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Hammer face and anvil size


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The rr track is turned on end and the bulb section of the track is used as an anvil.  The anvil is larger than the hammer face, so what is the problem?

 

If you use an anvil the size of the deck of an aircraft carrier, only the metal under the hammer face will move with each blow.

 

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This is the hammer face, a piece of 1/2 inch stock and the end of a piece of rr track being used as an anvil. 

 

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The reason the rr track is turned on end is so the mass of the track is directly below the hammer blow and provides the most resistance to the force of the hammer, there by moving the metal.

 

If you put the metal on a mile (5,280 feet) of rail road track, the mass directly below the hammer blow provides the resistance to the force of the hammer, not the other 5,279 feet of track.

 

The rr track anvil face is too small to hit? 

The impact target size does not change if you put it on an real anvil that has a face of 5 inches wide and 30 inches long. It is still 1/2 inch stock and the same hammer. You either hit the target with the hammer or you don't.

 

Test it out in your own forge with your own anvil. Put a piece of 1/2 inch round bar on the fire, get it hot and hit it one time hard with the hammer. Do you have a hammer face depression in the round bar or did you turn the entire length of round bar into flat stock with a single blow?  Only the metal under the  hammer face moves. 

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One of the arguments for not needing a monster anvil...Francis Whitaker was often heard to say, "Can you do better work on your 250 than I can on my 150?" - or words to that effect.

 

Of course, larger stock requires a larger hammer, which then would suggest using a bigger anvil (or power hammer).  Everything is proportional and relative to the situation at hand.

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I'm about to do an experiment on a 20" section of railroad track.  I'll be using it in the "post anvil" position, and my goal is to incorporate as many useful surfaces into the track as I can.  Ex. grind a hot cutting edge and cold cutting edge into the web, turning the base of the track into tapered fullers, etc.  The point of the experiment to prove that you can have a single, portable tool that is commonly scrounged for little to no money, but is still versatile enough to do almost anything a smith could want to do.  Working on a real anvil is great, but learning how to maximize the potential of something cheap and easy to find is a valuable thing, especially for folks that are just getting started.

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I do not think turning rr track on end or a 6" square cube of steel makes a difference it is how it is connected to the earth that is the real point. Sure the aircraft carrier is very cool but the impact of an hammer on steel would have little effect on its displacement un less you had a real big hammer. maybe you could use the launcher rams as a hammer that would give you forward motion.

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my bad, I had called a freind carl when we were doing live discussion and Im glad I did! Id confused joint fatigue with damage and made assumptions about vibration and mass. Carl told me that the reason for aching joints was that with no rebound from a smaller anvil having to LIFT the hammer constantly was what was causing the problem and that was why you wanted mass. basically the opposite of my statement above. Im still keeping my anvil though :P

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The point of the post was that only the area under the hammer face moves with the impact of the hammer face. 

 

On the top side

If you have 2 foot section of steel hot and a hammer face of 1-1/2 inches diameter, only 1-1/2 inches of the steel can move with each hammer blow.

 

On the bottom side

If you have a 2 inch diameter anvil or a 20 inch diameter anvil only the metal under the 1-1/2 inch diameter hammer face can move.

 

Test it out in your own forge with your own anvil. Put a piece of round bar on the fire, get it hot and hit it one time hard with the hammer. Do you have a hammer face depression in the round bar or did you turn the entire length of round bar into flat stock with a single blow? Only the metal under the hammer face moves. If you have different results, please take photos and show us how it worked for you.

 

The weight of the anvil, how it preforms, and how the anvil is connected to the stump and/or ground is a topic for another discussion. We need to work on one piece of the equation at a time, then all them together.

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So, what you are saying, Glen, is that the metal moved is determined by the smallest interface. A sharp chisel moves a smaller area more deeply than a fuller. A fuller moves a smaller area more deeply than a flattie.

 

We call this "the cowpie theory of blacksmithing." B)

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My general rule is: The metal will move where 1. Force is directed into the metal, and 2. Where the metal is in a condition (malleable/hot) in which the force directed onto the metal will cause it to move. 

 

This means the plane in which the metal is struck the above statement is true. The location on the metal where the strike occurred will deform and the portion not struck will not be deformed. However, on the opposite side (the anvil face) there is more surface area in contact with the anvil. When an object is struck the entire object tends to go in motion (Newton's Laws). That motion will be stopped by the anvil, causing the deformation to be at a maximum directly under the hammer blow, but also present nonetheless in close to the impact. 

 

Take for example a long piece of steel that has a radius placed on the deck of the aircraft carrier with the radius face down. The steel is then struck with a hammer. The result would not be present under the hammer but a general reduction of the radius due to the large surface contact with the aircraft carrier. This is generally the case if the entire piece of steel is under the same conditions (composition, temperature, etc.). But the area directly under the hammer face could be the only area impacted by the strike if that was the only portion of the steel that was heated. Generally this is not the case. 

 

All this being said it does not discredit the viability of the rail anvil. It does a very good job at directing force into the steel in a very controlled fashion. 

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