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.’
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:
- Hot Shot Oven & Kiln
- Mobile Glassblowing Studios, LLC
- Jen-Ken Kilns
- Kiln Frog
- Sheffield Pottery