In this article I’ll continue to focus on direct modeling programs. These programs address the needs of woodworkers who produce custom products. They offer a completely new method of producing shop drawings. That is, they allow your draftsman to create a model of your product before you begin to cut wood. A model created in this manner can be clearly understood by clients, workers, and CAM programs.
In order to make this process work efficiently, it’s important to choose the right program to meet your needs. Unless you’re well versed in 3D modeling, choosing the right program can be a challenge. In order to help with this process, I’ve compiled a list of program functionality that needs to be assessed when considering the purchase of 3D modeling software for custom work.
What are the important aspects of program functionality we need to consider?
The first consideration is how efficiently you can create accurate models. Efficiency in modeling requires a lot more from the program than meets the eye. Virtually any program will allow you to create an extruded rectangle within seconds. This solid can be used for any rectilinear part such as the side panel in a cabinet. But when it comes to adding features and building assemblies for wood products, some programs are more efficient than others. For example, how readily can you create a series of holes for adjustable shelves based on your specifications? Can you readily create a cope-and-stick relationship between parts?
While you’re building a model, you need to be able to verify that the model is accurate. To achieve this, you need to be able to clearly visualize your model. Complete visualization is challenging because you’re dealing with a 2-D view of 3-D objects. Manipulating your point of view allows you to simulate 3-D viewing. A “3-D mouse” is a great help in manipulating views of objects. Check to see if the program you’re considering supports this type of device. Once you can visualize your model from all angles, you can verify dimensions and model integrity. That is, as long as the program has the right measuring tools. It’s generally not feasible to place dimensions on parts as you build since it tends to clutter the screen.
Another important consideration is how well the program handles modifying an assembly once it’s created. This ability is used over and over again in woodworking. Modifications are necessary due to mistakes, clients changing their mind, or field conditions evolving. Modification is also important because it allows you to build your library by using an existing assembly to create a new one. Some programs allow you to “stretch” an assembly with all parts updating appropriately in one step, as can be done in drafting programs. Others require you to modify each part separately and then re-fit the parts correctly. This might not seem like such a big deal until you consider repeating the process a few hundred times.
Comprehensive modeling programs allow you to save views of your model in separate windows where you can dimension and perform other drafting functions. Some programs have this layout function within the same file as the model while others use a separate file linked to the model. Each method has its advantages.
Other Aspects to Consider
Although the following aspects of modeling programs are not the core issues, they’re still important to consider.
- The cost of the program. While this may be an obstacle for some, it shouldn’t be the deciding factor. Think about the hours that the program will be used over the next year, for example, and how much even a ten percent increase in efficiency will save you. The same holds true for maintenance costs.
- The learning curve. The more functionality a program has, the longer it takes to learn. When you consider the long term, the investment is well worth the effort. A program can be quick and easy to learn but may lack certain functions that could potentially save a lot of time in day-to-day usage. On the other hand, some programs are easier to learn because they’re more intuitive. You can learn a program faster if the interface seems familiar. Programs that run in Windows, for example, should comply with Windows-style menus and dialog boxes.
- Technical support. This is most important when learning the program or when a program is updated. Good technical support indicates that the program creator is looking for a long term relationship with users and is willing to shoulder the cost of making sure it’s working for them.
- Import/export functionality. In order to get the greatest benefit from modeling programs, it’s important to be able integrate with other programs. Fortunately, most programs will allow you to translate through several common formats. Just make sure you can work with the entities after they’re imported. The geometry usually comes through fine but other entities such as dimensions may not be usable after being translated. Surface textures may not translate at all. Plan accordingly. When working with vendors, don’t be concerned about complying with what some call “the industry standard”. Just be sure your program can translate to a format that your vendors can use.
- Programs that run inside other programs. Be wary of these. First of all, you have the cost of purchasing and maintaining two programs. Also, you take on the potential incompatibility and bugs of two programs when upgrading and it’s often hard to discern wherein the problem lies. Consider what the real benefits are of having one program run inside another before purchasing.
I hope these aspects of program functionality help you in finding the right 3D modeling program. In my next article, I’ll take you through a typical purchase scenario. We’ll explore techniques for testing functionality and we’ll expose some of the potential pitfalls.