Modular DIY CNC Machine

(For a more in depth instruction, view my Instructable: Modular DIY CNC Machine)​

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I wanted to build this CNC machine as a proof of concept while at the same time create something I could upgrade in the future. I used Inventor to create my design until I found something that would optimize my build area while also fixing issues with my previous iterations. The area of travel for the cutting tool is 8" in the X, 14" in the Y and 2" in the Z, but this could be increased if longer aluminum extrusions were used.

The work piece itself is fixed on the wasteboard below the machine. In my first version the work piece actually moved and the gantry was stationary, however I found multiple issues with this design. The gantry moves along the Y-axis via belt drive with motors on either side of the frame. The X-axis moves perpendicular to the Y-axis along the gantry, also via belt drive. Attached to the X-axis is the Z-axis, which moves up and down via screw drive. The overall design is similar to the X-Carve mixed with the Open Builds Acro laser cutting system.

Again, the goal of the machine is to allow it to be upgraded later on. This means the extrusions can be scaled up or down to fit your needs and budget. I've also designed the Z-axis to have a basic attachment scheme, meaning multiple tools can be attached so long as an adapter is designed with matching mounting holes. For my purpose,

The overall cost of this machine ends up being around $325, not including a Dremel or Laser. I hope you find this Instructable useful if you decide to build your own CNC. There are a lot of resources out there for doing so, and I hope I've created something that helps centralize a small portion of this information.

Tools Needed
One of the main goals for this project was to create the CNC machine by using the least amount of tools possible. This does increase the cost in some places, however the majority of the tools needed are pretty basic or readily available. Here's what I used:

1. Drill
2. Allen wrench
3. 3D Printer (can also have custom pieces printed via 3D Printing services)
4. Hot glue gun
5. Tap and die set

Parts Prep
A few parts will need to be prepared in order to fully fit for the machine.

• The small bracket holes are slightly too small for the 0.25" cap screws, so you'll have to increase the size using a drill until the hardware fits. In hindsight, it might have been best to purchase the recommended bracket hardware from 80/20 but I was trying to save some money.
• All 3D printed parts should be cleaned of all supports. Some holes may need to be enlarged/test fit to make for easy assembly later on.
• The wasteboard will need to be prepared since it shows where the frame will attach later on. Use the attached template to drill the mount holes for the leg braces, along with the holes for workpiece clamps. I ended up tapping these holes using the 8mm threaded rod once they were drilled. Another option is to use inserts or the spare hex nuts, although this would increase cost/time required.
• Make sure the ends are tapped for all Aluminum extrusions except for the 1010 x 16" ones.

Y-Axis Slide Assembly
Reference the Instructable



X/Z-Axis Slide Assembly
Reference the Instructable



Gantry Assembly
Reference the Instructable



Final Assembly
Reference the Instructable



Electronics Routing
Reference the Instructable




For other tips/references on electronics and running the machine, view my Instructable: Modular DIY CNC Machine