Casting

The majority of Moorcroft’s pottery is made by the casting method. Plaster molds are handmade for each shape. The moulds are filled with slip (liquid clay) and are left to start the drying process. (Casting Movie) Since the plaster is very absorbent, it will start to draw the moisture from the slip. Therefore, the slip will dry from the outside edge inwardly. The longer that the mold is left full, the thicker the body will be.

A piece will be left 3/4 to 2 hours depending on its size. The caster then pours away the surplus slip from the center, leaving a clay lining inside the mold. (Tipping Movie)

Once it’s dry, the caster will run a knife around the top edge of the piece to remove the surplus clay, then remove the piece from the mould. Before the mold is put back together it is thoroughly cleaned as any slip left behind could adhere to the next piece and possibly spoil it. (Mold Removal Movie)

Turning

After spending the night in the drying room, the clay is now firmer and ready to be turned. At this stage there is a basic shape, but the side seams need eliminating along with the surplus clay. The turner uses a foot-controlled electric lathe. The wooden attachment fixed to the lathe is called a chock. Specially designed tools are used for each particular piece. (Turning Movie)

The turner does not use any measuring devices, but relies on his skill and experience to judge the size of a piece, which is one of the reasons that each piece is so individual. The lathe direction is then reversed and a burnishing tool is used to “polish” the outside of the piece. This causes the clay to change color and take on a more refined shape.

Sponging

The clay now needs to be sponged until it is completely smooth. The sponger (fettler) will ensure that each piece is made ready for the decoration, using natural sea sponges to achieve a much smoother finish. (Sponging Movie) The base of the piece is sponged and the first of the factory marks are impressed. There are three marks, the Moorcroft stamp, “Made in Stoke on Trent, England” and a symbol for the year.

Once all the marks have been impressed onto the base, the whole piece will be sponged, checking that the shape is correct, that there are no flaws in the clay, and ensuring that the surface is completely smooth.

It is extremely important that there are no flaws in the clay. At this point, most potteries would biscuit fire the “green ware.” Moorcroft, instead, paints directly onto the clay. They allow the paint to be absorbed into the body to give depth of color.  The only problem with doing this is that if there are any faults in the body, the paint will emphasize them. The piece will then be placed into a controlled damp room to keep the clay at this moist texture while waiting for the tube liner.

Tracing

Tracing is where the decorating process begins. The designer creates individual patterns, tailored for each shape and size within that range. The tracer transfers the design onto clear cellophane using a photocopy of the original. The transfer ink is specially made at the Moorcroft factory. The ink is special because it will remain moist on the cellophane until the tube liner is ready to transfer the outline onto the clay. In addition, once the decoration is complete if there is any ink remaining on the clay, it will burn off when fired in the kiln. (Tracing Movie)

The red marks on the tracings are simply guidelines to help the tube liner position the drawing correctly when transferring the design. There may be three or four different drawings used make up the design, creating a type of jigsaw puzzle.

Tube Lining

The tube liner transfers the tracing on the clay, matching all of the red markings to ensure that the drawing is correctly positioned, then rubs the cellophane with the fingertips leaving the design outline on the piece. (Transfer Movie)

The tube liner uses a rubber bag filled with liquid clay (slip) to slip trail the outline of the design. The rubber bag is held in the palm of the hand, and by applying pressure to the bag the slip is forced through the glass tube. The more pressure applied, the heavier the tubing line will be. It is very important that the pressure be kept constant and even. The joins between two pieces of tube lining need to smooth and strong. The painting technique used is predominantly a flowing technique. Paint will be washed into those defined areas. If there are any gaps in the tube lining, the paint would escape into the surrounding area. (Tube Lining Movie)

It takes 12 to 18 months to train a tube liner. The time it takes to tube line a piece  can vary from 10 to 15 minutes for a small simple piece up to 9 or 10 hours for a large Limited Edition. Using her own brass stamp, the tube liner will stamp her initials on the base of the piece alongside the factory marks. This adds a personal element because some Moorcroft collectors enjoy finding out as much as possible about their individual pieces.

Once the piece is complete it is placed in a controlled drying room overnight. By drying the clay body it is made very absorbent, allowing the paint to soak directly into the clay to achieve those deep rich colors.   

Painting

The painter mixes powdered metal oxide paint with either gum arabic or benitite. This gives the paint its thick consistency. Water is added to achieve the strength of color needed. This illustrates how two pieces of the same design can be noticeably different.

The designer puts all the colors down on paper and the painters have samples to refer to. They are allowed some leeway because many of the colors at this stage bear little resemblance to those seen on the finished piece. 

The painting technique is known as “floating.”  As much paint as possible is loaded onto the paintbrush, then the brush is guided over the surface of the clay, allowing it to float within the tube-lined areas. By tilting the pot, the artist guides paint to flow in the direction wanted, using the brush to absorb any excess paint. (Painting Movie)

Although the paint is very watery, it is possible to see how quickly it is absorbed into the body of the clay, drying almost immediately.  An important part of the painting is how the artists use their hands and fingertips to blend the colors, producing the shade and tone. The artist can build up layers of paint to create the desired depth of color. Often, two or three different paints are blended to make a specific color. During the firing, the lower colors put on first will burn through to the surface.  So the painter is actually mixing the paint on the pot. Compare the colors in the two before-and-after photos at left.

As with the tube liners, there is a 12 to 18 month training period for our painters. Each painter is responsible for the whole piece from start to finish. Once the piece is complete the painter will highlight the factory marks with a wash of color and paint their own initials on the base of the piece.

Biscuit Firing/Selection

The decorated pieces are carefully placed onto a truck. (Placing Movie). When the truck is full, it is wheeled into an electric-powered biscuit kiln. It takes approximately 8 hours with the kiln reaching temperatures of up to 1100 degrees centigrade.  Once the firing is complete, the ducts at the top of the kiln will start the cooling process. When the biscuit firing is complete, the shapes of the pieces are now rigid and set.  Also, the colors applied by the painters are now permanent. However, the finished color is only achieved during the final firing.

At this point, the pieces are selected formally for the first time. This is called the “biscuit selection.”  The biscuit selectors will take each piece from the truck and check it for any damage done during the firing. They will also check that the painter and tube liner haven't missed anything. Once the piece has been selected, the final marks are painted onto the base - the factory monogram, WM, and the copyright mark. The date at the side is the date that the design was put on paper. If the piece is a Limited or Numbered Edition, it is marked accordingly.  There are certain important pieces which warrant a full signature. In this instance, the designer will sign the base.

Dipping & Glost Firing

Once the piece has been biscuit fired, it needs a coating of glaze. Moorcroft uses a clear, transparent glaze.  They use no colored glazes at all.  A glaze is the raw ingredient of glass, ground to a powder and then held in a liquid suspension.

The dipper relies on his experience to make sure the glaze is of the right consistency by dipping his hands into the glaze. Each piece is lowered into the glaze. Because the body is very porous, it immediately starts to absorb moisture, leaving the glaze on the surface of the pot. The longer the piece is left in the glaze the more it will take on, so each piece will be dipped for only a few seconds. The dipped pieces are then placed on to a board to dry overnight. (Glazing Movie)

The following morning each piece will be checked, the base cleaned with wet felt pads, and the piece placed directly on to the shelf of the kiln truck. Each piece is checked to be sure that the glaze is completely smooth. Once each piece has been checked it is ready to be glost fired.

Each piece is placed with great care onto the glost truck ensuring that no two pieces are too close together. During the firing, the coating of glaze, which has now hidden all of those colors, will melt and set again as clear glass, a process known as vitrifying. As it does so, it has a tendency to expand, therefore if two pieces were a little too close they could easily fuse together. (Glost Firing Movie)

Once full, the truck will be wheeled into the center kiln. It will again take approximately 8 hrs reaching roughly the same temperature as the biscuit firing (1100oC) at its peak.  During the firing there is chemical reaction between the clay, the paint and the glaze. The lower colors will burn through to the surface and the true colors will be revealed for the first time. This is called the main color status change. The kiln is then allowed to cool and once the truck has been wheeled out, the decorators will see their beautiful finished pieces.