A compact enclosed CNC router built for milling custom PCBs.
Because sometimes waiting for PCB shipping is boring.
Prism CNC is a compact, enclosed desktop CNC router designed specifically for PCB milling and small precision work.
It’s built mostly from repurposed Ender 3 components, custom sheet metal plates, and aluminum extrusion. The goal was to create a rigid, fully enclosed machine that’s small enough to live on a desk but powerful enough to mill circuit boards and small parts reliably.
300mm+ Work Area Because tiny CNCs are sad CNCs.
Fully Enclosed Frame Acrylic panels + sheet metal walls keep chips contained and make it look cool.
Ender 3 Hardware Reuse Extrusions and motion components salvaged from broken printers.
775 Spindle Motor Cheap and capable for PCB milling.
Linear Rails For smoother motion and better rigidity than ender 3d printer-style wheels.
Limit Switches So the machine can actually zero itself instead of guessing.
Electronics Bay Dedicated compartment for the controller, motor driver, and power supply.
The frame is primarily built from both 20x20 and 40x40 aluminum extrusion, reinforced with custom sheet metal plates that tie the structure together.
Side walls use a layered approach:
- 3D printed supports
- Acrylic panels (for diffusion + aesthetics)
- Sheet metal structural plates
This keeps the machine rigid while also making it look less like a pile of metal beams.
The machine uses a 775 DC motor as the spindle. It’s not industrial, but it’s perfect for:
- PCB milling
- engraving
- light cutting operations
And most importantly: it’s cheap and easy to replace.
The electronics live in a rear-mounted box that houses the CNC controller and spindle motor driver. The power supply for the CNC is mounted on the rear side wall.
Keeping everything in one compartment helps keep wiring more manageable and protects the electronics from debris.
I realized something after getting my first 3D printer:
Having fabrication tools at home massively speeds up projects.
Prism CNC is meant to expand that capability by bringing PCB manufacturing and precision milling into the same workflow.
- Automatic tool probe
- Better spindle
- Dust extraction
- PCB auto-leveling
Or I’ll get distracted and build something completely different.
Ideas, improvements, or chaos are welcome.
Open an issue, submit a PR, or just tell me what you would improve.
The CAD is open source, and you can find it here!
The wiring is a bit self explanatory but you can also follow this:
All the fun bits you need to make this yourself live here!
Note: This design assumes you have two spare Ender 3 printers to supply items such as the motors, aluminum extrusions, and power supplies. If you dont already have some scrap printers, you will need to be sure you get these extra components!
This project is 100% open-source and powered mostly by questionable engineering decisions.
If it breaks, turns a copper board into modern art, or makes a rainbow
that’s on you.
