Hello Everyone!
Today I will be walking you through how I made my finger plaster. Using a scale, I measured out 33g of alginate and 1:2 parts of water. This made sure that my mold was not too watery or clumpy. On my first attempt, I mixed the mixture too much, and it started to harden before I was able to put my finger in, resulting in a clumpy mold. My second attempt was a lot smoother with almost no clumps.
After creating a smooth mold mixture, I transferred the liquid into a smaller container and stuck my finger in it for 5 minutes for it to harden. Once I felt resistance from the mold itself, I was able to take my finger out and pour my plaster in. My plaster mixture was created by putting together 1:1 ratio of plaster to water. I poured my mixture into my mold and placed the nail and 3d printed part to hold my finger once it dried.
Measuring my mold
Plaster powder
Shown below is a picture of my set up. I waited 24 hours for my plaster finger to dry, and then I went back to the OEDK to pull my finger out. For some reason, my finger broke each time I tried to pull my finger out. I concluded that it was not dry enough and I had poured in too much water into the mixture in the first place. I attempted a total of 3 times before I could finally figure out the correct mixture and the appropriate timing. Some improvements I made along my journey are: waiting more than 24 hours for my plaster to dry and mixing in less water into the plaster especially with the humid Houston weather, where things don’t dry as quickly. Both of these improvements combined allowed me to successfully pull out my finger on my 4th attempt.
After pulling out my first finger, I was able to create another plaster mixture with a better sense of how much water to add. I came back in 36 hours this time and pulled out another perfect finger. Here are my 2 fingers pre-processed!
After pulling out my fingers, I was able to sand off the parts that were not smooth and spray paint them in order to post process. I picked the color red because I thought it would be funny to have fingers that had the color of blood. I spray painted 3 layers with 20 minutes of drying time in between. Here is the final product!
From this project, I learned that there was a lot of trial and error process that had to be done in order to have the correct concentration of alginate and plaster mixtures. The drying process also depended on the amount of time and the surrounding humidity, which also made this curing part a little bit more difficult. Next time, I will be sure to use the correct ratio and let it dry completely before pulling my fingers out to prevent fractures. Here is a picture of my clean work space after I was finished.
Cost Analysis:
- Alginate: $ / Ounce * 1 Ounce = $0.78 (amazon)
- Plaster: $1.99/lb * 1lb = $1.99 (michaels)
- Labor: $15/hour * 3 = $45
- Red Spray Paint: $5.98 * 1 = $5.98 (amazon)
