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 color and use liquid porcelain clay?

After showing a few times how to make a mould, I thought it was time to show you how to use a mould with liquid porcelain clay. I will also let you know how to color the clay.

Here is what you need: liquid porcelain clay (I poored it in a washing liquid container so that is easier to use), a mould, a glas jar or two, a filler with a sieve, oxide or stains, a sponge and two flat wooden sticks.
First we will color a bit of liquid porcelain clay. Put a bit into a jar.
Add oxide to it.
Stir it a bit an put it through a filler with a sieve so there is no lumps in the clay left and that the oxide is solved well.
Poor it back into the jar so that it has been sieved twice.
When it's ready, poor a bit of the colored porcelain slib into the mould and twist it around a bit.
Then fill the mould with white porcelain clay.
Let is set for 10 minutes.
Poor the liquid clay back into the container.
Put the mould upside down on the flat wooden sticks.
Cut with a knife the edge of the cup away and turn the mould around on the wooden sticks.
After a while, you see that the edges of the clay will come loose from the mould.
Turn it around and the cup will fall out of the mould. Let it stay there for a while until it is a bit dry because it's still soft. Then take a wet sponge and rub it softly around the edges so to get the sharp edges away.
Now let it dry slowly & then fire it.

More crochet experiments

In 2002/2003 I did a lot of experiments with liquid porcelain clay. I had this project in mind and it needed a certain whiteness & transparancy. When the normal liquid porcelain clay turned out to be too solid & not white enough for my taste so I had to search for the right recipe.
It took me more then half a year & lots of sample making to find the recipe that was just right.
People declared me crazy for being so determined to keep on making samples & wait for firing results. I loved the process of it all, it made me learn a lot about the products I used.

In 2006 I started the academy of fine arts with the idea of experimenting of drenching crochet & knitwork in liquid porcelain clay. Due to circumstances I didn't finish the year & the idea was left aside. Now I have my own kiln, I'm superhappy to pick up the idea where I left it.
And I found the jar of porcelain clay that I made in 2002 with a little left over so I had to make a few more samples & drench them in there. I'm convinced that the kind of yarn you use to drench is very important. It needs to be a yarn that holds liquid very well. I used cotton, acrylic, wool, hemp. I also crocheted with a large hook & with a small hook to see if that makes difference.I hope to fire the kiln tonight so I don't have to keep you in suspence too long for the results... I'm quite curious myself! :)
I also added a little sponge in there - but I tried that before and the result is awesome!

Test tiles results

Remember I made these test tiles the other day?This is how they loook after being fired at 1050°C
From left to right I used: Yellow ironoxyde, Synthetic red oxyde, Natural black oxyde, Mangan, Cobalt oxyde, Copper oxyde
A few close ups...
I love how they came out. How about you?

How to make a plaster stamp?

Since I was making a few moulds today, I remembered that I planned to make a tutorial on how to make a plaster stamp. Plaster stamps are not hard to make and they are great fun to use in your modelling projects. You can use regular stamps too but they are much softer so somtimes it's hard to use them for pressing into clay.

Here is what you need: a rolling pin, a cutter, a stamp and a piece of plasticine.
Plasticine is soft clay made of plastic so when you poor the plaster in there, it will come off very easily afterwards.

Take a piece of plasticine and kneed it a little bit.
Make a flat piece with a rolling pin. Make it about 0,5cm or 0,2inch thick

Press a stamp into the flat piece or plasticine.

Make it nice and round with a cookie cutter.

Roll a flat piece of plasticine and twist it around the stamped piece.

Let the ends cross each other and cut the excess plasticine away with a knife.

Press the plasticine clay firmly together on the bottom so no plaster will be able to escape.
Make some plaster ready. 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.
Poor the plaster into the plasticine mould.
You can also poor liquid (porcelain) clay in there and fire the stamp.
Let it set for a while and take the plasticine away. Cut away the rough edges with a kitchen knife.
Now you can stamp your heart out in any modelling material. :)