A challenging aspect about the 3D realm is being able to visualize and properly understand different perspectives before bringing an idea to life. For this homework assignment, I was tasked with using CNC machining to cut out a noun from a block of material.

Ideating

I began the assignment by brainstorming different ideas to CNC. I wanted something that could be used to hold something rather than just be placed somewhere for display. For this reason, I settled on the idea of a coaster with a small decoration on the inside. At this point, I had never used or even seen a CNC machine before, so the entire process seemed very overwhelming and intimidating.

Carbide Create and CNC

When it came to determining the contour and pocket, I chose to create pocket for the inner portion of the coaster and create a contour around the text. However, after completing the CNC, I realized that I did not consider the order of these steps nor the depth causing the final printed piece to remove the text component as it created the pocket. Looking at the final component, I also noticed that the coaster was much thicker than I had wanted and while I could have modified the measurements in Carbide, I instead decided to print something else.

I then experimented with Carbide and decided to create puzzle pieces after some inspiration on Google. I created a simple circular puzzle and carefully assigned measurements of where I wanted the CNC to create the contours and the pockets. However, once again, I did not consider the offset causing my puzzle pieces to not fit together. While I was a little disappointed, I decided to go with a simple design one final time.

At this point, I had used the CNC machine multiple times and using it for the final project (for the chess piece) made me much more comfortable with using the machine. For my final try, I decided to get a picture of a bowl of fruits from Noun Project. Using a caliper, I carefully set the measurements for the design as I wanted and continued to CNC.

Once it was complete, I noticed that the depth that I had set for the contour was not enough and that I should have created much more depth. Nevertheless, I decided to continue and finished printing out the second identical piece.

Epoxy is not Paint

After the two identical pieces were printed, I sanded the pieces starting with a 250 grit sanding paper and going all the way to 800 grit to get a nice, smooth finish. During the sanding process, I accidentally chipped away one of the borders within the design (due to the low depth I had set the design to).

Initially, I had decided to spray paint my final pieces. However, since the depth of the design was not appropriate, it was not quite obvious what the design represented. For this reason, I decided to forgo spray painting, and planned to paint the pieces using acrylic paint. Unfortunately, the OEDK did not have acrylic paint or any sort of watercolor paint forcing me to look for another alternative. As I searched in the back for the possibility of finding some type of paint, I found epoxy and decided to give it a try. Again, like the CNC machine, I had never used Epoxy before so I did not know that it would be really different from paint.

For the Epoxy, I poured some of clear liquid from the syringe into a cup and placed 1-2 drops of the color I wanted into it and mixed it. After creating a uniform liquid, I used a popsicle stick to place the liquid within the thin edges of the design. I noticed that epoxy was quite thick and that my edges of the design were really thin. To adjust for this, I changed from using a popsicle stick to a thin straw to spread the color into the carving within the wood. This eventually ended up being really messy. While I wanted to stop and forgo the idea of using Epoxy, I realized that I was almost done painting one CNC piece and that I would have to do the same to the other to make them identical. For this reason, I continued and tried to use Epoxy as carefully as I could.

After Epoxy, I sanded the CNC pieces once again to remove any excess epoxy that smeared on the side.

Setbacks are Learning Opportunities in Disguise

At the end, I was definitely not happy with how my pieces turned out. If I were to repeat the process again, I would be even more careful and meticulous about setting the measurements on Carbide before using the CNC. Secondly, I would make a better choice for post-processing. Despite the setbacks, I am really glad that I became familiar and comfortable with using the CNC machine. I even got to experiment with Epoxy which is something I would not have learned about if I had not used it. Looking back at my first blog post, I had mentioned that I wanted to learn to use the CNC and that is something that I can definitely check off my list. In retrospect, while this assignment was not successful in terms of its physical aspect, there were many learning opportunities in the backend that I experienced and will carry over to my future projects.

CNC Piece Cost Analysis

Below, I have provided a breakdown of the cost estimate for my CNC piece.

Material Cost:

• Wood [1]: $17.19/4 pieces X 2 pieces = $8.60
• Clear Epoxy [2]: $4.60
• Color Dye [3]: $4.75

It is assumed that CNC machine can be rented at facilities like the MakerBarn [4]: $40/730 hours X 24 hours = $1.32 (assuming machines are rented for 1 day).

Overall Material Cost: $19.27

Labor Time:

• Planning on Carbide Create: 2 hours
• CNC: 1.25 hours
• Post-processing: 25 minutes
• Epoxy: 40 minutes

Total Labor Time: 4.53 hours

Overall Labor Cost [5]: $7.25/hr X 4.53 hours = $32.84

TOTAL CNC PIECES COST: $52.11

[1] https://www.walmart.com/ip/4-Pack-Unfinished-Wood-Blocks-Panel-Boards-for-Crafts-Painting-Pyrography-4x8-inches/597321296

[2] https://www.amazon.com/PC-Products-70147-PC-Clear-Adhesive/dp/B008DZ19WC/ref=sr_1_10?keywords=epoxy+glue&qid=1670907942&s=industrial&sr=1-10

[3] https://www.amazon.com/Spice-Supreme-Assorted-Colors-Yellow/dp/B00GNHIBZU/ref=sr_1_6?keywords=food+dye&qid=1670895014&sr=8-6

[4] https://www.themakerbarn.org/memberships/

[5]: https://www.minimum-wage.org/texas#:~:text=The%20Texas%20minimum%20wage%20was,Federal%20Minimum%20Wage%20by%20reference