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Kiln Firing Chart for Pottery and Ceramics [Infographic]

Kiln firing chart for ceramics and pottery

When it comes to firing ceramics, different types of clays and glazes are rated for different temperatures. A kiln firing chart, also known as a cone firing chart, is a useful tool for understanding the effects of temperature on different types of clays and glazes, as well as determining what firing schedule setpoints should be used depending on the cone rating of the media you’re firing.

What Temperature Is Pottery Fired At? Understanding Different Types of Ceramics

What temperature is pottery fired at? Well, that depends. There a three main types of clay that are used to make pottery: earthenware, stoneware, and porcelain. Each of these has different temperature requirements, as well as different properties once fired.

1. Earthenware

Earthenware clay is the most common type of clay used in ceramic firing today. Earthenware is softer than the other types of clay, making it easier to work with and more forgiving. Earthenware also has the lowest firing temperature requirements, which is why it was the first type of clay used to make pottery during the early stages of kiln history.

A collection of fired earthenware pottery to demonstrate the qualities of fired earthenware
Fired earthenware is porous and relatively soft. Earthenware ranges from white and gray hues to browns, oranges, and reds.

Firing Temperature

Earthenware clay typically reaches maturity (or optimum hardness) between 1745° F and 2012° F, although some low-firing earthenware clays can be fired in temperatures as low as 1200° F.

Cone Rating

Earthenware is what’s known as a “low fire” clay. Earthenware clay can be fired from Cone 015 up to Cone 1, but Cone 04 is the average.

Physical Properties

Since earthenware is fired at lower temperatures, it typically remains porous, relatively soft (you can scratch it with a knife!), and still absorbs water. Glazes are often required to make earthenware harder and watertight.

2. Stoneware

Stoneware is a “mid-range” or “high fire” clay that requires higher firing temperatures and a longer firing schedule than earthenware. Once it has been fired, stoneware is hard, dense, and rocklike – hence the name!

A collection of fired stoneware ceramics, demonstrating its hard, rocklike texture
Named for its hard, rock-like texture, fired stoneware is often gray or brown.

Firing Temperature

Stoneware reaches maturity between 2000° F and 2400° F – hotter than lava!

Cone Rating

Stoneware is typically fired between Cone 2 all the way up to Cone 12, with Cones 7 and 10 being the most common for mid-range stoneware and high fire stoneware, respectively.

Physical Properties

Since stoneware is fired at higher temperatures, it has time to fully vitrify, or form a glassy, nonporous bond on its surface. Finished stoneware is durable, hard, and nonporous. Unlike earthenware, stoneware is waterproof once fired even without the use of glazes.

3. Porcelain

Originating in China in 1600 BC, porcelain is a “high fire” clay that produces extremely hard, shiny, often white or translucent ceramics. Also known as kaolin clay (named after Kao-ling hill in China, where it was mined for centuries), raw porcelain is extremely dense and difficult to work. Often, porcelain is mixed with other types of clay to improve its workability.

A collection of fired porcelain ceramics, demonstrating its hard, glasslike white exterior
Fired porcelain is hard, smooth, and glasslike – notable for its white or translucent color

Firing Temperature

Porcelain typically reaches maturity between 2381° F and 2455° F – however, pure kaolin reaches maturity at 3272° F!

Cone Rating

Porcelain clay is fired between Cone 10 and Cone 13.

Physical Properties

Once fired, porcelain is extremely hard and fully vitrified, making it watertight and non-absorbent. Porcelain is noted for its distinct white color.

Understanding Firing Cone Ratings

As we mentioned earlier, different ceramic materials and glazes have a cone rating. Firing cones, or pyrometric cones, are a simple pyrometric device that indicate kiln temperature. Firing cones melt when exposed to a certain temperature for a prolonged period of time. Different ceramics and glazes are given a cone rating to indicate the temperatures at which they’ll reach maturity.

Firing cones range from 022 to 14, with 022 being the lowest temperature and 14 being the highest. As you’ll see on the kiln firing chart below, when a firing cone rating has a ‘0’ in front of it, a lower number indicates a higher fire temperature.

However, for firing cones without a ‘0’ in front of their rating, higher numbers indicate higher firing temperatures.

Kiln Firing Chart [Infographic]

In the kiln firing chart below, you’ll be able to see which temperatures correspond with various cone ratings and materials. The color gradient indicates the incandescence of the kiln at various temperatures, and the column to right indicates how the physical properties of ceramic changes at each temperature.

A pottery kiln firing chart, with temperature labels for each cones as well as insights for what changes occur in the clay at various temperatures.

Download PDF!

Reach the Right Setpoints on Your Kiln Firing Chart with Ease and Precision

The TAP and TAP II Controllers by SDS Industries are the most advanced, precise, and easy-to-use pottery kiln controllers on the market today. With responsive touchscreen controls, an intuitive graphical UI, and integration with the TAP Kiln Controller Mobile App, TAP Kiln Controllers can pair with any relay-controlled kiln or oven to allow you to easily manage and execute your kiln firing schedules.

We invite you to explore our selection of digital kiln controller, standalones, and conversion kits on our online store. You can also purchase TAP Digital Controllers or TAP-Controlled Kilns and Heat Treat Ovens through one of the following distributors:

CTA to shop pages for pottery kiln temperature controllers.

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Understanding Kiln Firing Schedules for Glass, Ceramics, Pottery, and Heat Treat

Kiln firing schedules for glass, ceramics, pottery, and heat treat

The primary function of a kiln controller is to help users input (and successfully execute!) their kiln firing schedules…but what is a kiln firing schedule? Below, we’ll be helping you understand kiln firing schedules, as well as how firing schedules differ for materials such as glass, ceramic, pottery, and metal heat treat!

Definition of Kiln Firing Schedules

A kiln firing schedule is a progression of steps, made up of temperature changes over specific time intervals, that a kiln moves through during a firing. Each step of a kiln firing schedule is made up of four components:

  • Step #: Also known as a ‘segment,’ step # represents the order in which the steps of the schedule occur.
  • Ramp Rate: Measured in degrees per hour, the ramp rate is the speed at which the kiln is heated up or cooled down.
  • Setpoint: Measured in degrees, the setpoint is the desired temperature the kiln reaches during each step.
  • Hold Time: Also, known as a ‘soak,’ hold time is the length of time (defined in days, hours, or minutes) the kiln stays at a specific setpoint before advancing.

Each of these components determines the properties of the finished ware once the firing schedule reaches completion. Even extremely minor variances in adhering to kiln firing schedules can have a major impact on the finished result, so it’s important to accurately input firing schedules into your kiln controller and to utilize kiln controllers that are able to automatically execute kiln firing schedules with extreme precision.

Example of a Kiln Firing Schedule

Kiln firing schedules, sometimes colloquially referred to as programs or firing schedules, can best be described as the road map the controller uses to execute a firing. While kiln firing schedules can string together as many steps as necessary to achieve the desired firing result, below we’ll be looking at an example of a three-step firing schedule:

Example of a 3-step kiln firing schedule in order to illustrate the format and various components of firing schedules

Assuming the kiln starts at room temperature, or 70° F, the example schedule shown above will result in a firing that takes 5 hours and 24 minutes to complete. Below is a visual graph representing the firing profile of this schedule:

A 3-step kiln firing profile plotted as a line graph

In this graph, we can see that the kiln follows a 500 degree-per-hour ramp rate from time 0 (when the kiln was started) to 950 degrees (the first setpoint). Once the setpoint is achieved, the controller regulates the temperature to keep the kiln at 950° for 30 minutes.

Once the hold time from the first step is completed, the kiln advances at a rate of 1200 degrees-per-hour to a setpoint of 1425° and holds there for 20 minutes.

Finally, the kiln moves to step three, cooling at a rate of 300 degrees-per-hour down to a setpoint of 700°. Because the hold time at Step #3 is zero, the kiln firing schedule is now complete!

See our article on Alerts and Alarms so you can be notified when your kiln firing schedule reaches certain firing points! 

Ramp/Hold vs Time-to Temp Schedules

Kiln firing schedules can also be expressed in different formats. The example above is the common Ramp/Hold format, which can also be described as a Ramp/Soak or Ramp/Dwell schedule. This is the most common kiln firing schedule format, and it is also the format that is supported by TAP Kiln Controllers.

However, kiln firing schedules can also be written in a Time-to-Temp format, which contains all of the same information but prioritizes the timing of the firing as opposed to the temperature of the firing.

When generating a Time-to-Temp schedule, you are, in effect, saying “I want to be at 950 degrees in 1 hour and 45 minutes.” At that point, the controller is responsible for converting the defined “Time-to-Temp” into a usable Ramp Rate. By saying we want to be at 950° in 1 hour and 45 minutes, and assuming we’re starting from 70°, we’ve essentially created a firing schedule with an implied ramp rate of 500 degrees-per-hour.

NOTE: Some controllers that use Time-to-Temp format do not report accurate ramp rate, which can affect outcomes of the firing schedule. For instance, a Time-to-Temp controller might report that your kiln went from 100° to 1250° in one minute, because that was what it was programmed to do, even though achieving that level of temperature change over that time interval simply isn’t possible.

Below is the exact same kiln firing schedule from before written in a Time-to-Temp format:

A kiln firing schedule written in Time-to-Temp format

The firing graph for both formats would look exactly the same – and executing either format would yield the same outcome once the firing schedule reaches completion (assuming the controller was capable of converting the Time-to-Temp into an accurate ramp rate). The only difference is how the kiln firing schedule is expressed. What was defined in three steps in the Ramp/Hold format requires five steps in the Time-to-Temp format, despite yielding the same firing profile.

What Factors Does a Kiln Firing Schedule Depend On?

Kiln firing schedules are dependent on the material/media being fired, as well as the physical capabilities of the kiln. There is no one-size-fits-all approach to kiln firing schedules, as the material within the kiln will require its own unique schedule to achieve optimal results. Later in the article, we’ll be looking at examples of firing schedules for glasswork, firing ceramics, and metal heat treat.

Limitations of Kiln Firing Schedules

Now that you know the components of a kiln firing schedule, you should also understand the limitations. The physical capabilities of the kiln dictate certain physical boundaries that cannot be overcome. The material of the kiln, chamber size, power rating, and thermocouple gauge all contribute to the kiln’s demonstrated performance.

As kilns approach higher temperatures, their ability to heat at defined ramp rates begins to fall off. A kiln that can heat at a ramp rate of 3600 degrees-per-hour while at 200° will likely be unable to generate the same ramp rate at 1500°. This is a result of the kiln material and power rating.

Thermocouples are used to read the temperature inside a kiln chamber and communicate that temperature to the kiln controller. A kiln with an 8-gauge thermocouple will respond much slower to temperature input than a 20-gauge thermocouple. This can result in overshoot at low setpoints as the thermocouple needs time to “catch-up” to the heat that has been applied to the kiln.

Kiln Firing Schedules for Glass

While the kiln firing schedule example above was hypothetical, in this section we’ll explore actual kiln firing schedules for different types of glasswork techniques.

Please Note: Each of these schedules is for 90 COE glass. Additionally, each firing schedule will have to be adjusted according to your specific kiln, the size of your project, as well as the type of glass you’re using – some experimentation will be required, so please just use these as a general guideline.

For additional in-depth technical information about using your kiln to fire glass, please visit https://www.bullseyeglass.com/index-of-articles/.

Full Fuse Firing Schedule

A full fuse is when you use heat and time to combine two or more layers of glass to form one single solid piece of glass. The layers of glass fuse together – hence the name! Below is a full fuse firing schedule for projects that are smaller than 12”.

A full fuse firing schedule for 90 COE glass

  1. 400°F/Hr to 1250°F – hold 30 minutes.
  2. 600°F/Hr to 1490°F – hold 10 minutes.
  3. AFAP°F/Hr to 900°F – hold 30 minutes.
  4. 150°F/Hr to 700°F – hold 0 minutes.
  5. AFAP°F/Hr to 70°F – hold 0 minutes.

You can find temperature guidelines for additional glasswork processes here.

Glass Casting Firing Schedule

Glass casting is when you melt glass until it is soft and malleable enough to conform to a mold. The glass then hardens to create a glass object in the shape of the mold. Below is a glass casting firing schedule for a small open face mold cast:

A glass casting firing schedule for 90 COE glass

 

 

  1. 100°F/Hr to 200°F – hold 6 hours.
  2. 100°F/Hr to 1250°F – hold 2 hours.
  3. 600°F/Hr to 1525°F – hold 3 hours.
  4. AFAP °F/Hr to 1200°F – hold 4 hours.
  5. 50°F/Hr to 900°F – hold 6 hours.
  6. 12°F/Hr to 800°F – hold 1 minute.
  7. 20°F/Hr to 700°F – hold 1 minute.
  8. 72°F/Hr to 70°F – hold 1 minute.

Additional details about casting firing schedules can be found here.

Annealing Firing Schedule

Annealing glass is the process of stabilizing glass during the cooling process by holding it at a steady temperature to give it time to strengthen. COE 96 glass is typically annealed at a setpoint of 960°F. However, the size of the glass, its thickness, as well as the number of layers being used determines how long the anneal hold needs to be.

From the example of the Full Fuse Firing Schedule above, we highlighted the steps that involved annealing in green:

An annealing firing schedule for a glass kiln

Notice that Step #3 has the kiln hold at the annealing setpoint 900°F for 30 minutes in order to give the fuse time to stabilize, and then Step #4 and Step #5 have the kiln slowly cooling down from the setpoint to the final temperature.

See our article Benefits of Using a Digital Controller for Glass Kilns for more information about using your kiln for glasswork!

Kiln Firing Schedules for Ceramics

Before getting into kiln firing schedules for ceramics, it’s important to know what Cone # the material you’re firing is rated for. This represents the setpoint at which the type of material you’re using is properly fired. So, for example, Cone 04 clay would need to reach a setpoint of at least 1945°F whereas Cone 6 Porcelain would need to reach a setpoint of 2232°F.

Please Note: All of these kiln firing schedules are for 04 Cone clay. Just like with glasswork, each firing schedule will have to be adjusted according to your specific kiln, the size of your project, as well as the type of clay, stoneware, or porcelain you’re using – some experimentation will be required, so please use these as a general guideline.

Candling Firing Schedule 

Candling is the process of allowing clay to fully dry prior to high temperature ceramic firings. This involves heating your kilns to a low temperature for a prolonged period of time. Below is an example of a kiln firing schedule for candling your clay:

A pottery kiln firing schedule for candling clay

  1. 150°F/Hr to 150°F – hold 12 hours.

Simple, right? However, this is just to get the clay ‘bone-dry’ before firing it, since the natural moisture of the clay, if fired too quickly, can cause your project to crack and fissure!

Bisque Firing Schedule for Cone 04 Ceramics

A bisque firing is the process of turning clay into ceramics! Below is a slow bisque firing schedule for Cone 04 clay:

A bisque firing schedule for Cone 04 ceramics

  1. 80°F/Hr to 250°F.
  2. 200°F/Hr to 1000°F.
  3. 100°F/Hr to 1100°F.
  4. 180°F/Hr to 1695°F.
  5. 80°F/Hr to 1945°F.

You’ll notice that this firing schedule doesn’t include any hold times. However, the total firing time is 13 hours and 26 minutes. So how does that work? In this case, the firing time is dictated by the ramp rate – or the amount of time it takes for your kiln to reach each setpoint in the firing schedule.

Glaze Firing Schedule for Cone 04 Ceramic

When firing pottery, it’s important to match the Cone # of your glaze to the Cone # of your clay. In this case, we’re using Cone 04 clay, which is a “low-fire” clay. Therefore, we’d want to use a glaze that’s in the Cone 06-04 range. In other words, the temperature of the glaze firing schedule shouldn’t exceed the temperature of the bisque firing schedule.

Glaze firing schedule for Cone 04 ceramics

  1. 150°F/Hr to 250°F.
  2. 400°F/Hr to 1695°F.
  3. 100°F/Hr to 1945°F.

See our article on How to Use a Pottery Kiln Temperature Controller for more information on how to fire ceramics!

Firing Schedules for Heat Treating Metals

Just like with glasswork and pottery, kiln firing schedules for metal heat treat is extremely dependent on the type of material you’re using. But, additionally, it’s dependent on the qualities you want the finished metal to have. For heat treat, the rate at which you cool the metal has a significant impact on the molecular structure of the metal. For these examples, we’ll be working with 1095 steel.

Please Note: All of these kiln firing schedules are for 1095 steel. Just like with Each firing schedule will have to be adjusted according to your specific kiln or heat treat oven, the type of metal you’re using, its thickness, as well as the desired properties – some experimentation will be required, so please just use these as a general guideline.

You can find more information about setpoints and cooling rates for different effects on different types of metal here.

Normalizing Firing Schedule for 1095 Steel

Normalizing is a process where metal is heated to an extremely high temperature for a defined period of time and then either air-cooled or furnace cooled at a controlled ramp rate. Normalizing relieves internal stress and ensures uniformity, resulting in harder, stronger metals. Below is a normalizing firing schedule for 1095 steel:

A schedule for normalizing 1095 steel in a heat treat oven

  1. AFAP°F/Hr to 1600°F – hold for 15 minutes.
  2. Remove knife or blade from the oven and allow to air-cool.

Quench Hardening Firing Schedule for 1095 Steel

Quenching is the process where metal is heated and then cooled rapidly by dipping it into an oil, polymer, or water, resulting in very hard, very brittle metal. This increases the hardening of the metal (but also its brittleness). Below is a quench firing schedule for 1095 steel:

Heat treat schedule for quench hardening 1095 steel

  1. AFAP°F/Hr to 1600°F – hold for 15 minutes.
  2. Remove knife or blade from the oven and quench in fast oil to 150°F.

Tempering Firing Schedule for 1095 Steel

After hardening, the metal is heated to a lower temperature to reduce excessive hardness and relieve internal stress. Tempering makes metals less brittle – it should be done within two hours after the steel cools from the quench hardening process. Below is a tempering firing schedule for 1095 steel:

Tempering firing schedule for 1095 steel

  1. AFAP°F/Hr to 400°F – hold for 2 hours.
  2. Allow knife or blade to slowly cool – either air-cooled or within the oven.

You’ll notice that most heat treat applications have simple kiln firing schedules that only involve a single setpoint and aren’t dependent on ramp rate. For this reason, it might make sense to use a single setpoint controller for heat treat applications like the TAP & Go by SDS Industries.

Check out Guide to Choosing Heat Treating Controllers for more information about different types of heat treatments!

The Easiest Way to Precisely Execute Kiln Firing Schedules

The TAP and TAP II Controllers by SDS Industries are the most advanced, precise, and easy-to-use digital kiln controllers on the market today. With responsive touchscreen controls, an intuitive graphical UI, and integration with the TAP Kiln Controller Mobile App, TAP Kiln Controllers can pair with any relay-controlled kiln or oven to allow you to easily manage and execute your kiln firing schedules.

We invite you to explore our selection of programmable kiln controllers, standalones, and conversion kits on our online store. You can also purchase TAP Digital Controllers or TAP-Controlled Kilns and Heat Treat Ovens through one of the following distributors:

Shop TAP Kiln Controllers CTA

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How to Manage Your Kiln Firing Schedule

Blog header image for Managing Your Kiln Firing Schedule

What’s one thing potters, ceramicists, glass artists, and metal workers have in common? Each relies on a kiln firing schedule to produce their finished ware. As you can imagine, kiln firing schedules are not one-size fits all! After all, specific temperatures over specific time periods create specific results.

Below we’ll be exploring the ins and outs of firing schedules – from creation to execution. And we’ll also be looking at how automatic kiln controllers help artists create, manage, and organize their firing schedules.

What Is a Kiln Firing Schedule?

A kiln firing schedule is a progression of steps, made up of temperature changes over specific time intervals, that a kiln moves through during a firing. Each step of a kiln firing schedule is made up of four components:

  • Step #: This represents the order in which the steps of the schedule occur.
  • Ramp Rate: The speed at which the kiln is heated up or cooled down (measured in degrees per hour).
  • Setpoint: The desired temperature the kiln reaches during each step.
  • Hold Time: Also, known as a ‘soak,’ this is the length of time the kiln stays at a specific temperature.

Kiln firing schedules range from extremely simple to extremely complex. For example, some heat treatments for metal may only require a single step with a single setpoint, whereas firing schedules for pottery or glass can include half a dozen steps that require extremely precise inputs and outputs.

Furthermore, different processes for different materials require a specific firing schedule. This may seem like a lot to juggle – and, in the old days, it used to be! In the age of manual kilns and early automatic controllers, kiln operators used to have to shuffle through their firing journals to replicate a specific firing schedule.

Luckily, however, automatic kiln controllers have made creating, managing, and executing firing schedules significantly easier and more streamlined. Modern digital kiln controllers like the TAP, TAP II, and TAP Micro Kiln Controllers by SDS Industries, allow users to select from premade firing schedules or create their own with just a few swipes of their finger from the device’s touchscreen. Additionally, with the TAP Kiln Control Mobile App, users have the ability to create and modify schedules from their smartphone or tablet – or even execute their firing schedule remotely with a premium subscription.

How to Create a Kiln Firing Schedule

SDS Industries designed and launched the original TAP Kiln Controller in 2015 – in large part because we were frustrated with how dang difficult it was to create kiln firing schedules (and then find them later) on the automatic kiln controllers on the market at the time.

A big part of our focus was on streamlining the user experience for firing schedule creation and execution. And, starting from scratch, we had the opportunity to include all the features we’d always wanted on a kiln controller, such as:

  • An intuitive graphical UI and responsive touchscreen controls.
  • Logically arranged menus with full text displays to make it easy to create new firing schedules or modify existing schedules.
  • Alpha-numeric organization for kiln firing schedules to make finding the right firing schedule easy.
  • The ability to star your favorite schedules for even quicker access.
  • The ability to create a theoretically unlimited number of kiln firing schedules, each containing a theoretically unlimited number of steps, so users never have to pick up their firing notebook again (unless they really want to)!
  • Integration with the TAP Kiln Control Mobile App to allow users to create, modify, and execute kiln firing schedules from their mobile device when their kiln controller is connected to Wi-Fi.

Below, we’ll be looking at how to create a kiln firing schedule on the TAP II Kiln Controller UI (schedule creation on the original TAP Controller is extremely similar):

Step 1: Starting from the ‘Home Screen’

Below is a picture of the home screen on a TAP II Kiln Controller:

To access kiln firing schedules, press ‘Start’ on the right side of the screen.

Step 2: Using the ‘Schedule Selector’ Screen to Access Your Kiln Firing Schedules or Create a New One

On the ‘Schedule Selector’ screen, you have the ability to access all of your existing kiln firing schedules by scrolling through the menu on the left side of the screen. Clicking the ‘Edit Icon’ beside the schedule title allows you to edit that firing schedule. Or, to create a new schedule, click ‘New’ on the right side of the screen.

Step 3: Edit and Add Steps to Your Firing Schedule

Clicking the ‘Edit Icon’ will bring you to the ‘Edit Schedule’ screen:

On this screen, you have the ability to add new steps and edit the Schedule Name, Ramp Rate, Setpoint, and Hold Time for each step. Additionally, you have the ability to set alerts to notify you when your kiln has reached its setpoint or hold time for each specific step. When you’re finished editing your firing schedule, click ‘Save.’

Step 4: Execute Your New Firing Schedule

When you click ‘Save,’ the controller will bring you back to the ‘Schedule Selector’ screen. Select your desired schedule and then press ‘Start.’

Execute Kiln Firing Schedule Screen on a TAP II Controller

From there, your TAP II Controller will automatically execute your new firing schedule. From the ‘Execute’ screen, you’ll be able to monitor exactly where your kiln is in terms of your firing schedule, as well as skip steps, access firing logs, or abort your firing.

Schedule Creation UI for the Original TAP Controller

Our partners at Evenheat provide an overview of the schedule creation UI for the original TAP Kiln Controller.

Where Can You Find Different Kiln Firing Schedules?

Manufacturers and distributors often have common kiln firing schedules already programmed into your controller. However, as we mentioned earlier, schedules aren’t one size fits all. Below are some tried and true firing schedules for various types of materials:

  • Kiln Firing Schedules for Glass: Kiln firing schedules for Full Fuse Casts, Contour Fusing, Tack Fusing, Slumping, Deep Slumping, Draping, Fire Polishing, Pot Melting, Bubble Squeezing, Wine Bottle Slumping, and Crackling.
  • Kiln Firing Schedules for Pottery and Ceramics: Kiln firing schedules for Basic Cone 04 Bisque Firing (Earthenware, Stoneware, and Porcelain), Cone 05 Glaze Firing (Earthenware), Cone 05/06 Glaze Firing (Mid-Range Stoneware and Porcelain), Cone 10 Glaze Firing (High Fire Stoneware and Porcelain), and Slow Bisque Firing.
  • Kiln Firing Schedules for Steel: Hardening and Tempering for Steel.
  • Thermocycling a Steel Knife: Forging, Normalizing, Grain Refining, Annealing, and Cooling Cycle for Steel Knives.

However, please note that different materials and techniques have specific temperature requirements. We encourage you to do your research and always follow recommendations for cones and temperature requirements from your supplier for glass, clay, stoneware, porcelain, or metal.

Limitations to Firing Schedules

Now that you know how to create a firing schedule, you should also understand the limitations. The physical capabilities of the kiln dictate certain physical limitations that cannot be overcome. The material of the kiln, chamber size, power rating, and thermocouple gauge all contribute to the kiln’s demonstrated performance.

As kilns approach higher temperatures, their ability to heat at defined ramp rates begins to fall off. For instance, a kiln that can heat at a ramp rate of 3600 degrees per hour while at 200 degrees will likely be unable to generate the same ramp rate at 1500 degrees. This is a result of the kiln material and power rating.

Thermocouples are used to read the temperature inside a kiln chamber and communicate that temperature to the kiln controller. A kiln with an 8-gauge thermocouple will respond much slower to temperature input than a 20-gauge thermocouple. This can result in overshoot at low setpoints as the thermocouple needs time to “catch-up” to the heat that has been applied to the kiln.

Learn More About the Most Intuitive, User-Friendly Kiln Firing Schedule Creation

When it comes to creating kiln firing schedules, the TAP and TAP II Controllers by SDS Industries are the most advanced, precise, and easy-to-use kiln controllers on the market today. With responsive touchscreen controls, an intuitive graphical UI, and cutting-edge kiln controller software, TAP Kiln Controllers can pair with any relay-controlled kiln or oven.

We invite you to explore our selection of automatic kiln controllers, standalones, and conversion kits on our online store. You can also purchase TAP Digital Controllers or TAP-Controlled Kilns and Heat Treat Ovens through one of the following distributors:

Shop TAP Kiln Controllers CTA