Brass Metals And Its History

The most popular surviving form of brassware is probably the domestic candlestick. These were made usually in pairs, and are rarely older than the middle of the seventeenth century. At that time they were on domed circular bases, with a pan to catch drips of wax halfway up the stout central column. Early in the eighteenth century, shaped bases and tall stems with grease-pans at the very top came into fashion. With variations from time to time, this style continued in use until the candle was no longer the principal illuminant in the home.

Metal works
Brass was made into dishes of various sizes, often with embossed designs of Biblical scenes with inscriptions on the borders. These are sometimes still to be seen in use as alms-dishes in churches.

Chandeliers of brass with curved branching arms were made in England and also on the Continent. Many of them date from the seventeenth century, but most have been made more recently in response to continual demand.

Ormolu
This is the French name (literally or moulu, molded gold) for articles and furniture mounts made of bronze and gilded. The piece having been made in bronze was carefully and finely finished by chiseling and polishing and then coated with a mixture of mercury and gold. This amalgam was subjected to heat and the mercury evaporated leaving the gold deposited on the surface. Finally, the gold was burnished where required, or left matt.

The French developed the art of designing and making furniture mounts from ormolu, and were equally proficient at making clock cases, candlesticks, inkstands and other suitable pieces from the same material. Much thought was given to the mounting of porcelain in ormolu, and vases and figures with bases and other enhancements were valued highly for decoration. They fetch high prices today, but only if the mounts are genuinely of the eighteenth century. From 1745 to 1749 a tax was levied on ormolu, and pieces were stamped in a similar manner to silver. The mark is a letter ‘c’ beneath a crown, but as it was in use apparently for no more than four years specimens bearing it is rare.

German ormolu is not dissimilar to French, although seldom as highly finished. In England, the firm of Boulton and Fothergill, of Soho, Birmingham, made good ormolu at the end of the eighteenth century.

Old ormolu is sometimes found with the gilding in good condition, but frequently it is worn away on the surfaces exposed to by wear and tear; its greatest enemy is metal-polish, which should never be used on it. As with Sheffield plate, ormolu can be replated electrically but the appearance of the old cannot be reproduced exactly.

Beside brass ormolu, the French for articles and furniture mounts made of bronze and gilded, developed the French name. They developed the art of designing and making furniture mounts from this ormolu and they were equally proficient at making clock cases, candlesticks, inkstands and other suitable pieces from this material. Then the German and the English followed later on in the eighteenth.

Sheet Metal In The Automotive Industry

Sheet metal has been used extensively to produce automotive body panels and been decreased with the advent of fiberglass ones, sheet metal is still the most popular material for manufacturing automobiles today. The addition of lasers and robotics to the automobile manufacturing process has further expanded the way that sheet metal is processed.

Lasers

Lasers have been used in production facilities since the 1960′s. Today, they are used to cut, form holes, engrave, weld or heat treat sheet metal for use in automotive production.

Lasers are used in applications that rely on precise measurements and exact alignments.

The adjustment of lasers is measured in micrometers, or millionths of a meter.

There are many different types of lasers used to alter sheet metal and plastics in the automotive industry.

Carbon dioxide laser- uses a mixture of carbon dioxide, nitrogen and helium to produce a continuous laser output

Continuous-wave laser- this type of laser produces light beams continuously rather than in controlled pulses

Excimer laser-emits light in a UV spectrum that is used for producing high quality edges on parts that are prone to cracking or thermal damage; it falls into the category of pulsed-gas lasers

Gas laser-any laser that uses a gas mixture as the lasing medium; common gases are argon and carbon dioxide

Pulsed laser-emits light in controlled pulses and is preferred for thin materials ; it can be used to create intricate details and work in tight corners without burning

Ruby laser-a solid state laser that uses a synthetic ruby crystal with a chromium impurity as the lasing medium

Solid-state laser-a type of laser that uses a crystal or glass as the host for an impurity to produce the lasing action; especially useful for precise measuring and spot welding

Yttrium aluminum garnet (YAG) laser-ranges in power from a few milliwatts to more than 400 watts; used for cutting, drilling, heat treating and welding operations

Robotics

Robotics are often used for repetitive tasks, monotonous jobs or those parts of the manufacturing process that are physically difficult or take place in environmentally unpleasant conditions. They are directed by computer programs and perform precise operations without human intervention.

Lasers and robotics have significantly increased the speed at which sheet metal can be processed in the automotive manufacturing process. Continued technological advancements in these two areas will further increase the cost effectiveness and productivity of automotive manufacturing facilities.