Building a CNC router from scratch
A pictographic account of my high school senior project
At my high school, senior was required to do a senior project to graduate. The project was intended to encourage students to try something that might give them a sense of direction for their career. Some kids worked fixed up cars, others job shadowed and wrote reports, and I built a CNC router. Building a CNC router from scratch is an ambitious undertaking for a high school student. Luckily I had help. My dad wanted to have a CNC router for his shop, so he convinced me to take on the project, and supported me by bank-rolling the project and donating his time to build it with me.
Phase one involved building a base on wheels to house all the electronics for the machine. Wheels were a requirement - my dad likes to be able to move equipment around in his shop to save space when things aren’t in use.
The designs were purchased based on this Fine Line Automation kit. We didn’t buy the whole kit though from FLA, only the motion components: motors, bearings, lead screws, flex couplers. Being adventurous and trying to save money, we bought the aluminum extrusions for the frame on eBay in random lots as they were available.
Since the extrusions weren’t ordered to length, I had to cut all the pieces to length, drill holes at all the joints, and tap the holes to fit fasteners.
After the frame was completed, it was mounted to the stand and bolted in place securely. Then I proceeded to wire the whole thing. The stand itself has an AC junction box inside it, where the computer and motor drives connect. Each axis motor runs on four wires which connect to the drive in the stand. Limit switches at the end of each direction of travel prevent the router from breaking itself should it move to far in one direction. The router itself is powered directly by AC which is not controlled by the rest of the system. All of these wires run through the cable tracks and connect in the bottom of the stand.
Of course, this machine wouldn’t be useful without a user interface. It didn’t have to be fancy, it just needed to work. Money was saved by using an old monitor and mouse and keyboard I had laying around. To protect the operator from flying debris when the machine is running, a plexiglas shield was installed between the monitor and the router.
