Be a Renaissance Modeler (MCAD Modeling Column)1 Jul, 2007 By: IDSA ,Mike Hudspeth
Explore all the possibilities to become a better designer.
Two of my favorite quotes came from Walt Disney's The Black Hole. Hotshot pilot Charlie Pizer quips to cutesy robot V.I.N.CENT., "All work and no play makes Jack a dull boy," to which Vincent replies, "All sunshine makes a desert, say the Arabs."
What has that got to do with 3D modeling, you ask? Plenty! One of my pet peeves is dealing with people who model as if the only tool they know is a hammer. Everything looks like a nail to them. They know one set of techniques and stick with them for everything they do. They never branch out and try new things. They have an entire toolbox at their disposal but let most tools sit rusting as unused icons in virtual disuse.
Know Your Toolbox
I would venture to say that if you have 3D modeling software, you have a GUI (graphical user interface, figure 1). It's the current state of the art in how to get things done on a computer. I would add that as you look at the screen, you'll find little icons and pull-down menus. And most of those items expand to reveal even more icons and choices. They each have a purpose.
Figure 1. Virtually every 3D modeling program on the market today uses a GUI to organize and present its available functions.
Do you work on your own car? Maybe you're handy around the house. You should think of your software as you do your toolbox. You open the box, the little tray pulls out, and you have all kinds of different tools that do different things at your disposal.
I had a pointy-haired boss once who insisted that I create engineering drawings using Microsoft Word. He was more familiar with Word, and someone along the way had shown him that it had some minor drawing functionality. We struggled and fought with it for months (really—months!) before getting the kind of results he wanted. Every time we told him it couldn't be done, he refused to believe us. He just knew we could do it. What a man of faith he was! We ended up using our 3D CAD package to create a parametric sketch of the product family (a cardboard box!) that we could change at will and saving a graphic for each version. The long and short of the story was that although Word could do what he wanted, it wasn't designed for what he wanted it to do. It wasn't the right tool for the job. And what happens when you try to use the wrong tools? You waste time and money building your model and even more time and money when you—or more often someone else—has to edit it. It's a lose–lose situation.
Figure 2. When figuring a right triangle, the formula you use changes depending on what information you have. It's the same with modeling: The tool you use changes depending on what you know and what you want to establish.
Most software products have at least three ways to do just about anything you want to do. Explore all of them. Find out why there are so many ways of doing essentially the same thing. If you look closely enough you'll discover that although the end result may look the same, the information you need and the procedure you have at your disposal can be vastly different.
Figure 3. To model this part, just sketch the path and give it a thickness.
When you figure a right triangle, you change which formula you use because of the information you have (figure 2). It's the same with deciding which command to use. Depending on what you want to accomplish, you'll undoubtedly find that you can use more than one of those tools to tailor your model to the results you want. Use the right tool for the job.
Figure 4. You can also model the same part by sketching the path and a cross-section and then sweeping the cross-section along the path.
Let me give you an example. Let's say you want to model a solid macaroni shape. UGS NX has a command called Tube that can create a curve or set of curves that depict the center of the path you want your model to occupy. All you need do is select the curve(s) and give the outer diameter (and inner if necessary), and the model will pop into existence (figure 3). Alternatively, in addition to the path, you also can sketch the cross-section and sweep it along the path (figure 4). Then again, you can extrude your shape and add radii to the corners (figure 5). Of course, you can create this model in other ways, but I think you get the point. There are many ways to model, and no one is always going to be the best. Which one you choose will depend on what you want to do with the resultant model and how much down-the-road flexibility you want it to have.
Figure 5. You can achieve the same model by sketching the silhouette of the object and extruding it. Of course, you'll have to radius all four corners.
When you explore the tools in your virtual toolbox, you'll want to make good use of your software's Help documentation. I know that's a scary subject; some software's Help isn't very helpful. But the more you or your company paid for that software, the more help should be available. Find it and use it.
You can usually find Help under the Help pull-down menu. Typically, this type is installed with the software. Sometimes software companies leave it on the installation media because it's so big. But if you're like me, you like a printed manual. It's just nice to be able to lay it on the desk and refer to it as you go.
Another kind of help that is popular is context-sensitive help, which is available from within a command. It will bring up subjects and suggestions relevant to the current command. It can be handy when you don't really know what to ask.
When you go to your Help menu, you will find out where your help lies. Either the software will ask for the help media or it will take you right to it. If it's on your computer, it will come right up. Some software will take you out to the Internet. Software companies do that because they can keep their help files up to date instan-taneously and with the lowest expense. It's a bummer, however, if you are out in the field and don't have an Internet connection.
The number one suggestion I give to those who ask me how to learn 3D modeling is to play with the software. Now when I say that, I really mean play with it. I don't mean jump into the next project you get or grab an old drawing or part and try to duplicate it. In fact, I don't recommend modeling anything that is work related. Do you want to learn what you are capable of and what the software can do? Do something fun!
We all have hobbies, and chances are something for which you have a passion can be expressed in a 3D model. Model it. Pick something that you care about and make it as detailed as you can. For me, I like science fiction. I model movie props and spaceships (figure 6). They have very unusual shapes and lots of detail. They are nearly perfect for learning your tool set. For some of you it might be custom furniture or musical instruments. Even if it's a creatively shaped jewelry box, it will be sufficient to learn and practice your modeling.
Figure 6. Model something you have a passion for. If you like old cars, model one. If you're like me, try modeling something out of this world. Whatever it is, model something that you care about.
Learn and Grow
At the very least, you want to broaden your horizons. The more tools you know, the better modeler you will be. Don't let yourself get stuck in a rut. It's up to you. Explore your tools and find out what they can do for you. You will make yourself more valuable and have some fun doing it!