I struggled with this homework far more than I anticipated. We were assigned to make a mold of our finger making a hook-shape so that it could be used as a wall hook. Full disclosure, the project had really freaky vibes the entire time and raised my anxiety levels whenever I thought about it (yikes!).

Due to a series of unexpected personal events, I started my project around 8:00AM on Monday morning on the day of the due date (yikes again!). Being very aware of the time constraint on my production process, I planned out the steps I would take and materials I would use to fabricate my pieces in order to optimize time.

I intended to quickly form two Alginate molds so that I had a backup in case the other broke, then to use the quick-curing concrete “Rockite” to fill the mold after it was completely dried (I wanted Rockite because of its convenient dry and cure time of 30 minutes). After the Rockite was dry and firm to the touch, I would then apply a quick coat of spray paint and then later a clear coat.

Upon my arrival at the ENGI 210 table, this plan was doomed. First, the table was completely trashed, and I had to clean for 15 minutes just to have a small workspace. The second issue was that several of the material bags had been left open overnight and had discolored a bit–particularly the Alginate. I was very concerned that the mold would form poorly as a result of the powder’s exposure to the watery air for so many hours (I do believe that this impacted the consistency of the mold a bit and contributed to some air bubbles, but it did not drastically affect the mold making process). And the third, most crucial issue I faced was that the Rockite had been completely used up. I searched for other quick-curing casting materials for a few minutes and even made an attempt to learn about the liquid resins, but at the end of the day I ended up using plaster and missing my morning classes to finish the project (yikes a third time!). I also made the incorrect assumption that we were out of plaster because it was not out on the table with all the other casting materials.

I began making my Alginate mold. In order to mitigate the increased concern for air bubbles, I mixed the Alginate and water very carefully, stirred the mixture aggressively, and then vacuumed out as many bubbles as I could before setting my right index finger in place for the Alginate to cure. I repeated this process one more time to produce two molds that were similar.

I then examined two materials that weren’t plaster in an attempt to produce my cast objects quickly. The first material made by Accu-Cast did not hold together well enough to pull out of the mold. I made a small sample of this and found it best to use something else. The second material was a two-part liquid resin which cures in 10 minutes. I poured this into the test sample I made in the first material and thought it was pretty cool. However, I was not confident enough in my ability to use the liquid resin to risk destroying my molds, so I decided against that as well.

It was about 10:00AM at this point, and I began to panic because none of the materials seemed that they would be ready in time. And about this time, Kaede comes to the ENGI 210 table to make her final attempt on the casting project using plaster. We made our batch of plaster together and quickly cast our pieces at about 10:30AM.

When it came time to remove the cast pieces (11:45AM), I decided to destroy the molds in order to remove the cast fingers undamaged. This was primarily motivated by the very brittle material property of the plaster (cured concrete could have wiggled free just as my finger had when I first removed my hand).

Because the part was still a bit damp, I tap dried the piece using paper towels. As the piece dried, I noticed that the fingers remained very powdery even after they were dry to the touch. Accordingly, I decided to use a colored spray enamel with a clear coat of enamel instead of spray paint. I chose a dark green enamel color because we had it and the darker paint helps to conceal the inconsistencies in the two fingers.

 

Evaluating the cost:

• Design Cost
  • The time needed to fabricate this piece was 4 hours. ($30)
• Consumable Cost
  • The approximate value of the Alginate used is $12 ($6.95/lb)
  • The approximate value of the Plaster of Paris used is $3 ($5.68/4-lb bucket)
  • The approximate total value of non-performance spray enamel used is $1 ($9.44/can )
• Machine Time
  • None!

Total Expense: $46