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Moving into the Milwaukee plant of Grady Foundries, Inc., another magnet load of scrap, just about

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the only material used here in the production of steel for castings.

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Ordinary steel is made of varying percentages of raw iron mixed with scrap, but stainless,

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nitroloy, and other high quality steels are made entirely of scrap, alloyed of course with

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all amounts of certain other elements. One of those elements is carbon, and the amount of carbon

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in the melt has important effects on the character of the steel being produced. Here's how skilled

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steelmen determine whether the carbon content is right. They make a test bar in a little mold and

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harden it with a quick chilling. Out of the mold, the test bar gets another dip, then is placed in a

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special jig to be broken in two so the newly exposed surfaces can be read, as revealing to a

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veteran melter as the pages of a book. But checks like that are only approximate when compared to

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the painstaking chemical analyses constantly being made at Grady, analyses that allow the

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breakup of the metal to be rigidly controlled. Steel is mixed with those other elements we mentioned

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according to many different recipes, you might call them, depending on what conditions the finished

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product will have to face. It's vitally important that specifications be fought to the letter,

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hence the endless taking of samples. Each one is identified as to the heat.