This video demonstrates the second process in making some plaster slump molds- mixing the plaster and pouring it in the leatherhard bowls. If you would like to see the video in which I threw the three bowls of graduated sizes please see this link. https://youtu.be/nSYPiIke5PI
This video begins when the thrown forms are a stiff leatherhard, and are ready to have plaster poured into them. The pieces of clay will be waste clay, as when I have used them with plaster, I don’t want to risk the chance of recycling clay with plaster scraps. Plaster bits would cause pop outs during firing, and would ruin a piece. (Much better, in my opinion to discard!)
I ready my area by covering my table surface to protect it, I have a bucket double lined with plastic bags taped to it, water already measured to reach about ⅔ of the bucket, paper towels, gloves *which I taped additional plastic to lengthen them on my arms… and a dust mask or respirator and a trash can close at hand.
I use COLD water in my bucket, and begin by slowly sprinkling the plaster over the surface of the water. Continue until you have sprinkled enough plaster that it makes a little “mountain” which doesn’t go under the surface. When you have reached the mountain stage, begin a gentle mix without incorporating air. Gently mix with your fingers, and break up any bits which form. Keep an active mixing going the whole time. I find it takes about 15 minutes of mixing for the plaster to be ready to pour. You want to be patient, to make sure it will be starting the process of curing so it will stay in suspension. Pouring it too early can result in a weak plaster and water migrating to the top. Don’t use warm or hot water, as although it will speed the curing, it will also encourage chunks to develop.
For the plastic drape mold, I covered it in vaseline to form a seperator.
In the video, I waited about two hours for the pieces to cure before removing and cleaning them. When taking off the clay forms, I flipped the plaster upside down and set it perched on a banding wheel, and then loosened up the clay around all the edges. Once removed, I scraped with mudtools scrapers and kitchen scrubbies. (see my googledoc links or my Amazon storefront for the ribs and shredders.)
I used a Mudtools Shredder to remove uneven corners. (I blanketly call them “surforms” which is technically a Stanley product I first used over 30 years ago. Mudtools are a great option made for clay- but essentially have the same mechanics of the surforms)
I show a few other types of drape molds, and you can find links below to some on my googledoc, or in my Amazon Influencer Store.
Check out my Amazon Influencer Store where I have recommendations for some of my favorite tools and products many of which I use in my videos- which are available on Amazon. https://www.amazon.com/shop/karanspotsandglass
For the great tools I used in the video (including the mudtools long green platter rib and the yellow rib) check out this link to a live Googledoc I continually update with lots of my favorite tools on Amazon using my associate links! (also some non-amazon suggestions on here!)
https://docs.google.com/document/d/1XbYPQjjJnHrQG5xyWGMHZkEcZj5N8VnUAbFZdJRrRmU/edit?usp=sharing
In this video, I am using standard 153, a nice midrange firing stoneware in my classroom.
I am a public high school ceramics teacher at William Mason High School in Mason, Ohio. (Mason is currently the largest high school in Ohio!) As a potter, I have been working in clay for over 30 years, and I have been teaching for over 28 years, the past 20 have been specifically teaching high school ceramics. I love what I do! I have my own studio in my home basement, where I work on my personal pottery for my Etsy site; https://www.etsy.com/shop/KaransPotsAndGlass
I started my Youtube channel to make videos to help my students if they are absent and miss a demo, or if they would like to explore more advanced techniques independently. I have been amazed to reach such a wider audience than my own students!
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