Ceramic Art Trends, Tools, and Techniques for Potters Worldwide

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Pottery Forming Techniques

Basic Wheel-throwing Steps

1. Start off with clay of the proper consistency: soft enough to throw easily, yet not so soft that it will quickly collapse. Clay that's too hard or dry is very difficult to throw. Be sure to wedge the clay carefully up to 100 times, taking care not to fold it in a way that might trap air bubbles within. Mold into as perfect a cone shape as possible, and smooth out all cracks.

2. Slam cone onto the center of the wheelhead or bat. Slowly spin the wheel to see if clay is off center; if so, gently slide cone toward the center as much as possible while the wheel is turned off.

3. Thoroughly wet the clay and start wheel turning to begin centering process. Cup hands evenly around clay and force cone upward and downward a few times to align the clay particles. Then firmly press inward with one hand, and downward with the other, making sure the entire exterior surface of the clay hump is in contact with a portion of the hands. Keep hands firmly positioned in one spot, and with wheel spinning rapidly, steadily maintain that position until the clay offers no resistance, periodically wetting it as necessary. Whenever you remove your hands from the clay, be sure to do so SLOWLY, so as not to knock the piece off center.

4. Once the clay is centered, cup hands around it and allow thumbs to glide into center while wheel is turning. Press slightly to make dimple, or impression, in the middle. With both thumbs or one of forefingers, steadily press downward in center to make a hole in the clay that's roughly 1/2 to 1/4 in. from the bottom. Periodically stop the wheel and check the depth by poking through the floor of the pot with a needle tool until the desired thickness is reached.

5. Now use forefingers or thumbs (whatever's more comfortable) to open floor of pot outward, being sure to slide fingers across the clay STEADILY, at the same level as the desired thickness of the floor of the pot. Continue to open the clay outward until the inside diameter of the pot is roughly 10% wider than the desired inside diameter of the finished piece, to plan for shrinkage.

6. Begin to pull clay upward with fingers or knuckles of both hands, one on the outside, the other inside. First undercut the bottom edge of the pot with outside fingertip to form a clay ledge. (Always make sure to re-set the rim of the pot after each movement, to keep it on center.) With fingers of inside hand slightly higher than those on the outside, and outside fingers (or knuckle) positioned underneath the clay ledge, gently squeeze the clay between the fingers at an even pressure, and steadily pull upward at the same rate the wheel is revolving. (At this stage, the wheel should revolve at a medium to slow speed.)

7. Repeat the process until the clay walls have reached an even thickness and desired height. If you accidentally knock the clay off center or end up with walls that are uneven, try this: apply a straight-edge wooden rib to the outside of the pot, and hold your left forefinger at a 90 degree angle, pointed downward, on the inside of the pot. Slowly spin the wheel and force the wall of clay between the inside forefinger and outside straight edge back into a uniform thickness, slowly and steadily gliding upward until entire wall is uniform.

8. Gently shape the pot with fingers or ribs, re-set the rim, and release from the bat with a wire or string cutter.

How to Make Different Types of Lids

The making of lids for different types of pots is not as difficult as one might expect. With a little bit of practice and a good set of calipers, this skill is relatively simple to master.

A domed lid thrown upside down is designed to rest on an indentation, or gallery, carved into the rim of the lid's partner pot during the final stage of throwing. To make the indentation in the supporting pot, one should start with an extra-thick lip. After the pot has been pulled up, shaped and thinned to its desired size, simply press downward and inward on the inside of the lip with the thumb at a right angle.

As soon as the gallery has been made, use a set of potter's calipers to measure its diameter while the pot is slowly spinning on the wheel. Be sure to get an exact measurement of the interior edge of the gallery where the lip of the lid is to fit, before the pot begins to dry and shrink.

To make the lid, throw a bowl directly on the bat or off the hump, but first make an indentation beneath the solid ball of clay for a stem to be trimmed into a knob. (Another option is to throw the bowl with a flat base, then add a knob when the pot is leather-hard.) As you throw, check the size of the pot's diameter with calipers and adjust by cutting away clay or pulling the clay up or down until the desired size is reached.

At first, it's usually best to make two or three lids per pot to be sure you'll have one that fits the supporting pot. It's also a good idea to make the lip edge of the lid sharply pointed to assure that it will rest level on the supporting pot.

A domed lid thrown right side up is a bit harder to throw, yet requires no trimming. This type of lid also rests on a gallery, and is well-suited to larger companion pots which need a tall curve to enhance their shape.

Start this type of lid by opening a "donut" of clay to the desired diameter and cutting away excess clay from the interior bottom edge with a ribbon trimming tool. Next, pull up the walls of the dome to the desired height and thickness. Squeeze inward, then outward, at the top to shape a hollow knob. Cone in and narrow the stem of the knob to a nearly closed position, and add a ball of clay inside to close up the hole. Cut off the bat and trim a clean edge when the pot is leather-hard.

A flanged lid is made to fit a pot with a standard lip (no gallery). First use calipers to measure the exterior of the supporting pot's lip. Next, center a ball of clay with a diameter that equals the caliper measurement. Open the clay without expanding the diameter, and push the clay inward and upward with the fingertips to make the interior wall (or flange). Shape the underside of the lid slightly upward for a domed effect, or leave flat if you wish. Re-measure the outside edge and interior flange of the lid to be sure they'll fit the supporting pot, adjusting if necessary. Then cut off the lid and trim right-side up when leather-hard. If you like, a knob may be attached by throwing directly on top of the lid (very carefully) or by pre-throwing and scoring the knob, then attaching with thick slip.

Making Your Own Press Molds

Handbuilding of similar items is easily accomplished with the use of press molds of various shapes and sizes. But you needn't purchase them ­ it's relatively easy and much more affordable to learn a few simple steps toward making your own mold.

By far the easiest method is to make your large, rounded molds by throwing them on the potter's wheel, then firing to bisque at cone 010 for molds that are sturdy, yet porous and absorbent enough to release your hand-built forms as they dry. The molds should be at least 1/2 in. thick, however, to absorb moisture sufficiently. This technique may be used to make as many molds as you wish, in any size you're physically able to throw or build and fit into your kiln. In case of eventual breakage, it's a good idea to make at least two molds of each shape/size so that you have a back-up handy for last-minute projects, in case of breakage.

To make a plaster mold, you'll need pottery plaster from your local supplier or a bag of plaster of paris (from the hardware store), water, a large bucket for mixing, a jar of Vaseline, a flexible rib, and the form to mold, or "model."

Start by placing the model on a flat, clean surface, and setting a clay coil around it, roughly 1/2 in. from the form. Next, apply a heavy coat of Vaseline to the mold, the table surface, and the coil. Mix the powdered plaster with water as instructed on the plaster bag and stir thoroughly, then apply to the model and coil when creamy, at a thickness of at least 1/2 inch. Do not allow the plaster to extend beyond the clay coil. As the plaster sets, scrape it smooth with a flexible rib. Once it has hardened and dried (usually about 30 minutes or so), it can be removed from the model and coil, and sanded on both sides. Let set for about 24 to 48 hours to fully dry. The interior may now be used as a "slump" mold; the exterior, as a "hump" mold. The ridge left by the clay coil offers a useful ledge for lifting the mold. To use the mold, drape with a soft clay slab, then remove the slab when leather hard; trim, decorate, and fire as usual. Be careful, however, not to let any plaster chips remain in the clay, as they will cause large pop-outs during firing. When cleaning up, let plaster dry and put in the garbage ­ don't rinse down the drain, or it will clog the pipes.

Making Terrific Teapots

A fairly advanced form when compared with most pottery projects, the teapot poses a variety of challenges that can be successfully achieved by careful thought and planning during the design stage.

One must first decide what sort of teapot to make. This will depend mostly on personal preference and intended use. It's important to note that regardless of how your teapot will eventually look, it will not function as a tea kettle ­ that is, it won't be available for use directly on the stovetop burner ­ unless it is made of flameware clay and glazed with an appropriate flameware glaze. Otherwise, the pot will explode. Because flameware contains a high content of petalite, an expensive ingredient, and must be fired to at least cone 10 or higher, most teapots are made of stoneware and should only be used for steeping and serving tea. Teapots made entirely of clay (handle included) and which fit into a microwave oven may offer an alternative form of heating the tea water.

A teapot is usually made up of four parts: the body, the lid, the spout, and the handle.

The Body

Usually the simplest yet most influential part of the teapot design, the body may be completely round, oval, or even paddled into a square or octagonal form. The size should depend on the intended function of the pot. If it's a one-person or two-person pot, it should be capable of holding anywhere from two to four cups of liquid. A teapot designed to serve a larger number of people should hold at least one cup of liquid per person to be served. Matching teacups should each hold 6 to 8 ounces of liquid for practical daily use; traditional Japanese sets usually hold considerably less.

When making the body, be sure to recess the lip into a gallery wide enough to comfortably accommodate the lip of the intended lid. Then measure the opening with calipers as the wheel turns slowly to gauge the diameter of the lid to be made. For practical daily use, the opening of the pot itself should be wide enough to accommodate the user's hand and a sponge for washing.

The Lid

The lid of your teapot can be either convex (domed) or concave (recessed), depending upon the overall design effect you wish to achieve. A concave lid is most functional, especially if made somewhat thick and heavy, because it is less likely to fall off the pot when it's tilted for pouring out the tea. A convex lid, however, can offer a much more elegant look, continuing the curved profile of the pot upward and completing the look with a decorative knob.

The knob is essential for removing and replacing the lid, yet its shape can be as basic or ornate as you wish. If you sell your teapots, you might recommend that customers hold the knob of the lid while pouring out the tea so the lid doesn't topple off unexpectedly. If you wish to prevent this occurrence, add a locking mechanism to your lid ­ a little clay hook off the inside bottom edge ­ and a notch in the gallery of the pot where the "hook" may be inserted and rotated to lock the lid into place.

When the lid is leather-hard, be sure to drill a hole about half-way between the knob and the outer lip of the lid so air can enter the pot and help force tea through the spout for smooth pouring.

The Spout

The spout can be made by throwing a funnel-shaped cylinder on the wheel, making the walls at a thickness consistent with the walls of your teapot. This will promote even drying and discourage the spout from cracking off after it's been attached.

While throwing the spout to the form of your liking, be sure to make it long enough so the lip of the small end extends higher than the lip of the lid gallery after attachment to the body. Otherwise, the teapot will spout out liquid when full, even before it is tilted for pouring. Another consideration in throwing the spout is to smooth out any interior throwing rings before the spout is set aside to dry. This is because the throwing rings inside the spout can channel the liquid into a vortex or spiraling motion, which can interrupt the smooth flow of liquid from the spout. The vortex action may be further inhibited by making a very narrow-ended spout, or by cutting off the end of a wide spout at a about a 35 degree angle.*

When the teapot body and spout are both leather-hard, study the profile of the pot body, and imitate this curve by cutting away a portion of the spout base where it's to be attached, to allow for a smooth fit.

If you wish to feature a built-in strainer in your teapot, mark a circle on the pot where you'll be attaching the spout, and use a metal (somewhat thick) needle tool to poke numerous holes across the entire circle. (To keep these holes from filling up with glaze during the firing process, try filling with wax resist, then sanding off the excess with a green kitchen scrubbing pad before applying the glaze. Be very careful not to let the holes fill up with glaze, or you'll be left with a teapot that doesn't pour! Some potters prefer not to to take this risk, cutting a large hole where the spout is to be attached, and using a regular metal strainer in their tea cups as necessary.)

To attach the spout, score the areas of each piece where they will be joined, and use thick slurry as "glue" for bonding. Smooth out any cracks or rough edges in the join with a wooden knife or sculpting tool.

(*Note: If you find that your spouts tend to rotate during the drying and firing processes, try overcompensating by cutting away the portion of clay from the top of the spout at an angle in the direction opposite the rotation, so the edge of the spout doesn't end up too twisted for pouring.)

The Handle

Your teapot handle can be made in many ways. You can pull one of clay and attach it to the side of the pot, much like a mug or pitcher handle. If you do so, consider attaching to the pot at a comfortable, low level to gain the best leverage for pouring.

An ancient Japanese-style handle is a thrown cylinder formed much like the spout, then attached to the side of the pot. Sometimes an extra handle for two-handed pouring is attached over the spout).

Another type of handle may be made of twisted or "braided" coils of clay, shaped into an arched form, then attached to the top of the pot. If you select this option, be sure to make the arch high enough to allow for easy removal of the teapot lid. For each of the above-mentioned handles, the handle and pot should be joined when equally leather-hard, scored, glued with slurry, covered with plastic wrap, and allowed to dry slowly to prevent cracking.

Many potters also choose to attached non-clay handles, such as Oriental-style pre-shaped cane handles, to small clay loops in the top of the pot. These and other attachable handles are available from most pottery suppliers. Because these handles can be raised up or lowered, they use less vertical space than the fixed clay arch handle, allowing for easier storage of the teapot in a cabinet. To attach this type of handle, first take a measurement of the distance of the opening, and with clay shrink rule, calculate how far apart you'll need to place the loops when forming the pot. Also make sure the clay loops will be large enough for threading the handle after firing. Once the pot has been formed, fired, and glazed to full maturity, attach the handle by soaking it in warm water for about 15-20 minutes to make it flexible, then threading through the clay loops of the teapot. It will resume its original shape upon drying.

Accessories

Along with the teapot itself, one can make matching cups, cream and sugar set, honey pot, and even a serving tray to pull all of the elements of the set together. The style of cups ­ relevant to size, shape, whether or not they feature handles, and how they are decorated ­ is usually based on the teapot itself and how each cup might best enhance or amplify the characteristics of the teapot.

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