Making moulds with Plaster

Making moulds for ceramic work is easy and affordable. To make bowls you can either spray the bowls with a release agent, such as silicone or cover the bowl with a clay layer. This means you can etch or alter the shape to suit before pouring in plaster.

To make my heart mould I formed a solid heart shape and pressed it firmly to the base of a plastic container. After pouring the plaster I jiggle the container to release any bubbles.

Once set, the plaster mould can be easily removed and used. When creating wall hangings it’s important to consider how the piece will be hung. I attach clay using a vinegar and water mix to help with the blending of the clay. Using a small 2cm long piece of straw I cut a hole, so the wire can be used for hanging the ornament when finished.

After about a week of drying, weather dependant, the pieces can be put into the kiln for a bisque firing up to 1040oC. Then once the glaze has been applied, the pieces will receive a second firing, up to 1200oC. Complete.

Gnomeo Gnomeo…

Found this wee guy at the markets
Found this wee guy at the markets

I love making concrete art. The problem is, that in order to make my own moulds, I need to use liquid latex, which doesn’t smell to good ; )

I start with my original, and apply a layer of liquid latex using a paint brush. The latex takes approx. an hour to dry on a warm day. I keep repeating this painting of latex layers, until the colour has changed from a white colour to a yellow/brown colour – about 20 layers.

Mould latex Mould latex

I lie the latexed gnome so he’s level, on a rolled towel and press a thick line of clay around the edge of the gnome, dividing him in half. I oil the layex so that the plaster of paris mother mould comes away from the latex once dry.

Latex mouldLatex mould

I sieve the plaster of paris with water, enough the make a slurry. I use a spatula to spread the plaster all over the first half of the gnome. I find it easier to use my hands, to pat it down, making sure it is in every nook.

Mould latex

Once the first side has dried, I flip the gnome, and remove the clay guide. I rub Vaseline along the plaster edge, so the next side of the mother mould will not join the first.

Repeat the application of plaster to form the second side to the mother mould.

Mould latex Mould latex Mould latexMould latex

When the two sides are dry they can be separated from the latex mould. I use a blunt knife to wedge between the two halves. If the mother mould happens to break don’t worry, because the pieces can be held together using a bandage ; )

Mould latex Mould latex

I use towels to help stabilise the mould in a bucket, ready for the concrete pour.

Mould latex oct3 045

I use a mixture of 1:2 Portland cement : Washed Builders Sand and enough water to make a nice slurry. I glove up and use my hands to mix the concrete, getting rid of any lumps. After pouring, I shake and jiggle the bucket, trying to get rid of the bubbles within the casting. Spraying the mould with oil prior to casting can help reduce bubbles, and aid in removing the cast from the mould once set.

Concrete gnome

I get my liquid latex from http://www.triginstruments.co.nz

Kids Market-ing

I love trying to get my kids into making money. Community markets are a great way to teach them the basics of working for their money. Last year I used Vistaprint, and produced stickers for them to sell. I created the image and added the towns name.           If the kids wanted to spend money at the market they had to first earn it, even to buy their lunch!

This year we added plaster crafts to the table, for other kids to buy to take home and paint.

Using a collection of moulds, made with liquid latex, purchased from Trig Instruments, the kids and I worked as a team to produce a selection of plaster crafts. As they were made the morning of the market, once out of the moulds I put them in the oven on a very low heat to speed up the drying process.

The kids also had poster paint at the market, in case kids wanted to paint them while there, and had plastic plates for them to take them home on.

moulds molds 3 011 3 012 3 013 3 022

http://www.triginstruments.co.nz