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116- Trade Skills 116- Trade Skills

Basics of Sheet MetalBasics of Sheet Metal

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Sheet Metal HistorySheet Metal History

• Sheet metal dates back to ancient days where many workers toiled for many hours to hammer a single sheet of metal into its final form.

• The Bronze age marked the beginning of widespread use of metals in everyday life.– Ancient people discovered copper and bronze

could be made into tools, shields, swords, and many decorative items.

• Sheet metal dates back to ancient days where many workers toiled for many hours to hammer a single sheet of metal into its final form.

• The Bronze age marked the beginning of widespread use of metals in everyday life.– Ancient people discovered copper and bronze

could be made into tools, shields, swords, and many decorative items.

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Sheet metal historySheet metal history

• This discovery created rapid growth in populations and in trade among different nations.

• Towns and cities developed, as people moved to metal producing areas as people where needed to mine and process the raw material, and create the tools and weapons. – The use of the metals meant that stronger weapons could

be made and used to defeat less advantaged civilizations in war.

– The bronze age lasted for several thousand years and spread throughout the middle east, Asia, and Europe.

• This discovery created rapid growth in populations and in trade among different nations.

• Towns and cities developed, as people moved to metal producing areas as people where needed to mine and process the raw material, and create the tools and weapons. – The use of the metals meant that stronger weapons could

be made and used to defeat less advantaged civilizations in war.

– The bronze age lasted for several thousand years and spread throughout the middle east, Asia, and Europe.

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Sheet metal HistorySheet metal History

• It was followed by the Iron age• The iron age brought the discovery of iron and

brought even more growth to civilizations.– Iron was now the metal being used to make tools, weapons,

machinery, and other items.

• The industrial revolution changed the way products

were made and how work was done.– Machines such as rolling mills transformed the production of

sheet metal. – Sheets could now be made by running metal through rollers,

creating flat sheets or rolls. It had to no longer be processed into sheets by hand.

• It was followed by the Iron age• The iron age brought the discovery of iron and

brought even more growth to civilizations.– Iron was now the metal being used to make tools, weapons,

machinery, and other items.

• The industrial revolution changed the way products

were made and how work was done.– Machines such as rolling mills transformed the production of

sheet metal. – Sheets could now be made by running metal through rollers,

creating flat sheets or rolls. It had to no longer be processed into sheets by hand.

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Sheet Metal HistorySheet Metal History

• The use of computers continue to revolutionize sheet metal work. Computes now do jobs that were previously done using calculators, hand tools, or hands. – Example: computer software is used to design

the complex curves and bends found on aircraft bodies and wings, and automotive bodies.

• Computer software is used to design the ducts and the fittings to install them.

• Most sheet metal cutting and punching are done by computer numerical controls (CNC) lasers or punch presses.

• The use of computers continue to revolutionize sheet metal work. Computes now do jobs that were previously done using calculators, hand tools, or hands. – Example: computer software is used to design

the complex curves and bends found on aircraft bodies and wings, and automotive bodies.

• Computer software is used to design the ducts and the fittings to install them.

• Most sheet metal cutting and punching are done by computer numerical controls (CNC) lasers or punch presses.

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Sheet Metal HistorySheet Metal History

• Sheet metal work has evolved into a well established, skilled craft.

• Sheet metal workers use many processes to fabricate, install, and maintain a variety of products. – These products include HVAC systems,

automotive and aircraft bodies, buildings, and appliances.

• Sheet metal work has evolved into a well established, skilled craft.

• Sheet metal workers use many processes to fabricate, install, and maintain a variety of products. – These products include HVAC systems,

automotive and aircraft bodies, buildings, and appliances.

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So, what is sheet metalSo, what is sheet metal

• Sheet metal is any type of metal produced in flat sheets or rolls.

• Sheets and rolls each have advantages and disadvantages. – These are important to

consider when selecting material for a project.

• Sheet metal thickness varies, but generally is less than ¼” thick– Metal thicker than ¼” thick is

called plate.– Extremely thin metal used for

decoration is called foil.

• Sheet metal is any type of metal produced in flat sheets or rolls.

• Sheets and rolls each have advantages and disadvantages. – These are important to

consider when selecting material for a project.

• Sheet metal thickness varies, but generally is less than ¼” thick– Metal thicker than ¼” thick is

called plate.– Extremely thin metal used for

decoration is called foil.

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Sheet metal sizeSheet metal size

• Sheet metal can be ordered directly from the mill in any size, dimension, or gage.

• There are no limits on available sheet metal sizes.– However, commonly used sized included 96” or

120” lengths. – Smaller sheet metal shops make 30”X 96” and

36” X 120” sizes.

• The thickness of sheet metal is its gage. – Each gage represents a specific metal thickness.

• The lower the gage number, the thicker the metal. • Example: 18 gage sheet metal is thicker than 26 gage.

• Sheet metal can be ordered directly from the mill in any size, dimension, or gage.

• There are no limits on available sheet metal sizes.– However, commonly used sized included 96” or

120” lengths. – Smaller sheet metal shops make 30”X 96” and

36” X 120” sizes.

• The thickness of sheet metal is its gage. – Each gage represents a specific metal thickness.

• The lower the gage number, the thicker the metal. • Example: 18 gage sheet metal is thicker than 26 gage.

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• Gage is also the name of the tool used to measure gage.

• The American Standard Wire Gage, is the standard measurement used for nonferrous metals ( metals other than iron)

• The recognized commercial standard in the Unites States for plate iron, steel, and uncoated steel is the United States Standard Gage for Sheet and Plate Iron and Steel.

• Gage is also the name of the tool used to measure gage.

• The American Standard Wire Gage, is the standard measurement used for nonferrous metals ( metals other than iron)

• The recognized commercial standard in the Unites States for plate iron, steel, and uncoated steel is the United States Standard Gage for Sheet and Plate Iron and Steel.

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• It is more commonly referred to as the U.S. Standard Gage. It is based on weight in ounces per square foot.

• To use a gage, insert the sheet metal edge in the slot of the gage. – Find the smallest slot the

metal easily slides into. The slot will have a number above it. That is the gage.

• It is more commonly referred to as the U.S. Standard Gage. It is based on weight in ounces per square foot.

• To use a gage, insert the sheet metal edge in the slot of the gage. – Find the smallest slot the

metal easily slides into. The slot will have a number above it. That is the gage.

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Types of metals Types of metals

• There are many types of metal:– Steel– Aluminum– Brass– Copper

• Sheet steel is commonly used in school shops.

• Sheet steel can be coated or solid ( uncoated).– The coating reduces rust and corrosion on the

steel.

• There are many types of metal:– Steel– Aluminum– Brass– Copper

• Sheet steel is commonly used in school shops.

• Sheet steel can be coated or solid ( uncoated).– The coating reduces rust and corrosion on the

steel.

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• The most commonly used coated sheet steel are galvanized steel and tin plate.

• The most commonly used solid sheet steel is stainless steel. – Stainless steel is an alloy, which is a combination

of two or more metals.

• The most commonly used coated sheet steel are galvanized steel and tin plate.

• The most commonly used solid sheet steel is stainless steel. – Stainless steel is an alloy, which is a combination

of two or more metals.

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Metal characteristics and applicationsMetal characteristics and applications• Uncoated sheet steel has a bluish black

surface. Uncoated steel easily corrodes easily, after assembly, the product is coated.– Sheet steel applications include stovepipes, safety

guards, and parts for electrical appliances.

• Galvanized steel is used often in the sheet metal shop.

• Galvanizing is the process of coating sheet steel with hot, liquid zinc. – Galvanized steel has a shaded appearance. The

zinc coating protects the metal from corrosion.

• Uncoated sheet steel has a bluish black surface. Uncoated steel easily corrodes easily, after assembly, the product is coated.– Sheet steel applications include stovepipes, safety

guards, and parts for electrical appliances.

• Galvanized steel is used often in the sheet metal shop.

• Galvanizing is the process of coating sheet steel with hot, liquid zinc. – Galvanized steel has a shaded appearance. The

zinc coating protects the metal from corrosion.

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• The most common uses for galvanized steel are in HVAC ducts, gutters and downspouts.

• Cold- rolled steel is not processed into its final shape and thickness until it is cooled.– It has a silver gray color to it and has a smooth

finish. School lockers and cabinets are made with this type of metal.

• Copper sheet is easily recognized by its reddish brown color. – It is an excellent conductor of electricity and

contains a small quantity of alloy. • Commonly used to make pots, pans, roofing and

printed circuit boards

• The most common uses for galvanized steel are in HVAC ducts, gutters and downspouts.

• Cold- rolled steel is not processed into its final shape and thickness until it is cooled.– It has a silver gray color to it and has a smooth

finish. School lockers and cabinets are made with this type of metal.

• Copper sheet is easily recognized by its reddish brown color. – It is an excellent conductor of electricity and

contains a small quantity of alloy. • Commonly used to make pots, pans, roofing and

printed circuit boards

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• Tin Plate is sheet metal coated with a layer of pure tin, making it corrosion resistant. – Tin coating is food safe, meaning it can safely

come in contact with surfaces that touch food. – It is used in kitchen utensils, tin cans, dairy

equipment.

• Aluminum is used in alloys with other metals, such as magnesium or manganese, allowing for easy forming and bending. – Typical uses include automobile trim, ductwork,

and electronic parts.

• Tin Plate is sheet metal coated with a layer of pure tin, making it corrosion resistant. – Tin coating is food safe, meaning it can safely

come in contact with surfaces that touch food. – It is used in kitchen utensils, tin cans, dairy

equipment.

• Aluminum is used in alloys with other metals, such as magnesium or manganese, allowing for easy forming and bending. – Typical uses include automobile trim, ductwork,

and electronic parts.

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• Stainless steel is steel that contains 12-25% chromium. It is durable metal that resists rust and corrosion. – Stainless steel is used in restaurants and

cafeteria equipment, dairy equipment, escalators, and household appliances.

• Brass is an alloy made of copper and zinc. The zinc content is not more than 40% of the total. May contain some lead, tin, aluminum also, but in small amounts. – Used in belt buckles to decorative plaques.

• Stainless steel is steel that contains 12-25% chromium. It is durable metal that resists rust and corrosion. – Stainless steel is used in restaurants and

cafeteria equipment, dairy equipment, escalators, and household appliances.

• Brass is an alloy made of copper and zinc. The zinc content is not more than 40% of the total. May contain some lead, tin, aluminum also, but in small amounts. – Used in belt buckles to decorative plaques.