Last week I was task with creating two identical molds of a finger. It was a very interesting experience from which I learned a lot about how to create a mold, as well as the things to avoid.

Assignment Overview

For the project, I first decided to do a trial run with my thumb. It didn’t work out too well, so I decided to create molds of my index finger for the rest of the project. In total, I had 1 unsuccessful attempt at a thumb mold, 1 unsuccessful attempt at an index finger mold, and 2 successful attempts at a index finger mold.

The process of creating the molds was very simple, but it required quite a bit of attention to detail. The first task was for me to measure out alginate and water in a volume ratio of 4 to 1. After this, the substances were mixed and I inserted my finger in order to create a mold of it. After waiting approximately 5 minutes, I was able to remove my finger from the now solid mix, which left a very detailed mold of my finger.

 

 

 

 

 

 

 

Following this, I mixed plaster and water in about a 1.5:1 ratio (for index finger attempts) and poured it into my finger mold to create a finger cast. I was able to leave a screw in the plaster by holding it in place using a single piece of tape. I let the plaster solidify for about 3 hours, and was able to tear away the alginate/water mix to uncover my casted finger.

 

 

 

 

 

 

 

Attempt 1: Unsuccessful Thumb

My first attempt was definitely the one I learned the most from. The biggest problem was that I used incorrect ratios in both my alginate and plaster mix. This was much more noticeable in the plaster mix, as I mixed closer to a 1:1 ratio than a 1.5:1 ratio. This left my plaster very brittle, and unfortunately the thumb had crumbled before I was even able to get it out of the alginate.

Attempt 2: Unsuccessful Index Finger

The second time around, I was much more comfortable with the ratios I needed in order to have a successful mold/cast. However, with the correct ratio of plaster came much more thick consistency, and I failed to think about the possibility of air bubbles being in my cast. As a result, there were various holes in my cast where the plaster was never able to reach.

Attempt 3: Successful Index Fingers

As the saying goes, the third time was indeed the charm for me. I was finally able to both get good consistencies out of my mixes and casts without air bubbles. However, they weren’t perfect, as is seen in the photos. One seemed to have a crack around the fingertip while another had quite a noticeable gash in the same area. Nonetheless, I am very happy with how they turned out and believe them to be a success.

 

 

 

 

 

 

 

Cost Analysis

Labor:

$7.25/hour for 5 hours of work = $36.25

Material Cost:

Alginate ($15/lb – 1/5lb) = $3

Plaster ($1.50/lb – 1/5lb) = $0.30

Total: $39.55