Making the finger hooks for this project was my first experience with molding and casting! I was surprised by how straightforward the process was. First, I mixed alginate with water in a 1:4 ratio by measuring the amounts in grams using a scale for about 4 minutes. Then I placed my first finger inside the mixture and waited for about 5 minutes for the mold to harden, slowly pulling out my finger after the shape was fixed. I then mixed plaster with water in roughly a 2:1 ratio and poured it into the mold. Lastly, I used tape to fixate the screw with its head inside the plaster and left it to solidify for about an hour. I repeated this process to make another finger hook.
When the fingers were finished, I found that the screw placement was not very ideal, since they stuck out a little at the top. I think it was because I placed the screws a little too deep inside the plaster, so I redid the plaster and screws using the same original molds I made with my fingers the first time.
The second batch of fingers turned out better since the screw placement was a little better. I think it could possibly be a little more straight in aligning with the axis of the fingers, but that depends on preference and I don’t mind the slanted look of the finger hooks.
Finally, I spray painted the hooks with a clear coat enamel spray to protect the surfaces.
Done!
Cost Analysis:
Raw materials:
- alginate ~ (80 g)*($8.99/453.6 g) = $1.59
- plaster ~ (40 g)*($22.78/11339.8 g) = $0.08
- water ~ free = $0
- screws ~ 2*($10.97/184 screws) = $0.12
- clear coat enamel spray ~ $6.98
Labor, machine, overhead:
- labor: ~ 3 hr ($7.25/hr) = $21.75
Total:
$30.52
