Repoussé and chasing
Encyclopedia
Repoussé or repoussage ʁəpusaʒ is a metalworking
Metalworking
Metalworking is the process of working with metals to create individual parts, assemblies, or large scale structures. The term covers a wide range of work from large ships and bridges to precise engine parts and delicate jewelry. It therefore includes a correspondingly wide range of skills,...

 technique in which a malleable metal
Metal
A metal , is an element, compound, or alloy that is a good conductor of both electricity and heat. Metals are usually malleable and shiny, that is they reflect most of incident light...

 is ornamented or shaped by hammer
Hammer
A hammer is a tool meant to deliver an impact to an object. The most common uses are for driving nails, fitting parts, forging metal and breaking up objects. Hammers are often designed for a specific purpose, and vary widely in their shape and structure. The usual features are a handle and a head,...

ing from the reverse side to create a design in low relief. There are few techniques that offer such diversity of expression while still being relatively economical. Chasing is the opposite technique to repoussé, and the two are used in conjunction to create a finished piece. It is also known as embossing.

While repoussé is used to work on the reverse of the metal to form a raised design on the front, chasing is used to refine the design on the front of the work by sinking the metal. The term chasing is derived from the noun "chase", which refers to a groove, furrow, channel or indentation. The adjectival form is "chased work".

The techniques of repoussé and chasing utilise the plasticity
Plasticity (physics)
In physics and materials science, plasticity describes the deformation of a material undergoing non-reversible changes of shape in response to applied forces. For example, a solid piece of metal being bent or pounded into a new shape displays plasticity as permanent changes occur within the...

 of metal, forming shapes by degrees. There is no loss of metal in the process, as it is stretched locally and the surface remains continuous. The process is relatively slow, but a maximum of form is achieved, with one continuous surface of sheet metal of essentially the same thickness. Direct contact of the tools used is usually visible in the result, a condition not always apparent in other techniques, where all evidence of the working method is eliminated.

Etymology

The word repoussé is French
French language
French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...

 and means "pushed up", ultimately from Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 pulsare, which means "to push". Repoussage is actually the correct noun
Noun
In linguistics, a noun is a member of a large, open lexical category whose members can occur as the main word in the subject of a clause, the object of a verb, or the object of a preposition .Lexical categories are defined in terms of how their members combine with other kinds of...

 to refer to the technique, with repoussé being an adjective referring to a piece to which the technique has been applied (e.g. "repoussé work", "repoussé piece"); however, in English it has become common to use repoussé as a noun, and this usage is reflected in this article.

Famous works

A famous example from antiquity is the late Eighteenth Dynasty mummy mask of Tutankhamun
Tutankhamun
Tutankhamun , Egyptian , ; approx. 1341 BC – 1323 BC) was an Egyptian pharaoh of the 18th dynasty , during the period of Egyptian history known as the New Kingdom...

. The lapis lazuli and other stones were inlaid in chased areas after the height of the form was completed. The majority of the mask was formed using the technique of repoussé from what appears to be a single sheet of gold (the ceremonial beard, Nekhbet
Nekhbet
In Egyptian mythology, Nekhbet was an early predynastic local goddess who was the patron of the city of Nekheb, her name meaning of Nekheb...

 vulture, and Uraeus
Uraeus
The Uraeus is the stylized, upright form of an Egyptian spitting cobra , used as a symbol of sovereignty, royalty, deity, and divine authority in ancient Egypt.The Uraeus is a symbol for the goddess Wadjet, who was one of the earliest Egyptian deities and who...

 were attached separately). The Warren Cup
Warren Cup
The Warren Cup is an ancient Roman silver drinking cup decorated in relief with two images of homosexual acts. The cup is named after its first modern owner, the collector and writer Edward Perry Warren, and was acquired by the British Museum in 1999...

 is a famous Roman silver cup, and the Mildenhall Treasure
Mildenhall Treasure
The West Row Treasure is a major hoard of highly decorated Roman silver tableware from the fourth-century AD, found at West Row, near Mildenhall in the English county of Suffolk...

, the Hoxne Hoard
Hoxne Hoard
The Hoxne Hoard is the largest hoard of late Roman silver and gold discovered in Britain, and the largest collection of gold and silver coins of the fourth and fifth century found anywhere within the Roman Empire...

, the Water Newton Treasure
Water Newton Treasure
The Water Newton Treasure is a hoard of fourth-century Roman silver, discovered near the Roman town of Durobrivae at Water Newton in the English county of Cambridgeshire. The hoard consisted of 27 silver items and one small gold plaque...

 and the Berthouville Treasure
Berthouville Treasure
The Berthouville treasure is a hoard of Roman silver uncovered by ploughing in March 1830 at the hamlet of Villeret in the commune of Berthouville in the Eure département of Normandy, northern France...

 are examples of hoard
Hoard
In archaeology, a hoard is a collection of valuable objects or artifacts, sometimes purposely buried in the ground. This would usually be with the intention of later recovery by the hoarder; hoarders sometimes died before retrieving the hoard, and these surviving hoards may be uncovered by...

s of Roman silver found in England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

 and northern France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

 with many pieces using these techniques. The prehistoric Gundestrup cauldron
Gundestrup cauldron
The Gundestrup cauldron is a richly-decorated silver vessel, thought to date to the 1st century BC, placing it into the late La Tène period. It was found in 1891 in a peat bog near the hamlet of Gundestrup, in the Aars parish in Himmerland, Denmark...

 has relief
Relief
Relief is a sculptural technique. The term relief is from the Latin verb levo, to raise. To create a sculpture in relief is thus to give the impression that the sculpted material has been raised above the background plane...

 panels on separate thin sheets on both the inside and outside.

A famous and unusually large sculpture
Sculpture
Sculpture is three-dimensional artwork created by shaping or combining hard materials—typically stone such as marble—or metal, glass, or wood. Softer materials can also be used, such as clay, textiles, plastics, polymers and softer metals...

 created with this technique is the Statue of Liberty
Statue of Liberty
The Statue of Liberty is a colossal neoclassical sculpture on Liberty Island in New York Harbor, designed by Frédéric Bartholdi and dedicated on October 28, 1886...

 in Upper New York Bay
Upper New York Bay
Upper New York Bay, or Upper Bay, is the traditional heart of the Port of New York and New Jersey, and often called New York Harbor. It is enclosed by the New York City boroughs of Manhattan, Brooklyn, and Staten Island and the Hudson County, New Jersey municipalities of Jersey City and Bayonne.It...

. The statue was formed by copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...

 repoussé in sections using wooden structures to shape each piece during the hammering process. A second example of monumental copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...

 repoussé sculpture is Portlandia
Portlandia
Portlandia is a sculpture by Raymond Kaskey located above the entrance of Michael Graves' Portland Building in downtown Portland, Oregon, at 1120 SW 5th Avenue...

 by Raymond Kaskey
Raymond Kaskey
Raymond Kaskey is an American sculptor.He was born in Pittsburgh. He studied architecture at Carnegie Mellon University and Yale University...

, which was installed in 1985 in downtown Portland, Oregon
Portland, Oregon
Portland is a city located in the Pacific Northwest, near the confluence of the Willamette and Columbia rivers in the U.S. state of Oregon. As of the 2010 Census, it had a population of 583,776, making it the 29th most populous city in the United States...

.

History

The techniques of repoussé date from Antiquity and have been used widely with gold
Gold
Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...

 and silver
Silver
Silver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...

 for fine detailed work and with copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...

, tin
Tin
Tin is a chemical element with the symbol Sn and atomic number 50. It is a main group metal in group 14 of the periodic table. Tin shows chemical similarity to both neighboring group 14 elements, germanium and lead and has two possible oxidation states, +2 and the slightly more stable +4...

, and bronze
Bronze
Bronze is a metal alloy consisting primarily of copper, usually with tin as the main additive. It is hard and brittle, and it was particularly significant in antiquity, so much so that the Bronze Age was named after the metal...

 for larger sculptures. Among the most famous classical pieces using this technique are the bronze
Bronze
Bronze is a metal alloy consisting primarily of copper, usually with tin as the main additive. It is hard and brittle, and it was particularly significant in antiquity, so much so that the Bronze Age was named after the metal...

 Greek
Greece
Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....

 armour plates from the 3rd century BC.

During the 3rd millennium BC
3rd millennium BC
The 3rd millennium BC spans the Early to Middle Bronze Age.It represents a period of time in which imperialism, or the desire to conquer, grew to prominence, in the city states of the Middle East, but also throughout Eurasia, with Indo-European expansion to Anatolia, Europe and Central Asia. The...

, in the Middle East, a variety of semi-mass production methods were introduced to avoid repetitive free-hand work. With the simplest technique, sheet gold could be pressed into designs carved in intaglio in stone, bone, metal or even materials such as jet
Jet (lignite)
Jet is a geological material and is considered to be a minor gemstone. Jet is not considered a true mineral, but rather a mineraloid as it has an organic origin, being derived from decaying wood under extreme pressure....

. The gold could be worked into the designs with wood tools or, more commonly, by hammering a wax or lead "force" over it.

The alternative to pressing gold sheet into a die is to work it over a design in cameo relief. Here the detail would be greater on the back of the final design, so some final chasing from the front was often carried out to sharpen the detail. The use of patterned punches dates back to the first half of the 2nd millennium BC
2nd millennium BC
The 2nd millennium BC marks the transition from the Middle to the Late Bronze Age.Its first half is dominated by the Middle Kingdom of Egypt and Babylonia. The alphabet develops. Indo-Iranian migration onto the Iranian plateau and onto the Indian subcontinent propagates the use of the chariot...

, if not far earlier. The simplest patterned punches were produced by loops or scrolls of wire. By Hellenistic times, combined punches and dies were in use.
In 1400 BC, the Egyptian Amarna
Amarna
Amarna is an extensive Egyptian archaeological site that represents the remains of the capital city newly–established and built by the Pharaoh Akhenaten of the late Eighteenth Dynasty , and abandoned shortly afterwards...

 period, resin and mud for repoussé backing was in use. In 400 BC, the Greeks were using Beeswax for filler in repoussé.

Repoussé and chasing are commonly used in India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

 to create objects such as water vessels. These vessels are generally made using sheets of copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...

 or silver
Silver
Silver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...

.

During the Hopewell and Mississippian
Mississippian culture
The Mississippian culture was a mound-building Native American culture that flourished in what is now the Midwestern, Eastern, and Southeastern United States from approximately 800 CE to 1500 CE, varying regionally....

 periods of the American Southeast
Southeastern United States
The Southeastern United States, colloquially referred to as the Southeast, is the eastern portion of the Southern United States. It is one of the most populous regions in the United States of America....

 and Midwest
Midwestern United States
The Midwestern United States is one of the four U.S. geographic regions defined by the United States Census Bureau, providing an official definition of the American Midwest....

 goods of repoussé copper were fashioned as ritual regalia and eventually used in prestige burials. Examples have been found with many S.E.C.C. designs such as Bi-lobed arrow motif headdresses and falcon dancer plaques. Although examples have been found in a widely scattered area (Spiro
Spiro Mounds
Spiro Mounds is an important pre-Columbian Caddoan Mississippian culture archaeological site located in present-day eastern Oklahoma in the United States. The site is located seven miles north of Spiro, and is the only prehistoric Native American archaeological site in Oklahoma open to the public...

, Oklahoma
Oklahoma
Oklahoma is a state located in the South Central region of the United States of America. With an estimated 3,751,351 residents as of the 2010 census and a land area of 68,667 square miles , Oklahoma is the 28th most populous and 20th-largest state...

, Etowah
Etowah Indian Mounds
Etowah Indian Mounds is a archaeological site in Bartow County, Georgia south of Cartersville, in the United States. Built and occupied in three phases, from 1000–1550 CE, the prehistoric site is located on the north shore of the Etowah River. Etowah Indian Mounds Historic Site is a designated...

, Georgia
Georgia (U.S. state)
Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788...

, and Moundville
Moundville Archaeological Site
Moundville Archaeological Site, also known as the Moundville Archaeological Park, is a Mississippian site on the Black Warrior River in Hale County, near the town of Tuscaloosa, Alabama...

, Alabama
Alabama
Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...

), most are in what is known as the Braden Style, thought to have originated at the Cahokia
Cahokia
Cahokia Mounds State Historic Site is the area of an ancient indigenous city located in the American Bottom floodplain, between East Saint Louis and Collinsville in south-western Illinois, across the Mississippi River from St. Louis, Missouri. The site included 120 human-built earthwork mounds...

 Site in Collinsville, Illinois
Collinsville, Illinois
Collinsville is a city located mainly in Madison County, and partially in St. Clair County, both in Illinois. As of the 2010 census, the city had a population of 26,016. Collinsville is approximately 12 miles from St. Louis, Missouri and is considered part of that city's Metro-East area...

.

Methods

It can take some time to create jewelery or art using repoussé and chasing techniques, although with practice, complex and delicate pieces can be made which would be virtually impossible to complete using any other method.

There are different metals you can use for chasing and repousse work, such as drawn steel, silicon bronze, copper, gold, silver and pewter. The higher the content of copper, the more malleable the material will be.

The process of chasing / repousse takes a lot of time due to the repetition of a number of time-consuming stages: The first step is the preparation of the metal by annealing
Annealing (metallurgy)
Annealing, in metallurgy and materials science, is a heat treatment wherein a material is altered, causing changes in its properties such as strength and hardness. It is a process that produces conditions by heating to above the recrystallization temperature, maintaining a suitable temperature, and...

; cleaning to remove the pitch
Pitch (resin)
Pitch is the name for any of a number of viscoelastic, solid polymers. Pitch can be made from petroleum products or plants. Petroleum-derived pitch is also called bitumen. Pitch produced from plants is also known as resin. Products made from plant resin are also known as rosin.Pitch was...

 between annealing and work; setting up; and careful work with punches. This process is typically repeated many times during the creation of a chasing/repousse work.

One method of repoussé and chasing is to place a thin sheet of metal on a bowl of chasers pitch. This chasers pitch can be pine rosin based that can be kept slightly soft with a heat gun or plumbers torch for relief work and hardens when cooled for chasing/planishing work. It can become extremely soft or liquefied when heated too much, becoming somewhat of a burn hazard. It is not recommended, nor necessary to heat the pitch to this degree.

The purpose of using pitch is to provide a solid base to work on, whilst allowing the metal to be pushed out and shaped without obstruction. The pitch is best worked on in a pitch bowl or "pitch board." The pitch bowl is a cast iron
Cast iron
Cast iron is derived from pig iron, and while it usually refers to gray iron, it also identifies a large group of ferrous alloys which solidify with a eutectic. The color of a fractured surface can be used to identify an alloy. White cast iron is named after its white surface when fractured, due...

 bowl which sits on a bag stuffed with sand
Sand
Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...

 or on a rubber ring specifically made for this purpose. This allows for greater stability, rotation
Rotation
A rotation is a circular movement of an object around a center of rotation. A three-dimensional object rotates always around an imaginary line called a rotation axis. If the axis is within the body, and passes through its center of mass the body is said to rotate upon itself, or spin. A rotation...

 and angling. The pitch is heated using a hairdryer, or an industrial blowdryer. If the pitch is too hard, the metal will be thinned. If it is too soft, you have very little control over the form. A good medium grade chasers pitch works well because it softens enough to allow for satisfactory relief and cools to a firmness that is sufficient for chasing, planishing and detail work.
Steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

 tool
Tool
A tool is a device that can be used to produce an item or achieve a task, but that is not consumed in the process. Informally the word is also used to describe a procedure or process with a specific purpose. Tools that are used in particular fields or activities may have different designations such...

s are used to work the metal. A "liner" is a steel tool/punch with a very thin, slightly rounded end, that is used to create the initial lines on the metal. The liner is hit on the end with a chasing hammer, pushing a thin line of metal into the pitch. The side facing up will consequently be the front of the piece. Once all the lines have been chased, the metal is then turned over on the pitch, and repoussé technique is then applied, using other various steel punches/tools to push the metal so that it is raised on the front of the finished piece.

Once the repousse is done - the design raised, the piece is inverted, and the voids are filled with warm pitch to help maintain its shape. The pitch should be allowed to set in the voids and cool before the piece is turned over and placed back on the pitch. Once the piece of metal is turned over and then chased, in that the details are refined and brought out. The design is worked many times, with numerous tools, before the final result is achieved.

Every time the metal is removed from the pitch bowl, it needs to be cleaned and re-annealed. Turpentine
Turpentine
Turpentine is a fluid obtained by the distillation of resin obtained from trees, mainly pine trees. It is composed of terpenes, mainly the monoterpenes alpha-pinene and beta-pinene...

 is used to remove the pitch, and a blow torch can also be used to burn it off.

When working with the pitch, make sure you are working with gloves, safety glasses and good ventilation and as always, when working with any type of open flame, make sure there is an appropriate fire extinquisher close by.

Tools

There are hundreds of tools which can be used. They are generally made by the jeweller/crafts person. They are typically made from bars of tool steel
Tool steel
Tool steel refers to a variety of carbon and alloy steels that are particularly well-suited to be made into tools. Their suitability comes from their distinctive hardness, resistance to abrasion, their ability to hold a cutting edge, and/or their resistance to deformation at elevated temperatures...

, which is forge
Forge
A forge is a hearth used for forging. The term "forge" can also refer to the workplace of a smith or a blacksmith, although the term smithy is then more commonly used.The basic smithy contains a forge, also known as a hearth, for heating metals...

d and tempered
Tempering
Tempering is a heat treatment technique for metals, alloys and glass. In steels, tempering is done to "toughen" the metal by transforming brittle martensite or bainite into a combination of ferrite and cementite or sometimes Tempered martensite...

 at the tip. These hardened steel punches may be purchased by a supplier, but the specialized punches are made by the jeweler or special ordered to suit a particular design. A saw
Saw
A saw is a tool that uses a hard blade or wire with an abrasive edge to cut through softer materials. The cutting edge of a saw is either a serrated blade or an abrasive...

 can be used to cut designs into the tip for making patterns, or the tool can be hammered onto a patterned surface, which will indent the tip. The end of the tool which is to be hammered should be bevelled to allow for expansion of the metal from repeated hammering. Some of the main styles of tool include: Liners, planishers, matting, and doming. Liners have thin tips, which are slightly rounded. If they are too thin they will cut the metal. They are used in the initial marking out of the design, and in the finishing stages to refine any thin outlines. Planishers have smooth, flat tips which are used for pushing out large, flat areas of metal. Matting tools have patterns cut into them, and provide detail to areas of the design. Matting tools can also be made by filing a thin line around a steel bar, hardening it, then snapping it. This will result in a fine grain pattern. Doming tools push out rounded areas of metal, and can either be round or oval, quite pointed or almost flat. An oxyacetylene torch, coal forge or propane forge is required for heating the steel sufficiently for forging. The more tools available, the easier it is to create a detailed, accurate piece.

Recipes for pitch

The traditional working surface is chaser's pitch which is usually a composition combining three substances: pure pitch, a filler (or stiffener), and an emollient (softening medium). There are a number of different recipes for making chaser's pitch. One example is:
  • 16 parts pitch
    Pitch (resin)
    Pitch is the name for any of a number of viscoelastic, solid polymers. Pitch can be made from petroleum products or plants. Petroleum-derived pitch is also called bitumen. Pitch produced from plants is also known as resin. Products made from plant resin are also known as rosin.Pitch was...

  • 20 parts plaster of Paris
  • 4 parts resin
    Resin
    Resin in the most specific use of the term is a hydrocarbon secretion of many plants, particularly coniferous trees. Resins are valued for their chemical properties and associated uses, such as the production of varnishes, adhesives, and food glazing agents; as an important source of raw materials...

  • 1 part tallow
    Tallow
    Tallow is a rendered form of beef or mutton fat, processed from suet. It is solid at room temperature. Unlike suet, tallow can be stored for extended periods without the need for refrigeration to prevent decomposition, provided it is kept in an airtight container to prevent oxidation.In industry,...



The pitch is heated until molten. Plaster of Paris is added a small amount at a time. Resin and tallow are then mixed in.

Pitch is backing and filler material preferably rosin based, but also petroleum based, used by metalsmiths to hold the metal in place while working it.

There is a flexible pitch used by chaser's referred to as Swedish pitch.

There are other pitch choices, with two very popular choices being Red (or sometimes referred to as brown) German Pitch and a versatile medium (grade/hardness) dark green chasers pitch. There is also a black pitch.

The different pitches are used preferentially and according to the type of chasing and repousse work being done.

This pitch material can be re-used indefinitely if used and stored properly.

See also

  • Metal spinning
    Metal spinning
    Metal spinning, also known as spin forming or spinning, is a metalworking process by which a disc or tube of metal is rotated at high speed and formed into an axially symmetric part. Spinning can be performed by hand or by a CNC lathe....

  • Embossing (manufacturing) - rolling sheet metal through dies to produce a raised or sunk relief design.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK