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Decorative Metalwork
Karen Ussher, Tammy Desharnais
February 2003, Vancouver, BC, Canada
A successful designer must have a good working knowledge of the development of design and its stylistic counterparts. That being said, it is important that the designer is knowledgeable about all materials used for a given project. When looking at decorative metals, it is important to know how the materials originated, and what specifications go into using that material correctly for today’s building environments. Therefore, to be a competent qualified designer, you should research the materials used, protecting yourself and the client from future distress & liability.
It is necessary to look back to our earliest built environments to understand how the design of metalwork has evolved over the centuries, influencing our ideas today. In the following report, we will relay all pertinent information on the topic of “Decorative Metal”. Firstly, we will take a look at the history of metalwork. Secondly, we will examine the various types of metal that are available. Thirdly, we will focus specifically on the two main metals used today, iron and stainless steel.
General History
At the end of the new Stone Age, humans developed the ability to extract metals from the rocks, to blend metal and to form metals. The earliest metal artifacts discovered are copper pieces c.7000 BC. They had been hammered into shape and heated in a fire to make them malleable rather than brittle. Stone tools and weapons were being replaced by more efficient metal ones.
By c.800, there was a wave of skilled metalwork. Wooden furniture was now decoratively embellished with metal straps, hinges, bolts and building of various sorts. Bronze doors for cathedral fronts began to replace carved wooden ones. Generally doors were sculpted in low brief showing biblical scenes. Inside the churches metals were used for various designs.
During the Renaissance, c.1450, artists did not hesitate to design decorative panels, lanterns, candelabra, door hardware, knockers and other articles of architectural and household use.
Early American, c.1600, fireplace accessories were made of iron, as were coking pots and caldrons, locks, hinges, candlesticks and lamps. Also, brass was being used for drawer pulls, cabinet knobs and hinges. The brass of this time had relatively more zinc and less copper than today’s brass, it was paler and more yellow and though to resemble gold. In addition, silver jewelry and household wares were in great abundance and demand.
By the early 1700’s, wrought iron was being used extensively. The most impressive displays were grilles and gratings, which were used for protection. Also, black iron candelabras and accent pieces were used to decorate homes.
In the 1860’s metal was used for ceiling surfaces. Sheets of corrugated iron were used in utilitarian spaces in warehouse, factories, schools and hospitals. Metal was both fire-resistant and less expensive than wood or plaster. In 1895, lighter and more easily installed tiles of stamped tin were in wide spread residential use. They were available in hundreds of patterns, some imitating stucco or brick and some manufactures could also make custom designs. Tin surfacing materials, particularly the ceiling tile remained popular, until World War I brought a metal shortage. Today ceiling tiles are available, but of 28 gauge steel with a tin finish.
Stainless steel was invented in the middle of the 19th century. Stainless steel has found uses as interior surfacing, beginning with column covers for the Empire State Building in 1932.
Canadian History
One of the first minerals resources mined in Canada was iron ore, along with copper and coal. Before permanent European settlements were established in Canada, there is evidence of Inuit exploitation of iron meteorites for metal. Also, at the 13th century, Viking settlement at L’Anse Aux Meadows, Newfoundland, local bog iron was roasted and wrought to make nails for the ships. About 1670, deposits of bog iron were found in the swampy areas near Trois-Rivieres, Quebec.
By the 1740’s, Canada’s first ironworks, Les Forges du Saint-Maurice at Trois-Rivieres, was turning out top quality cast iron stoves, pots, Kettles, bullets and cannons to serve the needs of the pioneer settlers. The most spectacular and revolutionary use of iron, and then steel, was in the construction of bridges and buildings. In the latter half of the 19th century, new methods of manufacturing made steel cheap and plentiful.
Metals
Metals are very versatile as they can be shaped by melting and casting, rolling, extruding, machining, welding, drilling and bending. Metals are used for structural and decorative purposes either alone or in combination with other materials. Hundreds of different types of alloys of metals are available. The strength of metals contributes to their utility in slender, durable shapes not possible with other materials, such as wood, masonry or ceramics.
There are two classifications of metals: ferrous (iron bearing) and non-ferrous (non-iron) types. More than 60 different metal alloys and hundreds of combination exist.
Ferrous Metal
Iron
Pure iron is a soft material, too weak to shape. Adding carbon as an alloy increases its strength, as well as its resistance to warping and cracking. Iron is the main element used in making steel, but it can be manufactured alone a wrought or cast iron.
Wrought iron was developed about the 14th century with the introduction of blast furnaces. These furnaces produced unrefined iron called pig iron. The pig iron was refined by re-melting to become wrought iron in a high-purity, malleable material.
Cast iron was melted in furnaces and poured into casts of various shapes. It is hard, brittle and fairy resistant to corrosion. It was developed about 1700 and became a substitute for wrought iron, since it could be mass-produced as casting rather than having to be hammered and bent.
Steel
Steel was invented in the mid-1800s. It is an alloy containing iron, manganese and proportions of carbon. It is stronger, more ductile and less brittle than iron. Steel can be cast, bent, welded, rolled and drawn into many shapes for the use as a building material. It is used for fasteners, structural framing, concrete reinforcing and a host of other functional and decorative applications. With the addition of other alloys, steel can be made corrosion resistant; it is also exhibits varying strengths or ductility. It can be coated to develop a protective oxide rust to prevent further deterioration.
Stainless Steel
Stainless Steel was developed in the early 1900’s. It has chromium added to make it corrosion resistant. It is used where greater protection is needed from moisture, such as in flashings, railings, hardware, fasteners, sinks, countertops, furniture and cooking utensils. Stainless Steel surface finishes are tough and can be polished to a mirror quality or brushed to a low luster. Stainless Steel panels are available for use on walls or as column covers, corner guards and splashguards.
Non-ferrous Metals
Most of the non-ferrous metals are alloys and resist corrosion, used in interiors.
Aluminum is available in a variety of fabricated forms and is used for structural framing, doorframes, screens, hardware, flashing, railings and furniture. It is lightweight, is easily worked, does not deteriorate, and is a good reflector of heat. Aluminum is produced by casting, rolling and extruding. Aluminum is rolled using steel rollers. Extruding aluminum forces molten through a die shaped to the desired configuration, producing a long, continuous and accurate section.
Brass: alloy of copper and zinc; takes high polish, but tarnishes readily; re-polish or add protective coating; easily shaped by casting, rolling and stamping; yellow color; it uses in lighting fixtures, hardware, bolts, screws, furniture and accessories.
Bronze: originally copper alloyed with tin, but now alloyed with various elements of tin, silicone and aluminum; fairly hard and durable, patinas with ages; brownish red color; it uses in sculpture, bells, hardware and plaques.
Chromium: used mostly as alloying element; can be brushed or polished; durable; doesn’t readily tarnish; used in plating blue-white; it uses in lighting fixtures, furniture and small appliance.
Copper: resistant to corrosion; surface will tarnish unless polished or protected with coating; ductile; malleable; good conductor of electricity and heat; reddish orange color that oxidizes to dull greenish blue/brown; it uses in electrical wire, water piping, roof flashing, gutters, cookware and accessories.
Gold: considered a precious metal; take high polish; easily worked; made in thin sheets for gold leafing; it uses in accessories, inlays and decorative elements.
Lead: resistant to corrosion; alloyed with tin to make pewter; soft; very dense; easily worked; vapors can be a health hazard; bluish-white color; it uses in waterproofing, radiation shields and stained glasswork.
Magnesium: resembles aluminum; alloyed with other metals; easily worked; resists corrosion; it uses in furniture and hardware.
Nickel: used primarily as an alloy with other materials; takes a bright polish; makes other metals harder, corrosion resistant, ductile; grayish-white color; it uses in cooking utensils, sinks and hardware.
Pewter: alloy of tin and other metals; takes high polish or rough finish; resists tarnish; can be cast, hammered, machined; warm gray color; it uses in lighting fixtures, tableware and accessories.
Silver: alloyed with other metals to increase hardness; alloyed with copper for sterling silver; takes high polish; ductile; malleable; tarnishes easily; white metallic color; it uses in accessories and jewelry.
Tin: soft metal often alloyed with others; non-rusting and tarnish resistant; easily worked; produced mostly in sheet form; soft silvery metal; it uses in light fixtures, accessories and as tin foil.
Titanium: important alloy; titanium oxides used in materials to make them white and bright; easily worked; used as alloy for structural material; it uses in furniture.
Zinc: used mostly as alloy with other materials; easily worked; bluish-white color; it uses in major galvanizing or plating for corrosion resistant finishes.
General Description And Composition
Iron
Iron is a malleable and ductile metallic transition element. It has nine isotopes and is the fourth most abundant element in the earth’s crust. Quite reactive, oxidized in moist air, displaces hydrogen from dilute acids and combines with non-metallic elements. Iron, usually appears dark brown, from oxidation or impurity, but when pure, or on a fresh surface, is a gray or white metal. It is easily oxidized by moisture, and it is attacked by many corrosive agents.
Stainless Steel
Stainless Steel is a family of iron based alloys that must contain at least %10.5 Chromium. The presence of chromium creates an invisible film that resists oxidation and makes the material “passive” or corrosion resistant. If damaged, it repairs itself with the help of some water and naturally occurring oxygen in the air. This family can be simply and logically grouped into 5 branches (410 – 430 – 304 – 316 – 2205). Each of these branches has specific properties and a basic grade or type. In addition, further alloy modifications can be made to tailor the chemical composition to meet the needs of different corrosion conditions, temperature ranges, strength requirements, or the improved weld ability, machine ability, work hardening and formability.
Manufacturer / Cost
During the research of this project, we have found that all the metal work companies receive their raw materials from local distributors. These distributors carry all metals. When ordering stainless steel from local distributors, they mostly come in sheets of 4x8 or 4x10 sheets, but can be custom ordered. The different types include: hot rolled, cold rolled, pickled and oiled, and stain coat. These also come in many different finishes, for example, mirror finis, mill finish, brushed, checker plate, #4 and #2 finishes. There are also different techniques that you can have done to provide some texture, like having the steel brushed with a sanding drill to achieve many different affects.
When ordering iron from local distributors, it comes in flat bar, angle and tubing. Usually come in 20 foot pieces, but can also be custom cut. Delivery time is 2 days for fabric, longer for custom cut. The following are local distributors: Harvard Metal, A. J. Forsythe, Samuel Specialty Metal and Wilkinson Steel. When ordering a piece, for example a spiral staircase, exact measurements are required. After this is finished, the staircase must be made to fit the space, but there are special requirements for a spiral staircase. There cannot be more than a 7- ľ” riser and cannot be less than a 22 degree angle, having these stipulations makes every job a custom piece. This piece would take a week to complete and install. Also, depending on the amount of decorative work and detail, these can get very ornate, increasing the price. For an average spiral staircase that is 5’ in diameter, the cost to build, for a very plain one, would be around $3000 up to %5000 for a very ornate and detailed piece. All of the companies that we interviewed to manufacture at their place of business, but will assemble onsite. The installation process usually takes about 8 hours for a staircase, which is welded into place, and is done usually by the company, not outside contractors.
Metal has so many different aspects and a variety of uses. Objects commonly made of metal include: range hoods, security bars, railings and decorative artwork.
The companies we interviewed specialized in creating custom pieces. Therefore the cost and installation varied from piece to piece. Stainless steel ensures functionality in its most beautiful form. Stainless steel is compatible with wood, natural stone or textiles, when used in design. It produces interesting focal points as well as creative accents.
Finishes and Colors
Iron left in its raw form would oxidize and rust. Therefore many different colors can be applied to prevent this from happening. Iron can be primed and painted in a variety of colors. Also be powder-coated, this process I baked on, the finish is black and matte. As well iron can have a variety of techniques applied to make finishes that look antique, polished, brushed or eve a blackened rustic finish.
Steel can have a variety of different finishes as well, for example: brushed, satin coat, sanded, mirror, aluminized, etched, blasted. As well as light electrochemical colors placed over brushed or satin finishes, or embossed, swirl patterns and lined patterns. Stainless steel has a very industrial look and so it is used in places to create an urban warehouse feel.
Uses
Iron
Iron can be used for many different purposes. It can be used for railings on stairs or around balcony’s, for furniture, bed frames and lamps. Iron can also be used for gates, window security bars and many different decorative art pieces. It can be used to cast wood burning fireplaces or barbecues, and make wine and pot racks. Iron can be used in combination with wood, on railing, with stone, or a variety of other metals. Iron is very versatile and quite beautiful.
Steel
Used in the preparation of food products, stainless steel has smooth surface that microorganisms are unable to anchor themselves to. Thus, hygienic reasons steel is commonly used in restaurants. It is stainless, which means that the invisible film of chromium rich oxide is non-porous and prevents the stainless steel surface from reacting with the atmosphere. If minor scratches occur, it has the ability to self-heal and return to its initial state almost instantaneously; this makes it one of the most durable materials available. Stainless steel has many different uses, including: kitchen sinks, gutters, doors, widows, food processing equipment, chemical vessels, ovens, heat exchangers, stairs, railings, a variety of car or engine parts, knife blades, surgical equipment and fasteners.
The following are some of the many benefits of using stainless steel:
It is corrosion resistant (lower alloy grades resist corrosion in atmospheric and pure water environments, while high alloyed grades resist corrosion in most acids, alkaline solutions, and chlorine bearing environments, properties which are utilized in process plants), fire and heat resistant, impact resistant, and the strength of steel is incomparable. In this modern age of steel making techniques, stainless can be cut, welded, machined, and fabricated. Stainless is often a less expensive material as it has a long lifecycle.
Maintenance
There is very maintenance associated with the care of iron and stainless steel. Once installed, objects rarely need maintenance. Cleaning and care require mild detergent and water on a soft cloth or sponge. Nothing abrasive should be rubbed on the surface, even steel wool will not scratch the stainless.
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