Introduction: Saggar Fire Ceramics in Your Fireplace, Furnace or Bonfire!
Are you into ceramics, beginner or pro, and sometimes wish you could be more invoved in the firing of your pieces but dont have a kiln at home? If you, like me, are somewhat of a pyromaniac and take every opportunity to light a fire - this instructable is for you! I will explain how to make a saggar - shell out of clay and paper that you can put in any open fire with your pieces inside to get a beautiful, black, metallic surface without any glazes or artificial additives. It's easy!
You will need:
To put in the shell:
Bisque fired (fired once), small decorative ceramic objects. Burnished pieces are perfect for this method, but other textures can work well too. Since the pieces will not be fired to a high enough temperature to make the clay water tight, functional pieces (like cups or bowls) are not ideal to use here.
Sawdust/wood shavings (or straw or shredded paper from one of those machines that shreds your top secret documents at the office). Basically anything dry that will easily catch on fire.
For making the shell itself:
Dry,crushed, pieces of scrap clay, about a small bucket of it (amount depending on the size of the package you want to make). Its good if the clay has a lot of grog/chamotte in it to prevent shrinkage. If you have access to fine sand, that can be mixed into the clay too.
Old newspaper - again, the amount needed will depend on the size of saggar you are making.
And of course: A fire. It will need to be burning rather vigorously for a few hours. It can be a fire place in your house, a fire pit, a bonfire at the beach or a wood fired furnace in your basement. As long as you can fit your package in the fire and make sure that no logs get violently hurled at it, you are good to go!
Step 1: Start Wrapping Your Pieces!
Lay down a few sheets of newsprint, so you have a big enought sheet to comfortably wrap your object/objects. Use sticky tape to stick the sheets together if you need more than one sheet. Put a layer of sawdust or wood shavings or what ever combustible material you are using on the paper, put your piece/pieces on it an add more sawdust. Your pieces should be completely covered in it*. Wrap the newsprint around the whole thing and tape it so it stays closed and no sawdust can leak out. No need to make it look good, as long as it's holding together and you can move it around without the peieces are falling out or the package opens up... That would be bad. If you can't move it around at this stage, you either have too many pieces in the package or your paper is too thin or not tape together well enough. Wrap the package in more paper and tape if necassary to make it handleable. When you are done, it's time to get messy with the clay!
*So why are we putting all this stuff in the package? Well, without getting too technical here, it's when this combustible material inside the closed package catches fire, which it will spontaneously when it reaches a certain temperature, that the magic happens. Since there is a lack of oxygen in there (the package should be intact to achieve this of course), the material that wants to burn will draw oxygen residue from whatever it can and your ceramic objects happen to have a little of those in it. During this process carbon is formed on the surface of the clay when the oxygen is removed and colors your objects black. It's not a black you can scrape off or wash off though, it goes deeper than that and gives a beautiful metallic finish to burnished obejects. After the firing you can use beeswax or other wax to polish your piece to make it even more shiny and somewhat more water resistant.
Step 2: Make the Slip
This step is preferably done several days ahead of when you are planning on make your package, because of the time the clay needs to absorb the water.
This saggar, or shell, will be made using a method very similar to papier machè, but instead of glue we will be using clay to stick the sheets of paper together. When the big blob is fired, the clay will solidify, turning to ceramic, and there will be a hard shell to protect your pieces in the flames and create the oxygen lacking atmosphere we are looking for. So lets make some slip!
Take your dry clay (yes it's easier if it's completely dry) and smash it to as small pieces as your patience allows. Do this outdoors and use some kind of mask so you don't get silicosis from breathing in the clay particles. Mix in some fine sand or more grog/chamotte if you have some at hand. When you have about a small bucket full of crushed dry clay, pour some hot water on it. Just enough to cover the clay, better not to pour too much on because we want the slip to be fairly thick. Now, even though it is tempting to start stirring it - DON'T! Just let the dry clay sit in the water for a couple of hours or, even better over night. Or for several days. If you leave it for a long time though, you might want to cover the bucket or pour more water on it if any has evaporated.
Now, when your clay has absorbed the water at it's own pace, you can start stirring it and it should quickly turn into a porridge like consistency. Add more water if neede, it should not be runny though and form peaks when you lift up your stirring utensil from it. Done! Now lets get dirty!
Step 3: Messy, Dirty Job - But Someone Has to Do It!
Ok, so, now lay down a few sheets of newsprint and scoop out a handful of clay from your bucket of slip and smear it, not too thinly, on the under side of your package. Put it down on the paper. Smear clay on the rest of your prepared package and fold the newspaper over the sticky clay and stick it to the blob. Cover the edges of paper in clay too. Now, as with papier machè, keep adding layers of paper, I just use whole sheets, it doesn't have to look good just be fairly evenly thick and covered all over. Add layers of clay and paper until you have about 4-6 or so layers and your shell starts to feel stiffer and keeps it's shape. Let the last layer be a clean sheet of paper. The paper will actually burn during the firing, but the layers of clay will by then be solid enough to not need the support of the paper anymore.
The package now needs to dry until its completely dry. I usually put it in my electric household oven on about 100°C over night, but it can definately dry in room temperature or outside in the sunshine. Put it on a rack of some sort if possible so it dries all the way around.
Ok. Ready to fire?
Step 4: Fire!
Now, time to fire. I heat the house I live in by firing wood in a wood fired furnace. It's terribly efficient and burns on a very high temperature for many hours. This is ideal, but not necessary. You can also put your package in your fire in a fireplace, a bonfire or even in a larger barbeque. The important thing is that you cover the whole package with firewood and that the fire will burn brightly for at least 3-4 hours, more if you have time. Be carful not to crack the package or throw logs on it. But make sure it is surrounded by the flames at all times. Let the flames die down by themselves and the package to cool slowly. I know, I know...you can hardly wait! But, ceramic doesn't like sudden changes in temperature so try to contain yourself. Go bake some cookies, read a book or plot evil plans to take over the world until the package is cool enough to touch with your hands.
Step 5: Crack the Egg
Here comes the moment of truth. Did it work? Use a hammer and a screwdriver or some other approriate tool at hand to crack the shell. Careful not to brake the things inside! Unpack your gift and analyze the results.
Hope it all worked out for you! Feel free to ask me any questions and I'll try to answer!
Have a claytastic day!
8 months ago
6 years ago
I can not wait to try this! Thank You so much!
6 years ago
I have heard of this before but not so well explained. Thank you.
Reply 6 years ago
You are welcome! Glad you liked it!
6 years ago
6 years ago
I never thought about firing ceramics in my fireplace. That is a great idea.
Reply 6 years ago
Thank you! Yes, and its simple with this method and I really like the finish you get. Let me know if you try it out!