This week in EDES 210, I molded and casted two models of my index finger. To create the first mold, I used alginate, a cheap and disposible mold material. I created a mixture of 6.75 oz of water and 1.5 oz of alginate and mixed thoroughly in a cup, then inserted my finger into the mixture and let it solidify. Once I took my finger out of the mixture, I had a successful mold of my index finger!

Figure 1: Finger Mold

Since I wanted to create two copies of my index finger, I made a second mold following the same steps as above, then began the casting process with both molds at once. I mixed 20 g of water with 70 g of rockite to create enough rockite mixture for two molds, and stirred thoroughly before pouring it into the molds. I immediately used a jig to hold a screw in place inside of both of my casts so that it would be solidified in the model.

Figure 2: Jig Setup

I allowed the rockite mixture to set for 24 hours before pulling it out of the mold. The result was two crisp, detailed models of my finger. Unfortunately, they look sad and gray right out of the mold, so some post processing was definitely necessary.

Figure 3: Unprocessed finger models

Finally, I applied a nice coat of purple spray paint to the fingers to make it look nice, carefully applying an even coat to the models without making a mess. I used a cardboard box to ensure spray paint didn’t get anywhere it wasn’t supposed to.

Figure 4: Spray Painting

I have to say I’m very happy with the outcome! The finger models are insanely accurate to my index finger, it’s almost creepy.

Figure 5: Finished Finger

Figure 6: Finished Finger

Cost analysis:

Materials:

3 oz alginate -> 24 oz = $12 at Hobby Lobby -> 3/24*$12 = $1.5

70 g rockite – > 450 g = $5 at Ace Hardware -> 70/450*$5 = $0.77

Machine Time/Tools:

I used a drill from the OEDK for stirring, but I will treat this as negligible cost.

Work Time:

2:30 hours of working time * $10/hr = $25

Total Cost = $27.27

Overall this was a very cheap project! I believe one of the main focuses of this unit was to show us how accessible molding and casting is, and I can’t believe how simple the process actually is. This was a very enjoyable project.

Figure 7: Clean Cup

*Cleaning the cup was pretty rough, there was a lot of debris from before I even used it. I was able to clean all of the gunk off from my project, but there were some turquoise bits that were pretty stubborn, not sure where those came from!