CAD at home: Common now, groundbreaking over 10 years ago | #TBT

Enter the Matrix

To get started, you need the proper software for the job. Some CAD programs may be too expensive for the average enthusiast, but there are freeware options available as well—yes, we said free.

Most home computers can run CAD software. Even ancient PCs with low-end graphics cards can run the simpler CAD programs now available. However, running certain tests requires a bit of computing power to crunch through all that data. 

The engineering industry has generally catered to Windows-based computers, but software for Mac operating systems is available as well—although those programs could be considered scarce. And for those tech nerds out there, you can even find some programs for the Linux-based operating system.

Once you’ve selected a computer and software suite, you must learn how to craft shapes in a three-dimensional virtual world. This is tough work, as you really have to understand how the software functions. However, completing some basic tutorials is the fast track to familiarity.

Though the learning curve is steep, there are numerous benefits to mastering CAD software. At the top of the list is the fact that it’s the single easiest way to create and design in 3D space. For example, a roll cage can be completely designed, pipe by pipe, in the virtual world. Imagine the headaches you’d avoid by being able to see a finished cage before cutting a single piece of tubing. 

Using the same CAD software, you can then print out two-dimensional drawings of each piece of the cage. The drawings will provide the correct lengths, angles and notches, and they’ll even tell you exactly how many feet of tubing you’ll need to purchase for the job. This information will undoubtedly save time and money, as it removes the stage of trial and error altogether.

CAD design isn’t limited to metal parts, either. It can be used for projects constructed out of wood, fiberglass, plastics and more. It’s also not limited to machine design, as this software works well for mapping out electrical circuits and wire harnesses. The possibilities are vast.

Optimization Prime

CAD software can be used to create any part you can dream up, even complex assemblies like transmissions and differentials. Some software offers an animation feature that allows you to see the part in motion, and numerous tests can be run once the part has been constructed in virtual space.

While usually reserved for the more expensive software suites, tests such as finite element analysis or computational fluid dynamics flow analyzers are incredibly useful tools that can be used to maximize the performance of a car. 

Finite element analysis is a very complicated method of simulating stress on parts in the virtual world. For example, you can stress test a roll cage created in CAD software by applying a virtual force to it and seeing what areas of the design are the weakest. Data from a simulated crash could reveal the problem areas of a poor design, allowing for critical improvements before welding has even begun.

Computational fluid dynamics flow analysis, on the other hand, simulates the movement of fluids like air and water around a shape or body. This gives the designer the ability to visualize airflow around a car or a wing element, and it can be a huge advantage for the enthusiast who doesn’t have access to a wind tunnel. 

CFD analysis can also model how air passes through an engine. You can design an intake manifold and observe the airflow before you even touch a piece of aluminum.

I Am Iron Man

While enthusiasts can definitely use CAD to create part renderings, few have the ability to machine the parts at home. Other options exist, though, like outsourcing the work to online services or even the shop just around the corner. Many modern machine shops have the equipment to CNC mill, lathe, laser cut, water jet cut or even rapid prototype parts from CAD plans. 

That said, it’s certainly possible to create a design that’s impossible to machine. Tooling paths for machine bits must be considered when designing complex shapes. Otherwise, you could end up with something that can’t exist given the constraints of current fabrication technology. However, a decent understanding of the manufacturing process and communication with your machine shop should help you avoid these problems.

Use the Force

Despite its relative accessibility, today’s CAD software can help you produce some serious works of engineering. Don’t just daydream about that cool splitter, wing, shifter or gauge panel you’ve been turning over in your mind. Even structural pieces like roll cages and suspension components are within your reach with the help of CAD software. 

Just think of CAD as another tool in your toolbox. And as with any other tool, using it appropriately will help you find success.