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Making china is very
much like making a cake. First you decide what type of cake you want and then
you gather the ingredients in the right proportions, blend them carefully,
and finally bake for the appropriate length of time at the correct
temperature. Ernest knew that he wanted to make china that was thin,
translucent and strong, that would give the satisfaction in everyday use that
comes with a well designed, quality product. Having decided what he wanted to
make he then experimented with the ingredients, temperature and cooking time
until he reached the unique recipe that is still in use today.
Branksome China products are formed using plaster moulds taken from our own, original designs. The original model is sculpted from plaster, this is then used to make a mould. The mould taken from the original is known as a block. Hardwearing dental plaster is then poured into the block to form a copy of the original, this is known as a case, the moulds that we use in the factory are made from the case. When new moulds are required we take a case and soak it in water to ensure that trapped air is removed and won’t be released into the new moulds causing bubbles. It is then sized, using soft soap, to prevent the plaster from sticking. If the mould is to be used on a machine it is formed by placing a metal ring onto the case, when plaster is poured into this ring it forms the face of the mould from the case and a foot, to fit the machine, from the metal ring. A metal ring for a saucer mould can be seen at the bottom right of this picture, next to it is a metal cottle that forms the outside foot of the beaker mould just behind it. All other moulds are formed by tying a cottle of either wood or vinyl around the case into which the plaster is poured. A frog mould is being sized on the left of this picture, beside another cottled in vinyl.
Once the wet plaster is poured into the cottle it is vibrated to release any trapped air, again to prevent bubbles forming. When the plaster has set the cottle is removed and the mould is left to dry completely before it is used. Round plates, saucers and bowls are made, by Sara, on the plate machine. This machine has two arms which are raised and lowered automatically. A slice of clay sausage is placed onto the wheel on the right of the machine, the arm lowers and the attached tool flattens the sausage to the necessary width. Sara transfers this clay pancake to the mould that she has placed in the spinning base on the left. The interchangeable tools attached to this arm form the backs of the items she makes and press the clay onto the face of the mould to form the front. This process is carried out simultaneously so there is always a pancake forming as a plate is being made. In this picture Sara is trimming the excess clay from the side of the saucer that she is making as a pancake is being formed to her right. On the tray to the left of the picture are two formed saucers and an empty mould. Behind her are the trays of moulds used to form various plates, bowls and saucers.
As each tray is filled it is placed in racks in the centre of the factory where the clay saucers dry in the air, they are then lifted from the moulds and placed in stacks of 6 to await fettling. At this stage the clay is very brittle and easily broken but, like the trimmings of wet clay, any dry scrap can be put back into the mix and reused. Sara places the dried clay items onto a wheel and carefully removes the ragged excess of clay from around the side, taking it back to the edge of the plate that has been formed by the mould. Once fettled the items are gently sponged to ensure there are no sharp edges and then stacked on trays to be loaded in to the kiln and fired. Cups and plates are fettled in much the same way, using a sharp blade that is held gently against the spinning item, as in this picture of a cup being fettled on the lathe.
The cup machine has a manually operated arm and its base is operated by a touch sensitive switch that Jenny works with her thigh. The pressure applied determines the speed at which the wheel turns. This process is known as jollying. Jenny places a slice of clay sausage into the mould and the pressure from the appropriate tool causes the clay to rise up the inside of the mould as it spins in the metal base. The mould forms the out side of the item as the tool forms the inside, each tool is set to ensure the thickness of each item is constant. In this picture the excess clay is being trimmed from the top of the mould and behind the machine are moulds for making egg cups, and other hollowware items.
Unlike the plates the cups must not dry in the moulds as their handles need to be attached while they are still moist. They are left until the porous plaster of the mould has absorbed enough moisture from the clay to allow the item to slip from the mould when it is upended. While the cups are in their moulds Jenny goes upstairs and fills the handle moulds with slip, our clay mixture added to water to give it a fluid consistency. She then takes the cups from their moulds and using a lathe fettles them, next she sponges them, still moist, to remove any sharp edges. After an hour the slip in the handle moulds is sufficiently hardened to allow Jenny to remove and trim them to the shape of the outside of the cup, using a purpose made guillotine. She takes the handles to the cups and sticks them together with sticking up slip, our clay body with extra ball clay to give it a stickier consistency. This picture shows tea cup handles in their mould, ready to lift out. Beside them are handles that have been cut using the guillotines on the back of the bench.
The finished clay cups are then boxed together, stuck rim to rim with a vegetable based glue to ensure that they keep their shape while firing, this glue evaporates in the kiln, unlike the sticking up slip which bonds the handle to the cup in the heat. More detailed items and those that can’t be made on the machines are made upstairs using slip which is poured into the moulds. Moulds are filled with slip and then left to allow the porous plaster of the moulds to absorb the moisture from the slip which is touching the sides. The slip that isn’t touching the mould remains runny and is poured from the moulds, at a time carefully calculated to guarantee the correct thickness. Times differ according to the size and required thickness of each item. Detailed moulds are marked using a 5 bar gate system and destroyed after 50 usings, to be replaced with new moulds, this keeps the detail crisp on every item. Some items, tea pots and some animals for example, are made in several moulds and are fitted together with sticking up slip while moist. All items are then fettled and sponged before being fired in the first, biscuit, kiln. In this picture Priscilla is taking a sea horse from its mould, On the bench beside her are moulds for the water lily bowls which are drying out between pourings. Moulds for other slip cast items are stacked in the racks behind her.
Once the clay items have been fettled and sponged they are ready to be fired for the first time, this turns the ware from brittle clay into hard, translucent porcelain. The first firing of the ware is known as the biscuit firing, as once the clay has been fired it becomes translucent biscuit ware, our body is quite different in that our biscuit ware is non- porous. Clay plates are put into setters to help them keep their shape while firing and these setters are stacked to fill the kiln. Hollowware items are fired in a separate kiln and are loaded in layers on batts again to fill the kiln, as in this picture.
Both flat and hollowware items are built up on trucks which are then wheeled into the cool kiln. In both cases the kiln is fired to 1300 degrees C which takes between 9 and 10 hours. The insulation in the kiln ensures that the factory doesn’t heat up as the kiln is firing and the kiln’s thermostat switches the power off as soon as the required temperature is reached. After about 12 hours the kiln has cooled to around 400 degrees C, which is cool enough to open it. When Ernest developed the body he knew that he could make a high fired porcelain that was more durable and he had to overcome many obstacles in manufacture to achieve this, pushing the tolerance of the materials to the limit, for more details go to The History of Branksome China. All items shrink by 10% in the first firing, this means that the items can touch each other in the hollowware kiln as they shrink away from each other as they cook. The difference in size can be seen in this picture, the boxed clay cups on the left are ready to go into the kiln and the biscuit ware cups on the right have just come out of a fired kiln.
After firing the kiln is unloaded and the items sorted, anything that has twisted or cracked in the kiln is broken and thrown away. Once sorted every item is stamped with our name, using ink that we make, then taken to be hand painted or sprayed. Hand painting is done directly onto the biscuit ware. To ensure our patterns match in size and position from piece to piece we use pounces. Pounces are created from our original designs. When we are happy with the look of a design created by our artists it is fired, and from this original a tracing is made onto greaseproof paper. The out line of the design is pricked through the paper, this pricked through tracing is the pounce, which can be used for years to come. Pounces, as required, are then placed onto biscuit ware items and tapped with a bag of charcoal which leaves a faint impression of the design on the biscuit ware. Carol and Priscilla use this as a guide to the position of the pattern, painting in detail over the charcoal. Charcoal disappears in the intense heat of the kiln. Pounces are used to ensure that patterns stay consistent, however they are not detailed and each hand painted item is totally unique, unlike china which is decorated using stencils or transfers. The hand painting colours are made by Jonathan to a recipe that is compatible with our body. When an item has been painted it is sprayed with a transparent glaze, before being fired for the second time. This method of under glaze painting means that the painting will never fade and even when used daily in dishwashers and ovens it will always retain the crispness and vibrancy of the day it was bought. Carol and Pris add any personal messages to items at this stage, so a message of congratulations for a wedding, for example, will also be permanent, and will never fade.
Figure and animal studies are decorated using a combination of hand painting and spraying. Each item differs in the methods used to decorate it. In each case the fine detail is filled in with brushes and paints similar to those used in hand painting. In the case of the seahorse in this picture the sea weed on the base, and the eyes are painted using a brush. The base is sponged with blue which is rubbed away to leave the detailing in the model more visible before being sponged in green. The seahorse is sprayed from the top to the bottom using an amber under glaze colour, then from bottom to top with purple, this creates the two tone effect. Detail on the edge of the fin is picked out in black and finally the whole model is sprayed in a transparent glaze before being fired for a second time.
Branksome China is glazed with glazes that Ernest invented to be compatible with our body, to ensure they don’t craze. All of our glazes are made in the factory, Jonathan grinds the colour pigment and adds this to the glaze which is then sieved and weighed, to ensure the correct water content. As our biscuit ware is non porous the finished glaze is also tested for viscosity to make sure that it will not run off the items as they are sprayed. It is then taken to Trish to be sprayed onto the biscuit ware. A vegetable dye is added to the lighter glazes to allow Trish to see more easily which areas of an item she has covered. Items are sprayed on both sides separately. Trish fills her spray gun with the appropriate glaze and sprays all items that are required in that colour. These are then left in racks to dry while Trish washes out the spray gun and changes glazes. The other sides of the items are sprayed only when the first glaze is dry enough to allow Trish to pick it up without leaving fingerprints. The only exception to this are tea and coffee pots, they are glazed inside by filling them with glaze which is then poured out. This method of pouring ensures that all areas inside the pots get an even covering of glaze and therefore don’t stain. In this picture Trish is spraying the inside of a shell, the light green glaze becomes a translucent aqua colour when fired.
After the items have been sprayed they go into the kiln for a second firing. The second, glaze, kiln is a mixture of flat and hollowware. Unlike the biscuit kiln it is important to place the items with space around them. Items don’t shrink any further in this kiln but the glaze melts in the heat and if items are touching they can become stuck together. It is also important that items are stood on pins or have their bases wiped before going into the kiln to prevent them sticking to the batts when firing. This kiln is fired to 1200 degrees C, at this temperature the glaze melts and bonds with the biscuit ware, changing from a dry powder to shiny glass. As with the biscuit kiln the thermostat turns the kiln off when it reaches temperature and the kiln can be opened at 400 degrees C. In this picture Pris is pushing a loaded glaze truck into the kiln. The items that are covered in glaze, coloured blue with the vegetable dye, will be a riot of colours and hand painted items when they are pulled out the next day. To the right of the picture you can see a half loaded, flat ,biscuit ware kiln , between each of the setters is a soft clay plate. This truck will be pushed in when the glaze kiln has been pulled out.
After the glaze kiln has been unloaded any, tiny, sharp areas on the base, where the glaze has melted around the pins, are removed with a hand held compressed air grinder. They are then checked and any items with slight faults are sold in our factory shop as seconds. As all of our items are hand made there are sometimes slight variations in finish, we feel that this adds to their appeal as unique, hand made items and is testament to the extremes of tolerance that the materials are placed under during our unique manufacturing process, which results in porcelain which is so delicate to feel yet so strong in use. We hope that this has given you some insight into the processes that go into making Branksome China. We are happy to answer any questions that you may have to the best of our ability and if you are ever in the area why not drop in and allow us to take you on a guided tour of the factory in person.
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