Purple fingers! During this homework assignment, I worked towards practicing my molding and casting skills by casting my own fingers and creating plaster wall art/hooks out of them. The process taught me many things about conditions needed to get a good product, as well as allowed me to be creative in how I decorated my finger through post-processing techniques.

Steps I took to create my purple fingers

1. Creating my finger mold and cast

To create the mold for my fingers, I first utilized alginate molding powder, which I created via combining 33 g of alginate powder with 125 g of water, mixing it with a popsicle stick in a silicone cup until it had the consistency of pancake batter. I then inserted my fingers and held them in the cold and slimy liquid for five minutes. During this time, the alginate dried much faster than I thought, becoming bouncy and squishy when it had finished hardening. I then slowly unstuck my fingers and pulled them out.

Pictured above is the alginate mold created of my fingers, post-pulling them out

I then created the plaster of paris mixture I would pour into the mold to get the cast of my fingers. I created this by combining 2 parts of the plaster of paris and 1 part of water in a small silicone cup, and mixed with a popsicle stick. I mixed this until it had a pancake batter like consistency. I then poured this mixture into the alginate mold and inserted my jig with my two screws into the respective finger holes in the alginate mold.

Pictured above is the plaster of paris poured into my alginate mold with the jig and screws inserted into the mold

I then let this harden for 24 hours before returning to pull out the plaster of paris cast product. However, the first two times that I performed the molding and casting steps I ended up with broken fingers, causing me to have to repeat the molding and casting three times before getting fingers that I could use. I found that the reason why my fingers kept breaking was that the plaster of paris never fully dried, making it more fragile when pulling it out of the mold. On my third molding and casting process, I decided to take the mold with the plaster of paris inside to dry, and this helped the plaster of paris become more dry, leading to my successful casted fingers.

Pictured above are my casted fingers that I was able to obtain after three casting and molding iterations

NOTE: One of the fingers broke in half still, however, I was able to super glue it back together and post-processes it to hide the crack a bit.

 

2. Post-processing my fingers

Since one of my casted fingers was semi-broken, I decided to superglue it together, which helped make it one piece again. I then moved into sanding down my fingers using 80 and 180 grit sandpaper to ensure that the sharp edges disappeared. I also tried to sand down some of the finger nail area as material was rough in this area.

For my finger, I decided to try to use purple as it is one of my favorite colors. Therefore, I got the purple spray paint and clear gloss finish spray paint and sprayed down my fingers.

Pictured above is the result of my initial spray paint job without the clear gloss coat sprayed on

I then decided that I wanted to make my finger look a bit more realistic by adding in more details using the acrylic paint. Therefore, after the spray paint on my fingers dried, I painted with acrylic paint and small paintbrushes to create my final product.

Pictured above is my final product

Reflections and Challenges

1. I was able to learn how to efficiently mold and cast by performing three iterations of my finger, as well as what conditions are best for the casting material to harden.
2. I was able to practice my spray painting skills and learned how to create a shiny look on my finished product.
3. I was able to utilize painting skills via the acrylic paint I used on the fingers to give them a more realistic look.
4. I did have to recast and mold my fingers three times due to the fingers continuously breaking. I believe the issue was the moist air in the outdoors which caused the plaster to not be able to dry properly, however, it might also be the combination of the usage of the alginate and plaster or paris, as the alginate stays quite moist no matter how long it is left drying for.
5. I did have an issue with one of my finger nails having a small hole in it, however, I could not find the filler spray paint. I asked other classmates and an instructor, however, no one seemed to be able to find it. Therefore, since I did not have another chance to come into the OEDK before the project was due, I had to just paint over the small hole in the fingernail.

Cost analysis

Cost Type	Cost	Price	Source	Quantity	Total
Materials	Plaster of Paris	$7.99 for 4 lbs	michaels.com	0.20 lb	$0.40
	Alginate	$18.25 for 1.5 lb	amazon.com	0.25 lb	$3.10
	Jig	$8.99 for 50	amazon.com	1	$0.18
	Screws	$7.99 for 165 pieces	amazon.com	4	$0.19
	Sandpaper (grit 80)	$10.56 for 10 sheets	amazon.com	¼ of a sheet	$0.26
	Sandpaper (grit 180)	$10.34 for 12 sheets	amazon.com	¼ of a sheet	$0.22
	Silicone cups	$15.99 for 2	amazon.com	2	$15.99
	Popsicle sticks	$22.98 for 100	amazon.com	5	$1.15
	Acrylic paint	$44.99 for 16 bottles	amazon.com	¼ of bottle of black ink	$0.70
	Spray paint	$5.98 for 12 oz (purple)  $12.38 for 2 (clear gloss)	amazon.com	1 oz 2 oz	$0.50 $1.03
Labor	Molding and casting engineer	$37/hour	ziprecruiter.com	4 hours	$148
	Facility Cost	$0/hour	Outside	4	$0
Total $171.72

Picture of clean space!