This one’s really janky
At some point I took up an interest in CNC type machines. Since I had a rotary tool lying around in my shed, I figured the one that I was most prepared to build was a little desktop CNC router.
I didn’t really want to spend a lot of money on this, so I tried to use mostly the cheapest materials I could find at my local hardware store. The frame was made out of 1″ steel pipe and fittings, and all the linear motion was done with acrylic sliding on aluminum u-channel sandwiched between skateboard bearings. I upgraded later to cheap 8mm linear rods on the x and z axis, but left the y axis as was. The lead screws are 1/4″ threaded rods and drove each of the axes through bolted-on coupling nuts. The plates were all made of old 1/4 in acrylic sheets or MDF, and I hand drilled all the fastener holes since I didn’t have access to a drill press. The rotary tool was strapped in with a thin piece of steel and I just eyeballed the alignment on everything until I was satisfied.
To run the machine, I used an arduino running GRBL and DRV8825 drivers for each of the 3 stepper motors. I greated GCode files on my laptop by using Fusion 360 or CamBam, and sent them to the machine using the Universal GCode Sender application.
Surprisingly, it actually worked! I used a little 1/8″ 4 flute carbide endmill to cut lots of different things out of wood and MDF (granted at low feeds and really shallow depth of cut). Here’s a brief video of it working on one of the body panels for my tricopter
Rigitidy was not really concern for me when I was building this. Obviously, trying to cut harder material or running at more agressive feeds and speeds was not really a possibility with this machine, but for what I was using it for, it did get the job done. It was a useful tool to have in the garage and I learned a lot about CAD, CAM, and CNC machining through using and improving upon this project.
