Common Metal Shapes and Terminology

Authored by Tractor Supply Company

When working with metal, it is helpful to know what type of metal you are working with, such as steel, aluminum, or alloys so you can use the right type of metal and shape of metal for your particular metalworking project. Whether you are working with metals in a pure state, as alloys or as protective coverings for other metalworking jobs, knowing what type of metal is best for each type of job is important to getting your DIY project done correctly.

Metal stock, especially steel and aluminum, is available in many standard shapes, ready to be cut, threaded, bent, or joined. The following shows the most common stock shapes, and methods of measurement. Some dealers will also take orders for shapes custom-extruded to virtually any specification.

Channels, I-beams, and H-beams have two parallel arms, called flanges, connected by a perpendicular piece called the web. As a layman, you may find the conventions of metal measurement confusing in some instances. But the metal industry adheres to the following terminology: The length of a flange from end to end is called flange width, and the length of the web is called the depth of the shape.

Common metal shapes and measurement method

Angle

Leg length by leg length by leg thickness

Strip or band

Thickness by width (pieces 1/4" and thicker are flats, pieces wider than 12" are sheets)

Channel

Depth (web length) by web thickness by flange width

Flat

Thickness by width (pieces 3/16" thick and less are strips or bands, pieces wider than 8" are plates)

Hexagon, Octagon

Width (from side to side, not corner to corner)

Round tube or pipe

Outside diameter by wall thickness

Square tube, rectangular tube

Outside width (by outside height for rectangular tube) by wall thickness

I Beam, H Beam

Depth (web length) by web thickness by flange width

Plate

Thickness by width (pieces 3/16" thick and less are sheets, pieces 8" wide and less are flats)

Round or rod

Diameter

Sheet

Thickness by width (pieces 1/4" and thicker are plates, pieces 12" wide and less are strips or bands)

Square

Width

How to identify metals by appearance and use

Whether you are working with metals in a pure state, as alloys or as protective coverings for other metalworking jobs, knowing what type of metal is best for each type of job is important to getting your project done correctly.

The metals you are likely to encounter as a do-it-yourself (DIY) metalworker are listed below. You'll find surface, interior, properties and usage descriptions with each metal. These will help identify various metals.

Cast iron

Surface: Dull gray

Interior: Silvery white or gray

Properties: Hard, brittle, rusts slowly

Uses: Engine blocks, machine bases, fireplace equipment, bathtubs

 

Steel; low carbon (mild)

Surface: Dark gray or rusty; may have black scales

Interior: Bright silvery gray

Properties: Soft, bendable; easy to work; rusts quickly

Uses: Wrought-iron work; furniture, fencing, architectural trim

 

Steel; medium carbon

Surface: Dark gray or rusty; may have black scales

Interior: Bright silvery gray

Properties: Hard and strong; rusts quickly

Uses: Nuts, bolts, axles, pins

 

Steel; high carbon (tool-grade)

Surface: Dark gray or rusty; may have black scales

Interior: Bright silvery gray

Properties: Hard, brittle; rusts quickly

Uses: Cutting tools, hand tools

 

Stainless steel

Surface: Clean silvery gray

Interior: Bright grayish silver

Properties: Tough; difficult to work; does not rust or corrode

Uses: Kitchenware, furniture, picture frames

 

Aluminum

Surface: Gray to white, dull

Interior: Silvery white

Properties: Light, soft, malleable; very easy to work or cast

Uses: Siding, roofing, gutters, flashing, auto and marine parts

 

Copper

Surface: Reddish brown to green

Interior: Bright copper

Properties: Soft; easy to work; good electricity conductor

Uses: Wiring and plumbing; major component of brass and bronze

 

Brass and bronze

(copper combined with zinc or tin, along with other metals)

Surface: Yellow, green or brown

Interior: Reddish yellow

Properties: Soft; can be worked hot or cold; casts and polishes well

Uses: Marine fittings, architectural trim, bearings

 

Nickel

Surface: Dark silvery gray, some green

Interior: Bright silvery white

Properties: Strong, hard; corrosion-resistant

Uses: Plating, alloys

 

Nickel-copper (Monel)

Surface: Dark gray

Interior: Light gray

Properties: Stronger and harder than nickel; corrosion-resistant

Uses: Corrosion-resistant construction

 

Lead

Surface: Bluish gray

Interior: White

Properties: Very heavy and soft; poisonous; corrosion-resistant

Uses: Protective linings, solder (with tin), alloys

 

Tin

Surface: Gray

Interior: Silvery white

Properties: Soft, malleable; corrosion-resistant

Uses: Galvanizing, alloys

 

Pewter (tin, antimony and copper)

Surface: Gray

Interior: White 

Properties: Soft-casts well; modern pewter contains no lead, making it nonpoisonous

Uses: Eating utensils, decorative items

Zinc

Surface: Blueish gray

Interior: Blueish white

Properties: Soft but brittle; corrosion-resistant

Uses: Galvanizing, alloys

 

Silver

Surface: Dull gray

Interior: Bright silver

Properties: Soft; easy to work and cast

Uses: Eating utensils, decorative items, plating, solder

Gold

Surface: Yellow

Interior: Bright gold

Properties: Soft but tough; corrosion-resistant; easy to work and cast

Uses: Jewelry, electronics work, plating

 

More metal work knowledge

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