How to make and use a positive mould?

When you make a positive mould, you press clay onto the mould instead of into the mould.
Usually you work with clay plaques and that's what I'm going to do too!
First I'll show you how to make the mould, which is a piece of cake, and then I'll make a little plate that you can use for fruit, chocolates, tealightholders,...
Here is what you need: a bowl, liquid bees wax, paintbrush, plaster, container to mix plaster. I usually use old ice cream containers because that allows me to eat icecream! :)
Take some liquid bees wax and brush it into the surface of the bowl. This will make sure that the plaster won't get stuck on the glass.
Make some plaster ready in the plastic container. Mostly it is made with 1 part of water and 3 parts of plaster but it depends on the kind of plaster you use.
I always go with the pyramid method: you poor the plaster into the water at the same place and a pyramid will form. When the pyramid doesn't suck any water anymore, it's enough plaster and you can start mixing it with the water.
If you like that the plaster will set quickly, you can use lukewarm water or add a pinch of salt.
Mix the plaster with the water. If you don't want rough hands, you better wear gloves.
Then poor the plaster in the bowl.
Shake a little bit with the bowl so that the airbubbles that are in the plaster can come out. Let it set for about an hour.
Then you can take the mould out of the bowl. It's a perfect round & very smooth. It's still damp and needs to dry a few days befor you can use it. I usually put it in the sun,on the radiator or on the lid of the kiln so that it dries quicker.
The mould is dry so now we can use it. Take a piece of clay.
Put it in between two wooden sticks.
Use the rolling pin to roll the clay flat.
When the clay is rolled out, make it a bit smooth with an old credit card. Then place a square piece of paper on top of it and cut away all the edges so that a nice square remains.
I usually put flat pieces on a flat plate of plaster and go over it with a credit card again so that there are no bumps.
Then you take the square and drape it over the mould.
The mould will suck the water out of the clay & the shape will remain.
After a few hours, you can take the dish away from the mould and it looks like this.
I'm too impatient to show it to you when it's fired & glazed, so I just put some chocolates on there so you can see how it will look when it's totally done! :)
You can also use the mould in a different way to make a bowl.
When the clay plaque is rolled out, you drape it onto the mould.
Then take a little wet sponge and press it gently against the mould.Take away some of the excess clay around the mould.Then with a soft rib you go over the clay plaque and press it gently against the mould and make it all smooth.Cut away the excess clay.
Finish the edges smoothly with the soft rib and let it dry slowly upside down.
This bowl holds even more chocolates I think! :)

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How to make a double mould?

Moulds are very useful for repetitive tasks for example if you work with polymer, paperclay, ceramic clay, papier maché,...
Making a mould is not difficult, it's just a bit messy so you better have everything you need prepared beforehand.

This is what you need: plaster, empty icecream containers, liquid beeswax, clay, scissors, knife, doublesided tape, tape, modelling materials (only if you mould claywork), plasterlocks, paintbrush, water, towel. Be sure to protect your surface with a plastic tablecloth and wear an appron if you're messy.The most important thing when you make a double mould is marking the exact middle of the object you want to mould.Make a little bed for the object to lay in. I do that by rolling out a piece of clay and draping it around the object.
Then you need to make sure that it closes tight to the marking line by adding clay and making sure that no plaster can go underneath.
It's a very precise task and it always takes me ages...
Done! I'm satisfied with how it looks.
Now there are two ways to make the locks for the moulds. These are plastic ones that you press into the sides. The advantage is that they make the mould more durable. So if you are going to use it often, I advise you to buy some of these.
The second way is to press a round object into the sides of the object. Plaster will go into those and will give you a bump.I will use the mould a lot so I chose to work with the plastic locks.
Build with plastic a tower around the clay and make sure that there is enough clay on the bottom so no plaster can escape.
Pour the plaster into the construction and let it set.
After about an hour, I open up the construction and you see this...
Take away the little clay bed you made around the object.
Then make sure that the object looks all nice and happy again. You can do that by smoothening it with a credit card or a slightly wet brush.
As I didn't do a very good job on the plastic slots, I decided to add some extra clay around it. It won't matter for the result of the mould.
Since you'll be pouring plaster onto plaster, you will need to add liquid beeswax onto the plaster.
Build the little construction again and fill it with plaster.
After about an hour, this is the result.
Oh, and the object is a full lump of clay - it's not hollow inside as the pressure from the plaster would make it go all wonky.
The mould will need to dry very well before you can use it. I put it on the radiator.
It will be great for much future fun! :)
Enjoy moulding if you start and if you have any questions, please don't hesitate to contact me.

How to make a single mould?

As I have been making moulds the last couple of days, I'd thought I'd share with you how to make them. Moulds are very useful for repetitive tasks for example if you work with polymer, paperclay, ceramic clay, papier maché,...
Making a mould is not difficult, it's just a bit messy so you better have everything you need prepared beforehand.

This is what you need: plaster, empty icecream containers, liquid beeswax, clay, scissors, knife, doublesided tape, tape, modelling materials (only if you mould claywork), paintbrush, water, towel. Be sure to protect your surface with a plastic tablecloth and wear an appron if you're messy.
I'm going to mould an existing bowl. A bowl is an easy thing to mould. That way I can make loads of bowls like this...
Put some doubleside tape on the edges.
Press the bowl onto the placemat so that it sits firmly. Now no plaster can go on the inside of the bowl.
Since you'll be putting plaster on the bowl, it will need to come loose afterwards. That's why you need to put some beeswax onto the entire bowl. If you use clay, you don't need to do that as clay is cellular and will come off easy.
I always safe empty ice cream containers as they come in very handy for moulding. Besides, it's a good excuse to eat icecream. :) Cut off the upper part of the container and place it over the bowl.
Take some clay and press the clay firmly around the container. This way, no plaster can escape.
Make the plaster ready to pour in the mould. The plaster is good if it has the same viscosity then yoghurt.
Place your hand above the bowl and pour the plaster via your hand into the container.
Let it set until it's hard.
Take away the clay and try to get the real bowl out of the mould. If this is hard, you can hold it underneath running water so that it's easier to get it out. Let the mould dry before using it.
If you have left over plaster, don't throw it away but poor it into a container and let it set. You can do fun mouldcarving like this.

Next time I'm going to show you how to make a double mould so stay tuned! :)