Many of my ceramic bowls are press moulded inside plaster casts, and I also seem to need an endless supply of moulds for my workshops. Luckily, making moulds using of plaster of Paris is pretty simple and here are the steps;
Place your model bowl upside down on a slab of clay and fix it to the base with a thin fillet of clay. This is important as otherwise the bowl will start to float as you pour in the plaster. I’m using a pyrex bowl because I like its shape, but plastic or ceramic bowls are fine, too.
Start building clay walls around the bowl.
Make sure you leave enough space between the walls and the bowl for the plaster…and fix the walls in their place with clay.
Now mix and pour in your plaster of Paris and let it cure. This will take a few hours.
Remove the clay walls when the plaster has cooled down…I tend to re-use the clay walls as I make several casts in one sitting. 
Remove the glass bowl and there you have your mould. Smooth down rough edges with a sureform and sand paper. It will take a week or so to dry and then it is ready to use.
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Very beautiful and interesting website, i love glaze that you used for big shiny fruits i feel so hungry looking at them! was nice topic about plaster bowl form, I’m doing almost same way just i use bigger plastic pot instead of using clay;) as i have 2 babes i m trying to save time 🙂
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Thank you so much! I like your website, too!
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You’re so talented, to make something out of mud!! I sense this would be very satisfying, spending time this way, maybe some music on or the birds chirruping. Lovely work.
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