Have you ever wondered about the difference between low fire ceramics and high fire ceramics?
When I say ceramics, I mean the kind of clay that needs to be fired in a kiln. A kiln is like a giant high-powered oven. Not everyone has access to a kiln. If you are interested in ceramic, you can find a work around. Visit a local pottery studio or a ceramics shop. Most places have classes and will do the firing of your pieces for you!
Both low and hire fire ceramics are fired at high temperatures, but one much more than the other. Most of my experience is with low fire ceramics. I’m asked about my ceramics a lot, so I thought I’d break it down for you!
Both low fire ceramics and high fire ceramics are a popular and accessible form of pottery that can be made by artists of all skill levels. Low fire ceramics refers to a clay body that is fired at a relatively low temperature, typically between 1650 and 2000 degrees Fahrenheit. I usually fire at cone 06, which is 1828 degrees.
The lower firing temperature allows for a wider range of ceramic glazes and colors to be used, as well as a more forgiving firing process that can be done in a home studio or community center.
When you visit a paint your own pottery studio – you will see a lot of white bisque – raw materials ready to be transformed with bright colors and designs. This is bisque that is made from low-fire clays and/or slip. All you need is to use commercial glazes that the studio offers. Once the glazes/color is added to the piece it will dry pastel and chalky until it goes in the kiln and is fired to a brilliant, glassy finish.
Sometimes these studios will also have stoneware (high fire) pieces for you to paint as well.
Materials for low fire ceramics
Clay: Low fire clay is specifically formulated to withstand lower firing temperatures. Some common types of low fire clay include earthenware and terra cotta. This is the clay I use when I make my sculpted hearts, pasta letter jewelry, stamped clay, etc. It is conditioned and ready to go!
I buy it locally from a warehouse here in Phoenix, Marjon Ceramics. Common clays are Laguna Clay or Amaco Clay. Both are easy to reclaim the scraps to make new clay.
Pottery wheel or slab roller: Depending on the shape and size of the pottery you want to make, you may need a pottery wheel or slab roller. If you don’t have a slab roller, you can use use two wood rulers on either side to create an even layer of clay.
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Pottery tools: Ribs, needles, and loop tools can shape, cut, and texture the clay. Perfect for hand building!
Kiln: It’s a giant oven! Low fire ceramics can be fired in electric or gas kilns. You’ll need to have an electrician look at the outlet where you want to plug in your kiln. You want to make sure it has proper voltage.
Most kilns can use both low-fire and high-fire clays. Ask before purchasing ir using though!
RELATED: Kiln tips for newbies
Glazes: Glazes are used to add color and a protective layer to the pottery. Low fire glazes are formulated to work with the lower firing temperature of low fire ceramics. They come in a wide range of colors, textures and effects.
Shaping and Decorating Pottery
Once you have your materials and tools, you can start shaping and decorating your pottery. Low fire ceramics can be shaped using a variety of techniques, including throwing on a pottery wheel, hand-building with slabs or coils of clay, or a combination of these techniques.
You can also use raw bisque.
About raw bisque
Say you make a mug from low-fire earthenware clay. you’ll need to let it air dry until it is bone-dry. Then fire it to bisque (cone 04) on slow speed. This kiln firing will turn it to bisque. It’s called a bisque fire. Then you can add your glazes and designs and re-fire it at cone 06, medium speed.
When you visit a paint your own pottery studio – that you are painting, bisque that has already been fired once.
RELATED: A beginner’s guide to hand built pottery mugs
When throwing on a pottery wheel, it’s important to start with a centered and balanced piece of low fire earthenware clay. As you shape it, you can use tools to add texture and details to the surface.
Hand-building techniques, such as slab building and coil building, allow for more creative freedom and can be used to create a wide variety of shapes and forms.
After shaping the pottery, you can add decoration using a variety of techniques. One popular technique is to use underglazes or slips, which are applied to the surface of the clay before firing. These can be used to create intricate designs and patterns, and can be layered or blended for a variety of effects.
Another popular technique is to use glazes, which are applied after the initial firing.
Low fire glazes come in a variety of colors and finishes, including glossy, matte, and textured. It’s important to choose glazes that are formulated for low fire ceramics to ensure proper adhesion and durability.
Ideas for decorating low-fire ceramics:
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Firing and Glazing
After shaping and decorating the pottery, it’s time to fire it in the kiln. Low fire ceramics typically require a bisque firing, which is a preliminary firing at a low temperature to harden the clay and prepare it for glazing. This is typically done at a temperature of around 1650 degrees Fahrenheit.
After the bisque firing, the pottery can be glazed using a variety of techniques, including dipping, pouring, brushing, or spraying. It’s important to follow the manufacturer’s instructions for each type of glaze, as the firing temperature and time can vary depending on the specific product.
Once the glaze has been applied, the pottery can be fired again at the appropriate temperature.
Low-fire vs. high fire
Generally, low fire ceramics are fired at temperatures ranging from 1650°F to 2000°F (899°C to 1093°C), while high fire ceramics are fired at temperatures ranging from 2200°F to 2400°F (1204°C to 1316°C) or higher.
One of the main differences between low fire and high fire ceramics is the type of clay used. Low fire ceramics typically use earthenware clay, which is a porous and less dense type of clay that is easier to shape and fire at lower temperatures.
High fire ceramics, on the other hand, use stoneware or porcelain clay, which is denser and more durable but requires higher firing temperatures to achieve full vitrification.
Another difference is the final appearance
Low fire ceramics tend to have a more porous and delicate texture and are often used for decorative pieces, such as sculptures and tiles. High fire ceramics, on the other hand, tend to be stronger, more durable, and more water-resistant, making them ideal for functional pieces such as dinnerware and vases.
The firing process also differs between low fire and high fire ceramics. Low fire ceramics are often fired in a kiln that has been preheated to the desired temperature and then allowed to cool slowly after the firing process is complete. High fire ceramics, on the other hand, require a more controlled firing process, with temperature and atmospheric conditions carefully monitored throughout the firing cycle to ensure proper vitrification and glaze development.
Low fire ceramics are fired at a lower temperature range, using earthenware clay, and tend to have a more delicate texture and porous surface, while high fire ceramics are fired at higher temperatures, using stoneware or porcelain clay, and are more durable and water-resistant. Both low fire and high fire ceramics have their own unique characteristics and can be used to create a wide range of artistic and functional pieces.
I use mostly low-fire ceramics. It’s easier on my kiln because it doesn’t have to work as hard to reach those high temps. However, I do love working with stoneware (high fire ceramics). I think if I venture into stoneware more, i’ll buy a second kiln dedicated to it!
Benefits of low-fire ceramics
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- Lower firing temperature: Low-fire ceramics can be fired at a lower temperature range than high-fire ceramics. This makes them easier and less expensive to fire. , Perfect for hobbyists and beginners who don’t have high-temperature kilns.
- More porous surface. Desirable for certain decorative pieces or sculptures for a more organic, natural look.
- Easier to shape. More malleable and easier to shape and mold than high-fire ceramics. Great for beginners!
- Greater variety of colors and glazes: Access to a wider variety of colors and glazes than high-fire ceramics. This allows for more creativity and experimentation.
- Faster firing time: Because low-fire ceramics are fired at lower temperatures, they tend to have a shorter firing time than high-fire ceramics. Nice for those who need a quicker turnaround.
While low-fire ceramics have these benefits, they also have some limitations.
For example, they tend to be less durable than high-fire ceramics. They may not hold up as well to heavy use or exposure to moisture.
High-fire ceramics offer greater strength, durability, and resistance to water. This makes them ideal for functional pieces like dinnerware and vases.
I hope this article was helpful. Bottom line – go visit a local pottery studio or even take a ceramics class!
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