| Pottery can be shaped by a range techniques, | | | | technique, jolleying, refers to the |
| including: | | | | production of holloware like cups. These |
| | | | techniques have been in use since at least |
| Handwork can be considered both the most | | | | the 18th century Partial automation of the |
| primitive and the most individualized | | | | jiggering and jolleying processes have long |
| techniques, where pieces are constructed from | | | | been used to increased production rates and |
| hand-rolled coils, slabs, ropes, and balls of | | | | de-skill the operation |
| clay body, often joined with a slurry of clay | | | | |
| body, known as slip. No two pieces of | | | | Roller-head Machine A machine for the shaping |
| handwork will be exactly the same, so it is | | | | of pottery flatware on a rotating mould, as |
| not suitable for making precisely matched | | | | in a jigger, but with a rotary shaping tool |
| sets of items such as dinnerware. Doing | | | | instead of a fixed profile. The rotary tool |
| handwork enables the potters to use their | | | | is in the form of a shallow cone of the same |
| imagination to create one-of-a-kind works of | | | | diameter as the ware and shaped to produce |
| art. These methods are often referred to as | | | | the back of the article being made. The ware |
| "handbuilding". | | | | is completely shaped, by relatively unskilled |
| | | | labour, in one operation at a rate depending |
| Classic potter's wheel in Erfurt, Germany.The | | | | on the size of the ware of about 12 pieces |
| potter's wheel. A ball of clay body is placed | | | | per minute. The machine, developed from |
| in the center of a turntable, called the | | | | earlier attempts to improve on the use of a |
| wheel head, which is turned either using foot | | | | fixed tool, was patented by T. G. Green & Co. |
| power (a kick wheel or treadle wheel) or a | | | | and H. J. Smith (Brit. Pat., 621 712, 14/4 |
| variable speed electric motor. Oftentimes, a | | | | 49) with subsequent improvements by J. A. |
| bat (a disk of plastic, wood, or plaster) is | | | | Johnson (Brit. Pat., 765 097, 2/1/57; 895 |
| affixed to the wheel head, and the ball of | | | | 988, 9/5/62). It is now widely used across |
| clay body is attached to the bat rather than | | | | the world |
| the wheel head so that the finished piece can | | | | |
| be removed easily without distorting the | | | | Ram Pressing A process for the plastic |
| piece. The wheel is made to revolve rapidly | | | | shaping of tableware and sanitaryware by |
| while the body is pressed, squeezed, and | | | | pressing a bat of the prepared body between |
| pulled gently into shape. The process of | | | | two porous plates or mould units; after the |
| pressuring the body into a rotational | | | | pressing operation, air is blown through the |
| symmetry, so that it does not move from side | | | | porous mould parts to release the shaped |
| to side as the wheel head rotates is referred | | | | ware. Although the process was patented in |
| to as "centering" the body — a most | | | | 1952 by Ram Incorporated, US Pats, 2 584 109 |
| important skill to master before the next | | | | & 10, the term is often used for similar type |
| steps, "throwing" (forming and raising the | | | | shaping processes |
| walls of the piece) and "trimming" or | | | | |
| "turning" (removing excess clay to refine the | | | | Granulate pressing This involves the shaping |
| shape or create a bottom or foot can be | | | | of ware by compressing semi-dry and |
| taken. | | | | granulated body in a die, one side of which |
| | | | is a solid surface and the other a flexible |
| Potter's wheels can be used for mass | | | | membrane through which fluid pressure, of up |
| production, although often it is employed to | | | | to 100 MN.m-2, is transferred. The granulate |
| make individual pieces. Wheel work takes a | | | | is produced by spray drying to give a fine |
| lot of technical ability, but a skilled | | | | and free flowing material with a low moisture |
| potter can produce many virtually identical | | | | content of around 5-6%. Also known as dust |
| plates, vases, or bowls in a day. Because of | | | | pressing the technique is widely used in |
| its nature, wheel work can only be used to | | | | manufacture of wall and floor tiles, and |
| initially create items with radial symmetry | | | | increasingly of plates |
| on a vertical axis. These pieces can then be | | | | |
| altered by impressing, bulging, carving, | | | | Turning is similar to that used for the |
| fluting, faceting, incising, and other | | | | shaping of metal and wood articles. A blank |
| methods to make them more visually | | | | of clay body, with low water content in a |
| interesting. Often, thrown pieces are further | | | | condition known as leatherhard, is mounted on |
| modified by having handles, lids, feet, | | | | a lathe whilst a cutting tool follows a |
| spouts, and other functional aspects added | | | | profile to removes excess material and hence |
| using the techniques of handworking. Pottery | | | | leave a shaped article |
| that is thrown on the wheel is often finished | | | | |
| in a process known as trimming. | | | | Slipcasting is a technique often used for |
| | | | mass-production, and ideally suits shapes |
| Jiggering & jolleying These can be seen to be | | | | that can not be made by other methods. Liquid |
| an extension of using a Potters wheel, and in | | | | clay body slip is poured into plaster moulds, |
| comparison allow increased speed and improved | | | | the permeability of the mould drawing water |
| repeatability. Jiggering is the technique | | | | from the slip to leave a layer the clay body |
| where a shaped tool is slowly brought down | | | | of the internal shape of the mould. This |
| onto plastic clay body that has been placed | | | | method is almost universally used for |
| on top of a rotating plaster mould. The | | | | sanitaryware, toilets and wash basins, as |
| jigger tool shapes one face whilst the mould | | | | well being widely used for smaller pieces |
| the other. Jiggering is the term specific to | | | | such as figurines which have many intricate |
| flatware such as plates whilst a similar | | | | details. |