Monday, May 26, 2014

Why Anvils Are Shaped As They Are And Why Blacksmiths Often Tap The Anvil After A Few Strikes On The Object They’re Working On

Original source : http://www.todayifoundout.com
Posted : February 2012
Author : Daven Hiskey

Anvil shape has evolved greatly since the earliest anvil-like objects.  These primitive objects used for anvils were typically made of stone, often just a slab of rock. The first metal anvils were made of bronze, then wrought iron, and, finally, steel, which is the material of choice today for anvils, though cast iron is also used in low-end anvils (cast iron is quite brittle for this particular use and absorbs more of the hammer blow’s energy than steel does, so it is not preferred).

Over the centuries, the common shape of the anvil has evolved from a simple slab to the shape most of us associate with an anvil today, namely the “London Pattern”, which became common in the 1800s.  While the length and overall size of the various elements can vary from anvil to anvil, the key features of the “standard” design are typically a horn, a step, a face, a hardy hole, and a pritchel hole.  The primary use of these various elements is as follows:

·    The horn is the “front” end of the anvil which is curved.  This allows the smith to hammer different curves into the piece they are working on, with the precise curve depending on how and what part of the horn they hold the piece on while they hammer it.   Some anvils also come with multiple horns, of differing shapes and sizes.

·    The step is the flat area next to the horn, just below the face.  This is often used as the cutting area, using the edge of the step to “cut” a piece while hammering it. However, frequent use of the step for this purpose can also damage it, so the use of tools attached to the anvil for cutting is often preferred for non-hobbyists.

·    The face is the main large flat slab where most of the hammering takes place.  It also contains the hardy hole and the pritchel hole.  Unlike the step, it often features slightly rounded edges so that the edges don’t cut into the metal being pounded on the face.

·    The hardy hole is a square hole through the anvil that allows you to secure various tools in the anvil.  These tools can include chisels, various swages (used for shaping or marking the metal, generally a block of metal with a recess for forcing the metal into the shape of the recess), bickerns (smaller, specialized versions of the horn), etc.  The hardy hole can also be used directly for an aid in bending or in hole punching.

·    The pritchel hole is a round hole meant as an aid in punching holes through the metal you’re working on, but obviously the hardy hole can be used for this as well as mentioned. The pritchel hole can also be used for holding tools.  So, basically, the pritchel hole is a round version of the hardy hole.

On a related note, if you’ve ever watched a smith work, you’ve probably noticed many of them will strike whatever they’re working on a few times, then follow it up by lightly tapping the anvil’s step or face a couple times.  You may have heard that they do this to cool the hammer down by having it come in contact with the anvil, but this is the opposite of what they’d want to do.  Warm hammers and warm anvils are actually what they want, because it keeps the hot metal they’re working with from cooling down as quickly, so it requires less heating while shaping, which saves time.  Further, the very brief contact between the hammer and the anvil isn’t going to transfer very much heat, even if the anvil is quite cold.

In reality, they are not actually tapping the anvil for any real purpose other than to simply either rest their arm while they quickly examine the results of the last few strikes or to simply keep their rhythm while they examine the piece. In the former case, resting the hammer on the anvil next to the piece is simply a convenient place to rest it.  With it in this position, it is a shorter distance to bring the hammer back up to the appropriate striking position, over say, letting one’s hammer and arm rest at one’s side while the piece is examined. In the latter case, some just find it nice to continue their hammering rhythm while they examine what they’re working on, rather than stopping completely.  They only tap the anvil, rather than strike it, both to save energy and because you should never pound an anvil directly with the hammer as it can cause slight deformations to form which would then be transferred to whatever you’re working on in the future.

Bonus Facts:

·    Humans aren’t the only animals on Earth that use objects as anvils.  For instance, Chimpanzees often use sticks or rocks as hammers and logs or rocks as anvils in order to crack open nuts.

·    Anvil firing (the practice of launching an anvil in the air with gunpowder) was once traditional in various places in the world, particularly in the Southern United States.  Typically, one anvil is placed upside down with its concave base then filled with gunpowder.  Another anvil is then placed on top of that anvil right-side up, so their bases match and with a fuse coming out of the inner concave area filled with gun powder.  Depending on the quality of gunpowder, the amount used, and the weight of the anvil, when the gunpowder ignites, the anvil will be shot into the air to various heights.  This somewhat dangerous practice was often used in substitute for fireworks at certain celebratory events.  It was also once traditionally used on St. Clement’s Day (Pope Clement I is the patron saint of blacksmiths and metalworkers).

·    While blacksmith is a familiar term, you may not have heard of a farrier, mentioned above.  A farrier is basically a hoof care specialist that, among other things, is typically skilled at making horse shoes.  At one time, most blacksmith’s were also skilled farriers and vice-verse.  However, today this is usually not the case with modern farriers leaning more towards just being horse hoof care specialists and modern blacksmiths, while able to make horseshoes, usually are not skilled at also caring for horse hooves.

·    The name “farrier” comes from the Middle French word “ferrier”, meaning “blacksmith”.  This Middle French word in turn derives from the Latin “ferrum”, meaning “iron”.

·    The name “Blacksmith” simply references the fact that they are smiths (deriving from the word “smite”, meaning “to hit”) that work on “black” metal, with the metals typically turning black from a layer of oxides after being heated.  Obviously the oxide layer is generally later ground off.

·    Anvils were once commonly made of wrought iron, rather than steel.  Wrought iron is just iron with a very low carbon content (lower than steel or cast iron).  It was once considered pure iron, but by today’s purification standards this is no longer the case.

·    Steel is simply iron that has a small amount of carbon added, usually .2%-2.1% (other materials such as manganese, chromium, tungsten, etc. can also be used). The net effect of adding carbon or the like is that the iron is significantly hardened.

·    When enough carbon is added (around 2.1%-4%) to the iron, rather than steel, you get cast iron, which is derived from pig iron.  Cast iron is much harder than steel, but the price for this is that it is much more brittle and less ductile.  The name “cast iron” comes from the fact that it has a relatively low melting point and is easy to cast.

·    Pig iron is simply the result of taking iron ore and smelting it with some sort of carbon fuel, such as charcoal or coke.  The name comes from the fact that the branching structure of the molds for pig iron ingots coming off a main line has the appearance of piglets suckling on a sow (an “ingot” just means a shape suitable later processing or transportation, such as a traditional gold bar type shape).

·    While not up to modern standards, the earliest known steel making was done over 4000 years ago in present day Turkey.  Steel pieces have also been found in East Africa from over 3400 years ago.  The Chinese are known to have begun quenching their steel as recently as about 2000 years ago.

·    Iron is the most common element by mass overall of any on Earth, though it is only the fourth most common element in the crust of the Earth.

·    Iron is formed from decayed nickel-56. This nickel is produced in stars and is subsequently spread about via stars large enough to go supernova doing so, with it being the last element produced in those stars before they go supernova.

~Blog Admin~

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