconstrained items to move unpredictably. Figure 2. When the tolerances in two 3D CAD applications don’t quite agree, you can end up with imported models that have wideopen gaps. Some 3D modelers have tools to heal them. system recognizes a dimension as 1.000, and the second sees 0.9997. These two numbers are essentially the same in the real world, but they aren’t the same to a computer. When tolerances don’t agree, you end up with geometry issues. What originally was a watertight model comes into your 3D modeler with gaps, overlapping edges, or both (figure 2). You have no choice but to fix these problems. Time is money, and fixing problems of this nature can consume a lot of both. So What Do We Do? You’re probably thinking, “How do we minimize these issues?” You have several choices. First, take a little time to observe which techniques you use to create your models. If you use a parametric modeler, make sure every sketch is fully defined before you proceed (figure 3). I can’t tell you how often I have examined a problematic model only to discover that the sketches had all sorts of undefined geometry. It’s not going to work, folks. If you don’t tie everything down, changes will bring unexpected results. If there’s no time to do it right, where will you find the time to do it over? Another way to avoid problems is to establish good corporate modeling standards. Some of you are cringing, but you really need them. (For more information about standards, see my August “MCAD Modeling” column, “Do You Need Modeling Standards?”) If you establish good practices and adhere to them, at the very least you’ll know what to expect when you open your coworkers’ files. Fully parameterize your models, put features on designated layers, label everything you can (figure 4), and so forth. Establish some basic modeling standards and you’ll limit your potential problems greatly. A really good way to minimize modeling surprises is to be kind to your coworkers. You’re a team, so you all should have the same goals. Working well together increases efficiency. Mutual cooperation and teamwork minimize egos. When people aren’t feeling territorial about their modeling 40 Figure 4. Whether they are for layers or individual features, descriptions impart intelligence. The more intelligence you build into a model, the easier it will be to work with. habits, they will begin to open their minds to new or different ways of doing things. If the company benefits, you benefit. So, if you learn to do something, share that knowledge with as many others as possible. If someone is having a problem, help out. You’ll find these good deeds will come back to you in the future. Also, it looks good on your annual review if you can say you helped those around you. Work It Out No matter what, you’re going to have occasional problems when you use other people’s models. And any time you translate something, you invite trouble. But if you take a little time and expend a little effort, you can pare down those problems to a minimum. Mike Hudspeth, IDSA, is an industrial designer, artist, and author based in St. Louis, Missouri. www.cadalyst.com cadalyst October 2008 http://www.cadalyst.com

Table of Contents Feed for the Digital Edition of Cadalyst - October 2008

Cadalyst - October 2008 Contents Editor’s Window Cad Central SimCity for Real Designs Spring to Life — 3D Publishing Tools Make File Sharing as Easy as Opening a Book Xi MTower 2P64X — Dual Quad-Core Workstation ArchiCAD 12 — BIM Software Dell Precision M6300 — High-End Mobile Workstation Cad Manager Mcad Modeling Aec Insight Cad Cartoon Issue Indexes Hot Tip Harry

Cadalyst - October 2008

For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.