Ellena CNC Capybara | ENGI 210: Prototyping and Fabrication

Hi everyone!

Today I will go through how I created the Capybara with the CNC machine.

The process:

First, I downloaded the Capybara Icon from the Noun Project. I downloaded the file as svg because that is the type of file that the CNC machines can take. From there, I used Carbide Create to modify the file. I first measured the wood block’s size with a caliper. It was 5.5 x 3.5 x 0.75, so I modified the stock size and thickness to correspond my measurements. I first adjusted the size of the element so that the minimum distance would be 3 inches as that is what the assignment said to do. The height of the capybara was adjusted to 3 inches. Then, I set the offset distance to 0.25 in and offset direction to inside and added tabs to the design. The tabs would help the piece stay in place instead of cutting all the way and flying off. Then, I created the tool paths for the outside dimension of the shape. I added a vector cut tool path and a pocket cut tool path for the detail on the capybara. The red line on the image below is the vector cut and the blue is the pocket cut! I simulated the file to visualize what would happen and double check that everything was correct and then sent the file to myself so I could access it from the CNC computers.

After setting up my file and double checking my simulation one more time, I exported the file as G-Code and then opened Carbide Motion. From Carbide Motion, I was able to import my file and start initializing the machine. To initialize, I needed to zero the machine. To do this, I put the BitZero on the corner of the wood block and taped it so that it would not move when the machine was zeroing the machine. This step allows the machine to find the x, y, and z zero of the system to initialize the cut. The machine would move its drill inside the BitZero’s circle and every time it hits the side, the light turns red because it conducts electricity.

After initializing the machine, I was able to cut on the Nomad! During the cut, I had to stop the machine several times to vacuum sawdust because the Nomad does not have a vacuum. The second image is a picture of the finished Nomad piece. It did not cut all the way through, and this process is described later on.

Nomad Cut Piece Before Post-Processing

After starting nomad machine, I was able to start the Shapeoko machine. The Shapeoko was a little bit different in that I had to clamp the piece down in the machine using the green pieces (pictured below). I exported the G-Code again and initialized the machine similarly. Because this machine does have a vacuum, I didn’t have to pause and vacuum periodically.

Clamped Capybara

After finishing with the CNC machining, I got 2 blocks with the capybara still attached to the wood block. Both machines did not cut fully through the block and there was a very thin film that connected everything still. To resolve this issue, I used an orbital sander to gently smoothen out the piece overall and sand off this thin layer. I was left with the tabs still, which I used my hands to detach from the wood block. I pushed the pieces away from me so that it would not damage my pieces. After this, I sanded the pieces down both with sandpaper and the orbital sander. After reaching the smoothness I wanted, I used the bees wax to coat the pieces and post process the pieces. I did 2 layers of waxing, and then I was able to get the color that I wanted.