For many jewellery makers who have dreamed of working with metal but have had nightmares about using the torch, Metal Clay, also called Precious Metal Clay (PMC) and Art Clay, may be their dream come true.
Keep in mind that while you don’t need to use a torch to necessarily solder metals together, it can be helpful to know a little about metal work in order to clean and finish metal clay pieces.
To get started with metal clay, you need a number of basic supplies and equipment. Some of this depends on the clay you pick, since different types of metal clay heat at different temperatures.
Firing the Clay
Depending on the heat required to fire the clay, you have a number of options available including a kiln, a torch, or a hot pot.
Some metal clay will require that you fire it in a kiln because it must be fired up to 1600 F (871 C) in order for the clay to turn into metal. Most kilns, as long as they can reach this temperature, can be used for metal clay, glass fusing, bead annealing, lost wax burn out, and enamelling. Though a kiln may be the most expensive piece of equipment you’ll need, it can have many other applications other than metal clay. Kilns can start around £100 and go up to £800 or more. On average, the larger the kiln the larger the price tag.
Metal clays that require a lower temperature to fire (such as Art Clay Silver 650 or PMC3) require either a torch or hot pot. For the torch, you will also need ceramic tile to set the metal clay on while you hold the torch over it to fire. For the hot pot, which is kind of like a mini-kiln and costs about $50, you need some kind of fuel like butane to heat the pot.
Selecting Your Clay
You may need to figure out the type of clay you will use either before or after you determine if you will use a kiln, torch, or hot pot for firing. Different metal clays fire at different temperatures and have different uses.
Price ranges vary and are dependent on the type of clay you purchase as well as the amount. An average price for 30g of silver metal clay is about £30. For a syringe of slip (a thinner version of metal clay used for decorating or repairing), expect to pay around £12 to £15.
Metal Clay Hand Tools
Once you have your metal clay and a way to fire it, you just need some inexpensive hand tools:
- Roller: In order to roll the clay out, you’ll need a roller.
- Clear Plastic: You will want to roll your clay on a clean surface. A piece of clear vellum works well.
- Graph Paper: Slip this under the clear plastic. The lines on the paper help you line up and cut squarely.
Cards for Metal Clay
- Playing Cards: A few cards come in handy (about 10 or so) when rolling out clay. Put the same number of cards on either side of the clay when rolling.
Cutting Metal Clay
- Cutter: You will need a sharp edge to use to cut the clay. Dental tools, often available at flea markets, are helpful for this.
Smoothing Metal Clay
- Smoother: A tool for smoothing out lines and edges of the clay is helpful. Ceramic stores also carry hand tools for this purpose.
Misc. Metal Clay Tools
- Small Jar: Every scrap of clay can be used. Keep them in an air-tight jar. Water can be added to create your own slip which can be used as a kind of solder by helping to stick pieces of clay together.
- Emery Board: After pieces are fired, there might be some finishing work needed just as with any metal work. Little filing is required, so an emery board or fine sandpaper may be used.
- Olive Oil: Clay can be sticky. Olive oil should be applied to hands and your roller to prevent the clay from sticking.
- Metal Mesh: A small piece of metal mesh is handy for drying clay before it is fired.
- Vermiculite: If you are making three-dimensional pieces such as beads, after they dry, you’ll want to place them in some vermiculite. Then they can be fired in this, and you won’t get a flat side to your piece.
- Textured Scraps: Lace, mesh, and other textured material is great for creating textures in the clay.
- Distilled Water: Occasionally the clay will dry while you are working with it. Dabbing a few drops of water on the clay helps re-hydrate it.
Metal Clay Firing Options
When purchasing metal clay from either brand, you’ll find it comes with temperature and firing instructions. Depending on the type of metal clay you have, from original silver metal clay to copper metal clay, there are a number of options for firing it. This may include anything from a kiln to a simple hand-held torch. Here are some general guidelines for some of the types of equipment you can use for firing metal clay.
All types of metal clay can be fired in a kiln. As long as the kiln can ramp up to the required temperature (as high as 1650 degrees F/900 degrees C) and can hold that temperature for anywhere from 10 minutes to 4 hours, it can be used for firing metal clay. Check the clay manufacturer’s time/temperature requirements to determine how high and how long it must be fired. The main issue with using a kiln, however, is that you want to make sure the temperature gauge is accurate and the length of time the temperature is held is also accurate. If metal clay pieces are under-fired (for example fired at lower temperatures than necessary or for a shorter period of time than required), then the piece will not be fully fired and will be subject to breakage because the organic material will not be fully burnt out of the clay. Programmable kilns, allow you to set the time and temperature for firing, and this means removing any guesswork.
This system is made up of a fibre cone, mesh grid, and pyrometer connected to a butane fuel tank. Because butane burns well above the 1650 degrees F (900 degrees C) mark you need for metal clay, it gets hot enough for firing. It is also less expensive than a kiln and a little more portable. However, there is no way to program this unit, and it is important to keep an eye on it during the process since the firing area of the grid is not enclosed inside anything.
You can pick up a hand-held butane torch at just about any hardware store or jewellery supply company. A torch is about the least expensive piece of equipment you’ll find that will fire metal clay; however, you are limited to the low-fire varieties of clay and the size of the pieces you plan to fire also have a limit of no more than 25 grams of clay. While the firing only takes about 5 or so minutes depending on the size of the piece, obviously since you have to hold the torch as you fire, it will require your complete attention.
Similar to the torch, you are limited to small amounts of low-fire metal clay when using a hot pot, but you have the added advantage of not having to watch it for the entire firing process. I love my little hot pot and have used it for firing all types of small charms and pendants. It is a good way for beginners who may not be comfortable using a torch to get started with metal clay without having to spend that much money.
A regular gas burner can also be used for low-fire varieties of metal clay that are 25 grams or less in size. It’s best to cover the burner with a metal mesh to make sure your piece doesn’t fall into it, and of course, for safety reasons, you can’t just stick something on your fired up burner and walk away. As with all types of firing equipment, proper ventilation is essential when firing.