Introduction

For this assignment, we were tasked with using the CNC machine to create a 2D negative on a piece of wood. I had never used the CNC before, so I was looking forward to learning the software and best practices.

Step 1: Choosing a Design 

I used the Noun Project and used this link to download the file. Looking forward to Easter, I chose an Alpha and Omega cutout that I thought was neat.

Step 2: CNCing

I attended the CNC tutorial, which was very edifying. By the end of it, I had carved out one of my two CNC parts. The machine was a lot easier to use than I initially thought it would be. I uploaded the file into the carving software and specified the two depths I wanted each outline to have. Then, I made a curved, rectangular outline for the logo, which I set to cut all the way through. I then secured my piece of wood into the machine using the metal clamp and calibrated it. I used a 1/8th inch drill bit and the smaller of the two CNC machines to make my cutouts. The part took under thirty minutes to cut. I then had to repeat this process two more times because one of my cuts failed. I set the cut depth too low, and the base of the drill bit hit the wood, which caused it to eat into the logo itself. The pieces came out pretty nice, however, it definitely needed some sanding and coloring.

  ///    /// 

Calibration^^                                                         ^^After the CNC finished^^

Step 3: Post Processing

To start post processing, I used the orbital sander on all sides of the cutout. This removed the random stray lines and pigments on the wood. I wanted to add a stain to highlight the bright, polished look of the wood. However, the only stain left was white, and it looked really ugly when applied to the wood. So, I then spray painted both blocks blue and let them sit out to dry. I made the mistake, however, of drying paint against a paper towel, which left remanence behind when I pulled it off. I managed to scrub most of it off with a wet paper towel and incessant finger scrubbing. I then painted the lettering with black paint to make it stand out better.

      ///   

Post-sanding ^^                                                spray-painted and painted wood^^

My final thoughts…

I can see how the CNC can be a powerful tool to create complicated geometry (within reason) that would otherwise take a regular person many days to whittle or cut out. I initially didn’t like how they came out, but seeing it again, I like how the spray paint makes a nice background for the lettering. I look forward to using it for my final project, and how there aren’t any unforeseen problems with it (clear foreshadowing…).

<–Clean work space

Cost Analysis

Wood: $6.81 per 6 ft; 16″ of 1×4 wood ($1.51)

Wood Stain: 1/12 of a can at $19.99 per can ($1.67)

Spray Paint: $5.98

Labor: $15 per hour for 4hrs ($60)

Total: $69.19