How sometimes art class is like going to the dentist
Kath Weider-Roos is the Creative Arts Producer at A&D. She snaps photos and asks questions.
Now lie back in your chair, please. Sorry, we don't have the full body bibs they give you at the dentist's office, so here, use this cardboard box to protect your clothing....
Now, sit still, we're going to fill your mouth with a pleasant-tasting neon-pink goo, otherwise known as alginate, a mold-making material used to make dental crowns...
...or, in this case, personalized cup holders.
Let me explain.
These are students in TMP: Construction (Tools, Materials, and Processes) who have been traveling from studio to studio, getting a whirlwind tour of various media. They've arrived at the ceramics studios where Roland Graf and Jeremy Brooks will introduce them to the art of mold-making, a construction technique that's used in clay but also in bronze, plastics, product design and more. As Roland points out to the class, almost everything around you, if it's manufactured, has been created out of a mold. Making a mold is a tricky process since it requires you to think in the negative.
The students will be making two molds: a plaster mold for a clay object (the cup) and a clay/alginate mold for a plaster object (the sculptural stand or cup holder.) The end result will be two sets of sculptural stands for two cups. Each stand must incorporate a life-casting of the student's own mouth and a slip-cast clay cup, one that is faithful to the original mold and the second one varied in a way that conceptually connects the vessel with the sculptural stand.
First the students will create a plaster mold for the clay cup.
Jeremy, below, is a master at slipcasting and in his own creative practice loves the tension that can occur when you use mass-production techniques like slipcasting to create one-of-a-kind objects. Here he shows the students a few techniques for altering the cup form once it has been removed from the mold.
Creating the mold for the mouth is a multi-step process which, as you saw above, starts with a spectacular pink beard formed out of alginate.
After the alginate is poured in the desired formation, students must sit still for 15 minutes as the alginate sets.
After it sets, the alginate is ready to be removed and a perfect negative formation of the chin and lips is left in the rubbery mold. This will be eventually be filled with plaster to re-create the student's mouth gesture.
But first, the students will need to add clay to the alginate mold and begin to the shape the mold for the sculptural stand. They have three hours before the alginate will begin to shrink and harden, so they will need to work quickly to complete their mold.
It's important to even out and work the clay until your mold is exactly what you want -- the plaster will pick up any imperfections that are left on the clay or the alginate.
Below Roland show the students how to create a perfect rectangular shape by adding boards around the mold. All the cracks must be well sealed so the plaster won't leak through.
This mold is almost ready to go but it still needs a recess where the cup will fit. Jeremy demontrates how to create a positive mold by pressing a piece of clay inside the edges of the cup.
Next, this mold for the cup holder must be positioned on the base mold.
After the clay mold is sealed and ready, it's time to mix the plaster.
Students will have to estimate the amount of water that will create a good size plaster base and then add plaster using what's called "the floating island" technique. They will add just enough plaster to form a volcano-like shape just below the surface of the water.
Once the ratio is set, you need to mix it with your hand for three minutes, getting rid of all clumps. Then after you have removed any bubbles in the mix, you have two minutes to pour the plaster into the mold before it begins to set.
The plaster will take 20 minutes to fully harden in the mold.
Next comes the best part of the process: removing the mold to see the final sculpture.
Then you'll need to wash off any excess clay.
Finally, the sculpture will be fine-tuned and any imperfections corrected using an array of tools for scraping, shaping and sanding.
And, voila, the perfect coffee cup holder. No more rings on the table, no more wondering-- "uh, is that my mug?"
Not bad, for a crash course. I especially like these below which unfortunately, are completely useless for drinking coffee...