A saggar (also misspelled as sagger or segger) is a type of kiln furniture.New Ideas And Proven Solutions For Kiln Furniture Made From Cordierite And Oxide Ceramics. W.Haase & L.Sedda. Ceramic Forum International. Ber.DKG 76, No.7, 1999.Saggar Plants In Tableware Production. G. Sper. Interkeram. 41, No.8, 1989.A.Dodd & D.Murfin. Dictionary Of Ceramics; 3rd ed. The Institute of Minerals. 1994. It is a ceramic boxlike container used in the firing of pottery to enclose or protect ware being fired inside a kiln. The name may be a contraction of the word safeguard.'The Concise Oxford Dictionary of English Etymology'. T.F. Hoad. Oxford University Press. 1996. Retrieved October 14, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-saggar.html
Saggars are still used in the production of ceramics to shield ware from the direct contact of flames and from damage by kiln debris.'Extending The Useful Life Of Saggars'. Karpova N.G., Voitovich V.A. Glass and Ceramics. Vol. 37, No 12. 1980http://amic.biz/Data%20Brochure/AMI%20Kiln%20Furniture%20%28Cordierite-Mullite-Corundum%29.pdf. http://www.ikf-solutions.com/pdf/KF%20for%20TC%20CFI%20April09.pdf.
Traditionally, saggars were made primarily from fireclay.'A Study of the Properties of Saggar Mixtures. Part XVIII: The Use of Fused Silica as Grog in Saggar Mixes.' White R.P, Rigby G.R. British Ceramic Research Association.RP13. 1948'Kiln Furniture Mixes Containing Highly Refractory Grog'. White R.P, Rigby G.R. British Ceramic Research Association. RP161. 1952 Saggars have been used to protect, or safeguard, ware from open flame, smoke, gases and kiln debris:. Modern saggars are made of alumina ceramic, cordierite ceramic, mullite ceramic, silicon carbide'Development Trend Of Dense Alumina Saggar For Electric Materials'. Hayashi K. Ceram. Jap. 38, No.8, 2003. pg.561-563'Silicon Carbide Sagar For Firing Non-oxide Ceramics.' Sakaguchi M., Taskeshita S., Hirota T., Aratani K., Kawakami T. Refractories in the Ceramics Industry. Aachen Proc., 32nd Int.Colloquium on Refractories Aachen, 12–13 October 1989, pg.75-78 Verlag Schmid GmbH and in special cases from zirconia.
The saggars were used for the biscuit and the glost firing. They were expected to last for about 40 firings; each potbank made their own in a saggar making workshop. Saggars were made from fireclay, by a saggar maker and two assistants: the framemaker and the bottom knocker. The framemaker beat the clay into a sheet on a metal table using a large mallet, the mow or mawl. Using a frame he would cut it to size, sprinkle it with sawdust and wrap it around a wooden block to make the walls. The framemaker was usually an apprentice in his late teens. The bottom knocker, usually a boy in his early teens, did the same on a smaller scale, constructing the round or banjo-shaped bottom. Again the mow was used to beat the air out of the clay and flatten the sheet. The saggar maker was an experienced craftsman who paid his assistants out of his piece-work earnings: he took the bottom and the sides onto a wheel and using his thumbs joined the sides to the bottom. The green saggars were dried and then placed on the top of bungs during the next firing of the kiln.
The unfired ceramic ware was placed in saggars on a bed of silica sand or flint dust and then biscuit fired, before being Ceramic glaze and again placed in saggars separated by kiln furniture prior to being glost fired.
A saggar maker's bottom knocker was a job title considered sufficiently amusing for it to be featured on the television panel show What's My Line?. Saggar making Whilst saggar making was a skilled craft, bottom knocking was far less skilled, consisting of beating clay into a metal ring.'Automatic Saggar Handling Plants'. Lippert J., GmBH & Co. Pressath, 1991
Some pots may be carefully prepared for saggar firing. One method creates a smooth surface covered with clay slip, terra sigillata, which responds particularly well to the saggar technique. This slip covering may be burnished to achieve a gloss. Prepared pots are nestled into saggars filled with beds of combustion materials, such as sawdust, less combustible organic materials, salts and metals. These materials ignite or fume during firing, leaving the pot buried in layers of fine ash. Ware produced in filled saggars may display dramatic markings, with colours ranging from distinctive black and white markings to flashes of golds, greens and red tones. Porcelain and stoneware are ideal for displaying the surface patterns obtained through saggar firing. In addition to the use of saggars, some studio potters bundle pots and burnable materials within a heavy wrapping of metal foil.
Studio pottery
Saggar clay
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