No Products in the Cart
CNC stands for Computer Numerical Control, and this describes a machine that is controlled by a computer based on a coordinate system. As discussed in some of our other articles, there are a lot of different types of CNC machines out there—from 3D printers to milling machines or routers, laser cutters and engravers, and more. While there are some fundamental differences across these CNC machines, they all require designs to manufacture and also instructions on how to carry out manufacturing in order to achieve success.
And that's where CAD and CAM come in. CAD stands for Computer-Aided Design, and this is where you might create the designs you're looking to manufacture. CAM stands for Computer-Aided Manufacturing, and this is where you would then choose key settings and parameters to manufacture your designs successfully based on your available resources.
But there's a bit more to it than that, as there is a wide range of both CAD and CAM programs available. As we will discuss, these different options can be selected to suit the needs of different types of projects and also the different types of materials and machines you might find yourself working with.
As mentioned, Computer-Aided Design software—or simply CAD for short—is a place where we can design our ideas. CAD software often has tools for drawing, modeling, adding dimensions or curves, and annotating or even sharing our designs with our peers.
These tools reflect how all products used to be made; by hand. You will often find that CAD software has digital design tools called "sketch" or "dimension", which reflect the days of creating technical drawings through drafting techniques which remained the dominant approach until the 80's when CAD software began to really take off.
CAD software comes in many different forms, with some programs designed to create two-dimensional designs like sketches, logos, or outline profiles. Meanwhile, other CAD programs might be more well-suited for modeling 3D shapes through parametric or direct-modeling approaches. And then there are specialized CAD programs intended only for a single type of design, such as software used for designing printed circuit boards (PCBs) or other programs intended for manipulating photographs.
The first factors in choosing the right CAD program for you are often your available resources. What type of computer do you have? What type of machine are you working with? And what's your budget? Let's take a closer look at each of these factors.
In today's modern age, few CAD programs are still only available for Windows or Mac, as universal software packages are more common. But if you find yourself working with a tablet, Chromebook, or a Linux device, that may reduce the number of options you have available. There are plenty of CAD programs out there, and many come in web-based or app formats.
As mentioned previously, some CAD programs like Adobe Illustrator or Inkscape are intended for making 2D designs, while others like Tinkercad or Onshape are more well-suited for making 3D models. CNC machines like 3D printers need a 3D design to work correctly, while lasers typically require 2D designs. As such, you might find that the type of machine you're working with dictates the type of CAD program you need to choose. But then again, CNC milling machines like the Carvera and Carvera Air can work with either 2D or 3D designs, offering a bit more flexibility in your design approach.
And then in regard to your budget, you may find that many modern CAD solutions are free for hobby or educational use but require expensive subscriptions for commercial or industry use. But there are still many great free CAD programs out there for a wide range of users—from beginners to more advanced users too—if you do your research.
Another factor to consider is support. Learning CAD can be a challenge, so find a CAD program that has a lot of tutorial videos and example projects for you to follow as you get going.
Once you've decided on the type of CAD program that will suit your needs, your machine, and your budget, you need to consider the type of file that will be created for the next step—manufacturing. All CAD programs will have their own internal saving structure, of course, but to bring your designs into CAM we typically export them in a more generic file format.
For 2D designs, a vector file format like .SVG or .DXF typically works well to support this type of design, as vector files carry information about each line, shape, and curve in your design, which can be easily selected and manipulated. In some cases, image files such as .JPG or .BMP can also be used, like when engraving a picture using a laser or when creating a lithophane with a 3D printer.
For 3D designs, a .STEP file is not only a generic file format that can be interpreted by different CAM programs, but it's also a file type that will allow you to continue to interact with the geometries of your design. When compared to a more generic 3D file type like a .STL, .STEP files offer a bit more flexibility for CNC milling applications specifically.
But 3D mesh files like .STL are still very useful file types and ones that are commonly used for 3D printing or when machining 3D reliefs. As a result, you may first need to choose a CAM program in order to determine what file type is best for your needs.
As mentioned, Computer-Aided Manufacturing software—or simply CAM for short—is a program that can be used to prepare your CAD designs for manufacturing. A handful of CAM programs include basic CAD tools, like Makera CAM's ability to create simple 2D and 3D shapes. And some CAD programs are also CAM programs, like Autodesk Fusion or Solidworks. However typical CAM programs only allow you to manipulate your CAD designs through basic transformations like position, rotation, and scaling.
CAM software is often less generic than CAD, as many machines will provide a unique CAM program made by the manufacturer. An example of this is 3D printing slicers, as many 3D printer manufacturers often offer their own slicer CAM programs used for preparing 3D models with their machines. But of course, there are also generic slicers that work with a lot of different brands, such as Cura or Prusaslicer.
This is a bit less common with other types of CNC machines like mills, routers, and lathes, as generic CAM programs like VCarve, MasterCAM, and Autodesk Fusion can work with a range of brands and types of CNC machines. In cases like the Carvera and Carvera Air desktop CNCs, you have the option of using these generic CAM programs or using a CAM program made by the manufacturer, such as Makera CAM.
We've mentioned that CAM software is a place to prepare your designs for manufacturing, but what does that actually mean? In some cases, it might first mean scaling or rotating your design to suit the needs of your machine or material before processing the design for manufacturing.
With 3D printers, we use CAM slicers to "slice" our 3D models into layers, which is what instructs the 3D printer on how to manufacture our design layer by layer through an additive manufacturing technique. We also might adjust the print settings for the material we're using, as some 3D printer materials need to print at hotter temperatures than others. Additionally, we can use our slicers to tune the print speeds, the print quality, the part infill density, and virtually everything else we might want to adjust to produce our part.
Other CNC machines require CAM for similar reasons but with a few different steps. For milling machines like the Carvera and Carvera Air, we use CAM to create tool paths. This is done by selecting parts of our design, like a hole, and then using CAM software to choose how that hole should be cut through a subtractive manufacturing technique. This is often done by selecting the part in the design, like a hole, then selecting the tool we're going to use, like a drill bit, and finally selecting how fast we want the drill bit to travel to create the hole we chose earlier.
We call these parameters Speeds and Feeds as they set how quickly a CNC performs these tool path operations. Speed and Feed settings often come down to the type of machine you're using, the type of cutting tool you're using, and most importantly the type of material you're working with. For example, soft materials like plastic can be machined at a much faster speed than metals like aluminum or steel.
While this can sometimes be an overwhelming task for beginners to figure out, many CAM programs help users set these parameters by recommending tools and cutting speeds based on the tool paths being created. As with choosing a CAD program for your projects, you should also always choose a CAM program that offers tutorials, guides, and examples to help you get started.
Like with CAD software, CAM programs typically have an internal structure for saving files. But this format isn't what we often export and send to our machines for manufacturing.
CNC machines operate using a coded file that instructs the machine how to move and perform the steps needed to manufacture your design based on the coordinate system we mentioned earlier. This coded file is typically written in G-Code, a programming language that can still be written by hand. But as a typical part might require thousands of lines of code to be manufactured, it's fortunate that CAM software is around to generate these code files for us!
G-Code is very generic though, with common G, M, and S commands being shared across a wide range of CNC machine models, manufacturers, and types. However, every manufacturer of CNC machines typically has their own parameters and settings needed for a G-Code file to run properly on their machines. As such, it is important to ensure you're using the correct profiles specific to your CNC machine whenever preparing your designs for manufacturing in CAM.
We're often asked, "Do I need CAD or CAM to do this project?" ...And the answer is often both! But there are plenty of places to find ready-made models and designs across the web, allowing you to skip the design stages and the need for CAD. However, we must always prepare our designs for manufacturing using CAM based on the needs of our projects and resources before starting to manufacture our project successfully.
In today's world, makers are spoiled for choice with so many different CAD and CAM solutions available, but not every program is as easy to learn as another or as versatile as another. Do your research, and make sure you choose a program that fits your style, your needs, and your available resources! To learn more about CNC machines and the software needed to use them, check out our Getting Started video series.
