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Want to do sheet metal work, but don’t know where to start? Don’t know the difference between copper and brass? And what are all those tools for? Let’s get you into some of the basics then. There are many kinds of metal – mercury for instance, is a metal, but since it is liquid at room temperature, we really don’t need to talk about it in this context! The most common metals you will see in sheet form, are various types of steel, aluminum, copper, brass, tin and bronze. If you want to get into jewellery making, silver and gold are also available as sheets or leafs – though usually somewhat smaller than the less precious metals. More information ContractorsIn Roofing & Waterproofing
Steel sheets are commonly used in many types of manufacturing, from car bodies to machine parts and enclosures. Copper sheet is used for roofing and for many decorative uses. Brass looks a little like gold, when polished and laquered. It is often used for plaques and signs of the fancy sort. Aluminum is light and well known for the stiffness it provides in extruded profiles, but in sheet form it is used for roofing, aircraft bodies, cars, etc. Here is a quick run-down of how these metals perform in typical metalworking tasks:
Steel welds well, aluminum is a bit more difficult, but it can be done with a bit of experience and the right equipment. Brass, bronze, copper and tin is not normally welded, it is soldered.
All these metals can of course be cut – it is a question of the method used. Steel can be sheared or cut with an angle grinder. The other metals mentioned are best sheared or perhaps band-sawn. They are softer, which means they will easily clog up a grinding disc, as well as tend to cause dangerous backlash when using an angle grinder.
Of all these, steel and aluminum have the highest melting points – not really doable outside of a proper industrial setup. Bronze, copper, brass and tin are much better suited for small scale and hobby casting.
Steel is the most prone to rust – although not so much so as cast iron. Other common metals also oxidize, but often more slowly. Copper develops a nice green patina when it oxidizes, which is often purposely used to effect, sometimes even by accelerating the process chemically. Bronze art objects exist from some of the earliest civilizations, which speaks volumes about how slowly it corrodes. Iron objects only a few decades old can sometimes be found to have almost rusted away, even when they were originally coated with a protective finish.
The traditional sheet metal working techniques are repose and chasing, which basically means hammering the metal into shape. The softer metals are great for this, whereas steel is generally too hard and brittle, and needs to be heated to a red hot state to be worked in this manner. Not always practical for the hobbyist.