Saggar firing - POSTPONED

We have sadly had to postpone this event once more. If you have booked you are eligible for a refund or can wait for a new date to be announced. We will email all who have booked. Apologies for the inconvenience. 

--

This is an experimental firing event.

Join Penny de Jong to learn how to make your own saggar parcel to be fired. 

Friday 16 February 6-8pm 

Saturday 17 February, opening the saggars, 3-4pm

Open to all, not just members of the CPA.

WHAT IS SAGGAR? A saggar is a container that bisqued pots are fired in. Saggars were first used to protect porcelain pots from bits of ash that fly around the kiln, but now we use them to trap elements to burn up and colour the pieces inside the saggar package.

On Friday night we will create a package with all manner of inorganic and organic material around our pots: pieces of silver and copper wire, sprinkling salt, copper carbonate, coffee grinds, banana skins, seed pods and more. This will be contained by thick tin foil. On Saturday we will crack open the saggars, much like cracking open a moa egg finding our fossilised pots inside.

The saggar process

Saggar firing is the method of creating confined atmospheres in a kiln within a container or saggar. Depending on the type of firing, the saggar can be made out of anything from the traditional refractory clay to the newspaper. As foil breaks down at high temperatures, we will provide a heavy duty foil to enclose the pots. 

In the ceramic saggar process, various organic and combustible materials can be added including copper wire, seaweed, grasses, flowers, sawdust, copper carbonate, Epsom salts and table salt. Additional oxides can be used to achieve different results.

• Copper carbonate
• Cobalt carbonate
• Red iron oxide
• Crocus Matis

What to bring

• Bring one medium size item or two smaller items bisque ware which would be packed together, one parcel per participant. 
  
• Safety gear – dust mask, apron etc
• Paper shopping bag or similar for your refuse (you’ll be taking this home for disposal)
• Small bucket/ice cream container for the cleanup water
• Non-scratch scourer
• Polishing cloth
• Newspaper to cover the bench area you are working on

Think about what you may want to experiment with and choose a couple of the following inorganic and organic materials. We use a mixture of organic and inorganic materials to create the surface.  

Inorganic material:

• Any copper or silver wire if you can source- any tiny bits (optional) 
• Copper mesh If you can source this, tiny bits (optional), 
• String soaked in brine (I soak the string in the brine from gherkins, then dry out all the seeds as well)
• Steel wool -the one you can pull apart

Organic material must be completely dried out:

You can try any material which you think may add colour or markings to the surface, just be aware that most organic material will just burn out, leaving no marks).

• Horsehair, feathers and the like will not work in the sagger environment.  They are best used in naked Raku)
• Avo skins- one or two
• Banana peels-one or two
• Seaweed- a small piece or leaf of seaweed
• Used teabags-2-3 
• Dried grasses like flax (handy for tying things onto pots)
• Chestnut seed pods or any other seed pod as long as it is dry
• Wood chips or sawdust (a handful or so) 
• Small quantities of everything to experiment with.

Health and safety

As the oxides can be toxic and cause irritation to the skin or lungs, it is wise to wear a dust mask and latex gloves while using them. The environment should be free from draughts to prevent the chemicals from becoming airborne.

The work surface should be covered in the newspaper for easy cleanup. There is usually minimal spillage of salts and oxides onto the work surface because we use aluminium foil.

Terra sigillata

There are differing opinions about whether it’s necessary to burnish the surface of your work with terra sigillata (TS) or not. Penny's prefers the result of a burnished surface, but you can make your own choice.

If you would like to have a go at making your own TS the recipe and instructions are below, or watch Penny's how to videos here. We have a batch of TS in the glaze rooms at the CPA for you to use if that is your preference, take a small pottle.

• Make the surface of your wares as smooth as possible in the making stage.
• When bone dry or nearly bone dry, apply terra sig with a brush. A mop brush is the best for this job. Don’t allow the terra sig to drip or run as this will show up on the finished piece. Beware stray brush hairs – they will leave a mark!
• Allow to dry so that your fingers don’t “snag” on the surface when you rub.
• After each application, burnish with a smooth stone/makeup sponge / plastic bag/back of a spoon/microfibre cloth or anything else that works for you to achieve a glossy surface.
• Apply at least 3 coats to achieve a high gloss finish with a mop brush.
• Bisque fire.
  

Terra Sigillata recipe

600ml warm (not hot) water

300g ball clay OR dry and pulverised clay (your clay body, or porcelain)

1.5g sodium silicate

(Please note: I have used the same ratio of ingredients in the video – just in larger quantities)

Process:

• Pour the water into a 1.5L plastic bottle 
• Add the sodium silicate and shake well
• Add the clay and shake well
• Leave to settle overnight

Decanting the terra sig:

YOU WILL NOTICE THAT THERE ARE 3 DISTINCT LAYERS. We only want the middle layer!

• Make sure the cap is on very tightly
• Place the bottle on a grid inside a plastic container
• Make a hole 1cm above the top of the lowest level
• Slowly open the cap to allow the liquid to flow.
• Close the cap when the centre band has shrunk to about 1cm above and below the hole.