Traditionally, CNC machines were limited to factory floors and run by CNC operators. But with the introduction of desktop CNCs like the Bantam Tools Desktop CNC Milling Machine and the Bantam Tools Desktop PCB Milling Machine, engineers, product designers, educators, and even people who have never even heard of CNC machining before can now machine their designs into reality in their lab, classroom, or home workshop.
Meanwhile, in this guide, we cover:
- Defining 3-axis CNC machining
- 3D printers vs. CNC machines
- Laser cutters vs. CNC machines
CNC involves precisely coded instructions that are sent to a microprocessor in the control system of a machining tool that allow for a high level of accuracy and consistency. Today, when people talk about CNC machining, they almost always mean a machine connected to a computer.
One way CNC machines are classified is by the number of axes they have. The Bantam Tools Desktop PCB Milling Machine and the Bantam Tools Desktop CNC Milling Machine are 3-axis CNC machines, meaning it allows simultaneously controlled movements along the X, Y, and Z-axis.
In a 3-axis machine:
- The Z carriage moves up and down
- The X carriage moves from side to side
- The Y carriage moves from front to back
Note: The Bantam Tools Desktop CNC Milling Machine is 4th axis compatible.
Each of these carriages is driven by a stepper motor. These stepper motors drive each axis in precise movements or “steps.” These motors can appear in different places depending on the CNC machine you’re using.
Note: Be careful to avoid knocking these boxes because this can cause accuracy issues.
There are also 2-axis, 4-axis, and 5-axis machines. Knowing the number of axes your CNC machine has is crucial when it comes to designing parts, how you’ll set up your part, and more.
For example, when designing each of our getting started projects, we had to keep in mind that the end mill (a tool used to cut material) would only be able to mill the top of the stock because the tool holder is part of the Z carriage, which moves up and down. Understanding this helped inform the designs we created, the toolpaths we programmed, and the fixturing we used.
3D Printing vs. CNC Machining
Our Bantam Tools Milling Machines and Bantam Tools Milling Machine Software often get compared to 3D printers. Like a CNC machine, a 3D printer relies on a design file and computer-controlled commands. However, whereas CNC machining is subtractive (carving away parts from a piece of material), 3D printing is additive (adding layers to create the desired object). Most desktop 3D printers fabricate parts using plastic filament (usually either PLA or ABS), building one layer at a time.
There are pros and cons to each of these digital fabrication methods, and the one you choose depends on the type of part you're looking to make. As a result, many engineers, machinists, artists, and product designers use a combination of CNC machining and 3D printing to fabricate prototypes and manufacture parts. One of the key benefits of having a Bantam Tools Milling Machine is the variety of materials you can mill. Rather than being confined to plastic, you’ll be able to make functional prototypes because the machine is optimized for aluminum.
Laser Cutting vs. CNC Machining
Like our Bantam Tools Milling Machines, a laser cutter is a form of subtractive manufacturing that relies on computer-controlled commands. With a laser cutter, you create a design, load it into machine-control software that can read the file, and then the software sends instructions to the laser cutter to cut a 2D shape. A similar process happens when using Bantam Tools Milling Machines and the Bantam Tools Milling Machine Software. However, a huge benefit to using a digital fabrication tool like our Bantam Tools Desktop CNC Milling Machine is that it’s a 3-axis CNC machine. The three axes can move simultaneously to machine 2D, 2.5D, and 3D parts.
If you’ve used a laser cutter previously, you’ll love our built-in SVG support. With our SVG support, you can drop in designs to machine 2D and 2.5D parts without having to dive into CAD/CAM software. See our SVG Workflows guide for more information.
If you’d like to dive deeper into the evolution of CNC machining, check out our “History of CNC Machining” series on Bantam Tools CNC Life: