Now that I’ve got a pretty good handle on all things laser cutting (and now that the laser cutter is becoming obstructively popular), I have been pining for a CNC machine capable of processing full (4′ x 8′) sheets of plywood. Since a CNC of that scale is well beyond my means at the moment, I gave myself permission to become a member at the local MakerPlace and took my last of a three class series on Tuesday. I spent my Saturday applying what I’ve learned and I can safely say I now know CNC. Sure, that may not be as exciting as Neo’s proclamation “I know kung fu!”, but I am very proud of it.
The basic steps are described below:
Everything depends on a vector graphics file. This part I already knew from laser cutting. Here is what I had going in. I used adobe illustrator but I could just as easily have exported geometry from 3D CAD software.
Using proprietary Computer-Aided-Manufacturing (CAM) software, I learned to apply actual motions and relationships of cutting tools to the digital geometry. This was the most difficult part as I had to learn about how things are manufactured, different types of cutting tools, how to determine spindle speed, and a whole bunch of other manufacturing trivia. I also had to learn the big differences between laser cutting and a cnc router. There is an actual spinning tool that adds danger, kerf, and an inability to cut inside corners.
Operating the Machine
This part was pretty straight forward (but a bit scary). I learned some basic procedure then was given the keys to the kingdom. This is what the process looks like.
Here is the first and much improved second thing I made. Still lots to learn but it’s a good start.