- Build a base by cutting the sides to fit the 36″ plaster board. Glue or nail together or make joints if you are a whizz with a table saw.
- Put the base onto the horses or the stand you will use, where you want your oven to be kept.
- Mix 12 perlite to 2 cement in the mixing tub. Don’t breathe in the dust. Add water and stir. Continue adding water until you get the right consistency for cement.
- Pour the first layer of wet cement into the base and repeat until the base is full. Ideally, the base should be 4″ thick. You will need 3-4 batches. Or just mix it all at once if you are big and strong. Should be dry within 24 hours or less.
- Place the fire bricks onto the cement once it is dry, making sure you have some bricks stick out through the door area. You can then slide your food into the oven easily (not shown in the picture below).
- Now you are going to use sand as a mould for your oven. Put 4 bags of sand into the tub and mix with water. The sand should be wet and hold it’s shape.
- Make a mould of the shape you want your oven to be on top of the bricks. It should be around 15″ high and 22.5″ in diameter.
- Put a layer of wet newspaper over the sand. This will tell you where to stop digging the sand out when the clay is dry hard. I left mine over night.
- Mix 3 parts sand to 1 part clay and water. Not too wet. I used a handy painters cup. This makes it easy to scoop. The clay should hold its shape and not slump down under it’s own weight. Roll the clay into a ball in your palm and put onto your sand mould. Don’t press the clay into your sand, press down to mould the shape. Start with a bottom layer and then add to each layer, going round the entire circumference each time. On the sides, you can use your palm to shape the clay.
- Now cut the door 63 % of the total height of your oven. I just used a long serrated knife.
- Scoop out the sand. I let the oven sit overnight to make sure it was solid enough to hold up without the sand.
- Now a layer of 1 part clay and 3 parts perlite. I will use straw and clay next time. The perlite is not a good finish.
- Finish with a layer of plaster.
- You will need to cover your oven because the rain will damage it. I am going to make a plastic cover but if you have a permanent location, build a hut with a roof.
What You will Need
2 Saw Horses
10 Bags All Purpose Sand
12 lb Perlite
1 Bag Portland Cement
1 1/2 Bags Hawthorn Bond fireclay
18 Fire Bricks
Concrete Mixing Tub
4″ by 3/4″ wood total Length 138″
1/2″ inch Plaster Board
I did not fill the container to the brim with cement. I need it to be transportable, so I just half filled it and then put a layer of sand. When you make yours, fill it to the brim, but have it in the place you want to keep your oven, it will be very heavy.
Your won’t look quite like this. You will have a lip by the door made from the fire bricks to allow the food to easily slide in and out of the door.
You can Google ‘pizza ovens’ and see all kinds of different shapes for ovens. But this is the most practical.
If you hang some rope or chain the width you want your oven, onto a board, the hang of the chain is the exact shape you want your oven to be. You can draw this shape and cut out the arch. The arch can then be used to measure your sand and you can add or subtract as required. I just eye-balled it.
Here we have the next layer of clay, on top of the sand, Step 9.
I started a little fire to help dry this layer, before putting on the clay and perlite.