Once you are comfortable throwing cylinders, you may want to take on the challenge of throwing lidded jars. There are several types of thrown lids. Here we will discuss how to throw a basic inset-style lid.
In throwing lids, there are two main challenges. The first is to form the galleryflange. The second is to fit the lid and jar as closely as possible. This requires that you measure the jar and lid accurately, which is best accomplished with pottery calipers.
Begin by throwing a cylinder.
Compress the Gallery Flange on the Inset Lidded Jar
Once the gallery flange has been formed, it is important to compress it. I find it works best to use a chamois, just like when I’m compressing the rim of a pot. Be sure to support the outer wall of the pot with your other hand.
Do not cut the pot free from the wheel yet.
Measure the Inner Width of the Mouth for an Inset Lidded Jar
In order to know how large you will need to make the lid, you must first measure the jar’s mouth. Although this can be done with a ruler, it is much, much easier and more accurate to use potter’s calipers.
As you get ready to measure the inner width of the jar’s mouth, make sure that the pot’s outer wall above the flange is either straight up and down or flares outward slightly. Measure so that an imaginary line drawn between the two points of the calipers go directly through the center…
Create the Thrown Lid for an Inset Lidded Jar
The lid is thrown upside down. What will become the top of the lid is trimmed once the lid is leather-hard. If you wish to form a handle while trimming away the excess clay, you will need to throw the lid as if it has an extravagantly thickened floor. Another option is to attach a handle onto the lid after it has been trimmed.
On a second bat center enough clay to form the lid, plus up to about one pound of extra clay as desired for a handle. Or, if you prefer, you can center much more clay and the…
Finalize the Thrown Lid for an Inset Lidded Jar
Once you have the lid close to the right measurement, clean up any liquid or slip. Check to make sure that the upper quarter inch or so of the lid is at the vertical. Make the groove for cutting the lid free, but do not cut it free yet.
Once everything else is done, use a wooden trimming tool or other straight-edged tool to square out the rim of the lid as shown in the photograph.
Important: Just prior to cutting the lid off the bat or mound double-check the measurements. You will almost certainly…
How to Dry the Lid and Jar
As soon as the clay has stiffened enough not to deform, the lid should be placed on the jar. Since the clay is still fairly damp, there is a possibility that the clay may stick the lid and jar together.
To avoid this, tear strips of paper towel and lay them across the rim and gallery on the jar. I prefer to cover about 75 to 80% of the gallery’s area.
Set the lid and jar aside and allow to dry to leather-hard.
Trim the Upper Surface of the Lid
Thrown lids are trimmed while seated on their corresponding jar. In essence, the jar itself becomes a trimming chuck. Trimming the lid is the same process as trimming out a foot ring. The only substantial difference is in what areas are removed. You may, however, find it somewhat easier if you keep a fingertip on the top of the lid. This will help it not to shift in the jar’s mouth.
If you are trimming out a handle, make certain that you do not encroach into the handle’s area with the…
Bisque, Decorate, and Glaze Your Inset Lidded Jar
Once the jar and lid are bone-dry, bisque fire them. Again, keep the lid in place.
Once out of the bisque kiln, you can decorate the jar with underglazes and glazes. Before doing so, always make certain to apply wax resist. Not only should you wax the bottom of your jar, but also all areas where the lid and jar meet. Just as when you wax the bottom, wax a thin “buffer zone”, this time about one-eighth of an inch wide, past the areas where the lid and jar meet on both the interior and exterior surfaces.
The wax resist will help ensure that no underglaze or glaze material will weld your lid and jar together. However, underglaze and glaze can still bead up on the waxed areas. Make certain to wipe all waxed areas clean as you decorate and glaze.
Tip: As you glaze, also glaze the middle interior of the lid (away from where it meets the jar). This will help avoid tension on the clay body that would occur if only one side were glazed.
Once the decoration and glaze have dried, you are ready to load your glaze kiln. Fire the jar to glaze maturity.