I’m going to write this article about my homemade CNC machine for anyone interested in building their own. First, let me explain what a CNC machine is. CNC stands for Computer Numerical Control. In simple terms, a CAD (Computer-Aided Design) software generates tool paths for any design, which are then exported as G-code. This G-code is read by a CAM (Computer-Aided Manufacturing) software, like Mastercam, CamBam, or Mach4. The CAM software interprets the G-code and sends the necessary commands to the CNC driver board, which controls the movements of the CNC machine.
My CNC machine isn’t highly advanced, but it works well for my projects. I built it primarily for cutting wood, stone/marble, copper, aluminum, and iron. Unfortunately, there are some issues with backlash in the bearings, so it struggles to cut harder materials like stone, copper, and iron. However, it performs very well with wood and aluminum, and it’s also quite effective for use as a plasma cutter. In plasma cutting, there’s no physical contact or friction between the material and the plasma torch, which allows it to operate smoothly.
Now, let me describe the materials I used to build my CNC machine. The base is constructed from 0.5 x 1.5-inch rectangular iron pipes, which I joined together using a welding machine.
For the sliding mechanism, I used window sliding bearings that move along iron rods welded onto 1.5 x 3-inch rectangular iron pipes. I’m using a total of 16 bearings: 8 for the X-axis, 4 for the Y-axis, and 4 for the Z-axis. However, it’s important to note that if you decide to use the same type of bearings, you should carefully check their quality. When I first bought these bearings, there was no backlash in them, but after applying some pressure, I noticed backlash starting to develop. So, before you start building your own CNC machine, make sure to invest in high-quality bearings.
Now, how do the X, Y, and Z axes move back and forth? I’m using two 36-inch threaded rods for the X and Y axes, and one 14-inch threaded rod for the Z-axis. Each threaded rod has two nuts: one to move the arm forward and the other to pull it backward. These threaded rods are connected to stepper motors, which rotate the rods clockwise and counterclockwise to achieve precise movements.
