The Successes and Failures of Molding and Casting a Weird Wall Hook

The goal of this project was to create 2 replicas of my fingers that can be used as a wall hook through casting and molding. In reiterating this process I learned about the process of using alginate and plaster to mold objects and am able to replicate this process. I repeated this process with 2 different types of alginate and plaster so I was also able to adapt to these different materials.

The first iteration:

This mold went smoothly until I realized the plaster was seemingly not going to solidify after 30 minutes. I used too much water in the plaster mixture and as a result I had to wait until the next day for the mold to finish. I also put the screw in poorly, causing it to protrude slightly from the mold.

The second iteration:

With this mold there was new plaster and alginate, so the process of creating the solutions were slightly different but still generally the same. The mistake I made here was that after the mold was finish the plaster wasn’t very strong, and so when I applied too much force trying to pull it out of the alginate the mold snapped in half. I could have easily avoided this by cutting the alginate. I also misunderstood the plaster solution, mixing it 1:2 with water as opposed to 2:1 so this likely contributed to the low strength of the material and the long curing time. Finally, I only used one finger in the mold as opposed to two which could have also contributed to the weakness of the mold with it’s small diameter causing fragility.

The third iteration:

I conquered all of my past mistakes and was able to finish a solid mold of two fingers without any problems in the manufacturing process. (I wish…) The second plaster is much more fragile than the first, because my third iteration ended up snapping, and I needed to superglue the pieces together. This taught me I have to be extra extra careful with taking the plaster out of the alginate.

The cost:

(~6 oz Plaster of Paris) x (3 iterations) = ~18 oz Plaster of Paris

(~8 oz alginate) x (3 iterations) = ~24 oz alginate

~6 paper cups, ~6 popsicle sticks

~32 oz water

~30 minutes per mold, ~1.5 hours of labor not including plaster curing wait time

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