How to Use a Kiln Sitter

Ceramic kiln
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  • 01 of 05

    The Kiln Sitter's Exterior Panel

    The outside panel of a kiln sitter, prior to placement of the pyrometric cone or rod.
    The outside panel of a kiln sitter, prior to placement of the pyrometric cone or rod. Photo © 2008 Beth E Peterson

    Nearly every electric ceramics kiln comes equipped with a kiln sitter. Before your first firing in an electric kiln, it is essential you become familiar with the kiln sitter; most electric kilns will not operate unless the kiln sitter is properly armed.

    This is a view of the exterior panel of the kiln sitter. Note that it has a hinged plate that swings upward and a latch that can catch and hold the plate. When arming the kiln sitter, you will lift the plate up and hold it in place flush to the panel.

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  • 02 of 05

    The Interior Parts of the Kiln Sitter

    The interior view of a kiln sitter.
    The interior view of a kiln sitter showing the two support prongs and the lever bar. Photo © 2008 Beth E Peterson

    The kiln sitter extends from the exterior panel to the interior of the kiln. Here we see the interior parts of the kiln sitter. The round pipe is made of highly refractory material and helps protect the unexposed portions of the kiln sitter from the high temperatures. The two prongs and the lever bar are all made from highly heat resistant metal.

    The prongs will support the pyrometric rod or cone used. The bar is the end of a lever whose other end is the latch on the external panel.

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  • 03 of 05

    Load the Pyrometric Rod or Cone into the Kiln Sitter

    The pyrometric cones or rods must be properly placed into the kiln sitter.
    The pyrometric cones or rods must be properly placed into the kiln sitter, so that the lever will drop as the cone or rod bends. Photo © 2008 Beth E Peterson

    To load the kiln sitter, lift the plate on the kiln sitter's exterior panel and position it behind the latch. Lift the interior lever bar at the same time. This will cause the exterior latch to drop, thereby holding the plate into position.

    Keeping the interior bar elevated, slip the proper cone or rod between the prongs and the upraised lever bar. Allow the bar to gently drop onto the cone or rod. The kiln sitter is now loaded.

    Make sure to load the kiln sitter before you finish stacking or loading the kiln. It is extra work and added possibility of damage to ware to have to partially unstack the kiln because the kiln sitter had been forgotten.

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  • 04 of 05

    Of Cones, Rods, and Kiln Sitters

    The proper placement of a pyrometric rod in the kiln sitter.
    The proper placement of a pyrometric rod in the kiln sitter must be done before the kiln is stacked. Photo © 2008 Beth E Peterson

    When using a kiln sitter, you need to determine which pyrometric item you will use. To begin, we can narrow the field down somewhat by eliminating large pyrometric cones, including those that are self-supporting. Small cones (sometimes referred to as junior cones) were developed for use in electric kiln sitters. Later, pyrometric rods were also developed.

    The difference between the small cones and the rods is that the rods do not taper. Thus, rods consistently bend enough to shut off the kiln at the cone they are rated for. This is not the case for small cones.

    If the small cone is placed to one side or another, the experienced potter can adjust the kiln's ending temperature by a noticeable amount. Centered on the prongs, the small cone will bend (shutting down the kiln) at the proscribed cone rating. If the lever bar is resting on a thicker portion, it will be a hard firing. If the lever bar is resting on the thinner portion, it is the equivalent of a tipped firing.

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  • 05 of 05

    Arm the Kiln Sitter

    Kiln sitter loaded, with plate properly placed and ready to begin firing the kiln.
    Kiln sitter loaded, with plate properly placed and ready to be armed by pressing the button. Once the button is depressed, the kiln is ready to begin firing the kiln. Photo © 2008 Beth E Peterson

    Once the cone or rod has been placed in the interior portion of the kiln sitter, the sitter must be still be armed in order for the kiln to function.

    Double check that the plate is held by the latch on the extreior panel. Once the kiln has been loaded and you are ready to begin firing, push the button that is now inset in the open area of the plate. This will close the electrical circuits, allowing electricity to flow into the kiln's switches or controller. The kiln sitter is now armed and ready for firing.