George Scatchard Pottery
© 2015 George Scatchard Pottery
website design Wolf Multimedia Studio
POTTER'S CORNER The clay I don't use premixed clay for several reasons. The first is that it is expensive to ship all that water. Water is about 25% of most clay bodies. The second is that I need to knowwhat is in my clay mix to be sure of good thermal properties and glaze fit. The third is that most commercial clay bodies are made with additives that make it run through the mixing machinery more easily in order to save money. I believe that these lubricating additives make a clay much harder to work with because it doesn't stand up well and tends to stretch too easily. My clay mixtures are made from American clays and minerals. I have made a device to test thermal expansion properties of the finished product so I can guarantee oven proof ware for baking. In addition I am able to control the working properties of my clay so it will hold the shapes I am striving to create better than commercially prepared clays. This allows the light well thrown bowls I am known for. I mix my clay in a 20 gallon stainless steel tub with a hand held mortar mixer. I mix the dry ingredients first then add water. I use 100 pounds of dry materials and about 7 gallons of water in each batch. This makes a soft mud that ages nicely in a few days. To dry the clay for use I lay it out on slabs of plaster. To prepare the clay for throwing, I use the kneading technique and fold the clay over and press it together about 100 times to remove any air bubbles and mix it thoroughly. Green Glazing         In the late 1970's, during the first energy crisis I decided to liminate bisque firing from my process. The point was to save time and space. It took a long time to load and fire the bisque and unload the kiln again. We also had to have space to store all the bisque ware. The fuel savings were not as important as the time and space we saved. There are 2 main ways that potters apply glaze to raw clay. The problem is that glaze tends to fall off of the dry clay as it shrinks while drying. One answer is to glaze wet pots so the clay and glaze can shrink together as they dry. This means that each pot has to be glazed when when it is just dry enough to be glazed. That didn't seem practical with the volume of pots I was making. The other method is to glaze dry pots with glaze mixtures that have less water in them to avoid softening the dry clay. By adjusting the clay body to have limited shrinkage and the glazes to contain less water, I was able to successfully make even quite thin ware with almost no losses. This is the system I still use today. The biggest change we made was to eliminate Kaolin from glaze recipes. China clay in general has a huge water requirement. We substitute a ball clay with a very low water requirement. This makes the glaze adhere well and makes the coating much tougher and easy to handle. Ever since the early days, I have done most of my glazing on the wheel. This is a great way to glaze greenware because the pot is unlikely to be broken as it sits on the wheel. Another nice feature of this method is that layers of different glazes can easily be combined for blended effects The kiln        My kiln was built in 1964 to fire the large planters, fountains and garden lights I was making at the time. It is a 100 cubic foot updraft car kiln with two burners that was designed to fire with high pressure propane. These days high pressure propane is not allowed by the local gas companies, so I fire with kerosene. The results are the same as propane, but it is harder to get really good oxidation in the beginning of the firing. I am using home made burners with siphon type air atomizing nozzles like those used for waste oil systems. This system uses air pressure to atomize the kerosene and requires a good size compressor to provide the air. This type of system can also work with waste oil, diesel fuel, heating oil or vegetable oil. I use kerosene because it doesn't get as thick in the Winter.
George Scatchard Pottery
© 2015 George Scatchard Pottery
website design Wolf Multimedia Studio
POTTER'S CORNER The clay I don't use premixed clay for several reasons. The first is that it is expensive to ship all that water. Water is about 25% of most clay bodies. The second is that I need to knowwhat is in my clay mix to be sure of good thermal properties and glaze fit. The third is that most commercial clay bodies are made with additives that make it run through the mixing machinery more easily in order to save money. I believe that these lubricating additives make a clay much harder to work with because it doesn't stand up well and tends to stretch too easily. My clay mixtures are made from American clays and minerals. I have made a device to test thermal expansion properties of the finished product so I can guarantee oven proof ware for baking. In addition I am able to control the working properties of my clay so it will hold the shapes I am striving to create better than commercially prepared clays. This allows the light well thrown bowls I am known for. I mix my clay in a 20 gallon stainless steel tub with a hand held mortar mixer. I mix the dry ingredients first then add water. I use 100 pounds of dry materials and about 7 gallons of water in each batch. This makes a soft mud that ages nicely in a few days. To dry the clay for use I lay it out on slabs of plaster. To prepare the clay for throwing, I use the kneading technique and fold the clay over and press it together about 100 times to remove any air bubbles and mix it thoroughly. Green Glazing         In the late 1970's, during the first energy crisis I decided to liminate bisque firing from my process. The point was to save time and space. It took a long time to load and fire the bisque and unload the kiln again. We also had to have space to store all the bisque ware. The fuel savings were not as important as the time and space we saved. There are 2 main ways that potters apply glaze to raw clay. The problem is that glaze tends to fall off of the dry clay as it shrinks while drying. One answer is to glaze wet pots so the clay and glaze can shrink together as they dry. This means that each pot has to be glazed when when it is just dry enough to be glazed. That didn't seem practical with the volume of pots I was making. The other method is to glaze dry pots with glaze mixtures that have less water in them to avoid softening the dry clay. By adjusting the clay body to have limited shrinkage and the glazes to contain less water, I was able to successfully make even quite thin ware with almost no losses. This is the system I still use today. The biggest change we made was to eliminate Kaolin from glaze recipes. China clay in general has a huge water requirement. We substitute a ball clay with a very low water requirement. This makes the glaze adhere well and makes the coating much tougher and easy to handle. Ever since the early days, I have done most of my glazing on the wheel. This is a great way to glaze greenware because the pot is unlikely to be broken as it sits on the wheel. Another nice feature of this method is that layers of different glazes can easily be combined for blended effects The kiln        My kiln was built in 1964 to fire the large planters, fountains and garden lights I was making at the time. It is a 100 cubic foot updraft car kiln with two burners that was designed to fire with high pressure propane. These days high pressure propane is not allowed by the local gas companies, so I fire with kerosene. The results are the same as propane, but it is harder to get really good oxidation in the beginning of the firing. I am using home made burners with siphon type air atomizing nozzles like those used for waste oil systems. This system uses air pressure to atomize the kerosene and requires a good size compressor to provide the air. This type of system can also work with waste oil, diesel fuel, heating oil or vegetable oil. I use kerosene because it doesn't get as thick in the Winter.