Molding and Casting! | ENGI 210: Prototyping and Fabrication

We began the molding and casting process in class by weighing out 1.5 oz of alginate and 6.75 oz of water. Tyra and I added the water to the alginate bit by bit, using a mixer bit attached to a drill to get rid of clumps in the mixture. We should have cleaned the cups and bit before hand, since we were sharing materials with other groups and it left undesired residue even after mixing heavily. Tyra and I each put a finger into the mixture and began to wait… and then I passed out.

I tried to keep my finger in the mold as long as possible as I lowered myself to the ground. Thank you to Tyra for carrying me inside and labelling our containers after I went home. Unfortunately, our fingers were not in the mold long enough for it to set, so I came back over the weekend to redo the entire process.

Learning from my previous mistakes, I cleaned all materials before I started measuring and mixing. After five minutes of standing, I successfully pulled my fingers out of the set mold. I then weighed and mixed 20g of water into 70g of rockite and poured the mixture into the holes of the mold. I suspended screws in the mixture using the 3D printed jig and masking tape. I left the mold and rockite to dry for 2 hours before carefully removing the alginate mold.

To post process my two fingers, I used metallic silver spray paint. I wish I had discovered the foam block to use as a stand before I painted my fingers, since the coat turned out more uneven then I would’ve liked. Finally, I used the gloss clear coat to seal my fingers. I don’t love the effect this had, as it caused some separation in the paint. I think I might have to spray a thinner coat of sealant and wait longer in between coats.

Overall, I love how my fingers turned out. The molding process is really cool in that it captures every single detail, including the chips in my nail and the specific wrinkles of my knuckles. The silver paint makes them feel like weird old antiques. Moving forward, I want to create a wood base using the CNC machine and make one of the fingers into a ring stand to hold my jewelry.