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Reviews Review by George Dixon in the Blacksmith's Bookshelf The "New Edge of the Anvil" is more that just a reissue of a work that has been a standard for beginning blacksmiths ever since it was first published over a decade ago. The first aspect of change that is apparent are the new drawings. They are excellent. Information is conveyed far more readily in illustrations when the are done well, and this book abounds in them. The point of this and every review here is how much technical information is contained in the book and how easy it is to understand. The "New Edge" is packed with the kind of information anybody starting their journey into blacksmithing wants to find. Tools, process and projects are all well represented. Beyond this is a section on metallurgy, so you can understand what is happening to the metal on heat treating and forging. There is a section on design basics, so you can begin to explore the rules of proportion and rhythm in a visual sense and a series of tables that cover weights and sizes of materials. The last part of the book has examples of artist-blacksmith's work. This section ranges from Samuel Yellin to contemporary artist. With the inspiration of the varied work in the portfolio section for energy and the chapters on tools and how to use them for direction, the "New Edge of the Anvil" comes as close to required reading as possible If ever there was a first book to start a Blacksmith's Bookshelf with then this is it. As an aside, if anyone wants to get a feel for what good drawing looks like, get this book. Review by Nol Putnam (nolp@shentel.net) from The is THE one book you need to get started as a blacksmith. The New Edge of the Anvil is a revised and expanded edition of Andrews' earlier and most successful book. I urge all my students to buy, read, use and then reread this book. Clear words, excellent pictures, good explanations, tables, charts...all you need to encourage you to pick up a hammer and start hammering. The new sections include wonderful pictures of historical ironwork (go practice making some of these!) and then the directions that six contemporary smiths are taking. I confess that I am one of these smiths, and that I have known the author for years. Because this is such a good resource, it is wonderful to be able to recommend it heartily without our friendship compromised. Buy it! Metallurgy for the Blacksmith TOP Metallurgy is the science and technology of metals. It concerns the extraction of metals from their ores, the refining of metals and the relationships between physical and mechanical properties of metals and their composition, mechanical working and heat treatment. Metallurgical information is helpful to any blacksmith, whether he is doing general blacksmithing or tool making. If you are a general blacksmith, then you need only understand the very basic principles; however, if you are a tool smith, then you will need a broader understanding. This does not mean that you will have to be a metallurgical engineer to make good tools, but that with some metallurgical knowledge, you will be able to select the correct material, forge it properly and heat treat it to develop the desired physical properties. The basic forging processes are made possible because the iron becomes plastic and can be forged when it is heated to a cherry red and above, up to a light yellow. Iron can be welded when it is heated to a light yellow. When heated to a dazzling white, iron begins to melt and "burns;" this destroys the metal for forging purposes. The structure of iron and all its alloys is crystalline. Plastic deformation of crystals is possible through the generation and motion of crystal defects called "dislocations." These deformation processes operate with less deformation force as the temperature of the iron is increased. Thus, when iron is heated, it becomes more plastic. Generally, the higher the heat, the easier it is to form the metal. A piece of iron is actually composed of many individual iron crystals, called grains, each having a different orientation of its crystal axes in relation to the neighboring grains. Normally, the grain size is too small to observe without the aid of a microscope. Sometimes, a fractured piece of iron will show evidence of the individual grains of iron that are visible to the unaided eye. The grain size is very important for determining the strength of iron: the more refined (smaller) the grain size, the stronger the iron and the tougher (resistance to fracture on impact) it is. There are two factors affecting the grain size that the smith can control at the forge: the temperature of the metal and the nature of the mechanical working (forging). When iron is heated and then forged, the forging refines, or makes the grain smaller. This hammer refining must continue until the iron cools below the critical temperature. If the forging stops before the iron is cherry red, or the iron is reheated without further forging, the grain growth will resume. Welding heat greatly increases the grain size. However, the weld can be hammer-refined to break up the coarse grain. With this type of control at the forge, the smith doing general metal work can resolve most problems. Mild steel can be used for simple tools only. As a tool designer you must use special steels for tools that will be tough, hard and durable. To create these steels, alloying elements are added to the iron. The major alloying element added to iron is carbon. The chart of maximum attainable hardness shows the effect of increasing amounts of carbon in steel. Steels with only 35 to 45 points of carbon can be used where moderate hardness is required. (Steels begin to respond to heat treatment with around 35 points of carbon.)
Hardness is the ability of a metal to withstand being deformed by indentation. This can be measured by a machine called the "Rockwell hardness tester." There are other tests, however, only the Rockwell C hardness scale will be referred to here. A relative degree of hardness can also be determined by a file. (See "File Test" in Resources.) Chart 3 shows another relationship of carbon to iron: the differences of tempering temperatures on the hardness of three different steels for equal tempering times. Notice that there is a greater difference of hardness between the steel with 35 points of carbon and the one with 80 points than there is between the steel with 80 points and the one with 120 points.
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