Anvils

Finding an anvil cheap or free

The anvil is said to be the only tool a blacksmith cannot make himself. With that said, there are two main options to go. First, is find a real anvil. They can be bought at full price, or often you can get them for free. Second is to use a replacement block of steel, which are sometimes just as suited and efficient. More on these options later. Let's delve into what makes an anvil a good anvil.

Science time again. I wrote the following article a while back, and again not all of this is completely necessary, but will give you a good understanding as to how it all works. Skip to the end for a summary. 

When looking for an anvil, we’re told a good trick to test if an anvil is good quality or not is the bounce test; let a hammer drop onto the face of the anvil using only it’s weight to push down and your hands just to stead the hammer. If it bounces only once or twice, it’s bad quality. If it bounces six or more times before coming to rest, it’s very good. But why is that? What makes an anvil good or bad and how does the above test reveal it?

Simply stated, a “bad” anvil will form the workpiece very little per given force in a hammer blow, whereas a “good” anvil affects the workpiece much more for the same force. So this is how it all works.

When you drop a hammer onto the anvil face, kinetic energy (whenever I use the term energy in this post, it will refer to kinetic energy) is transferred from the hammer to the anvil, and from the anvil deflected right back into the hammer. So why doesn’t the hammer bounce back up with the same speed it went down with? Why does it eventually stop bouncing? (remember nothing stops moving unless something, well, stops it from moving)

Let me explain elastic and inelastic collisions real quick. An example of an elastic collision are two hard steel balls, of equal mass and speed, hitting each other in a zero-gravity environment. Ball A is going five MPH to the right. Ball B is going five MPH to the left. They hit dead on. What happens? They bounce apart. Why? Ball A has transferred it’s kinetic energy to ball B, and vice versa, so after the collision ball A is going five MPH left, and ball B is going five MPH right.

An inelastic collision is where you have two balls of playdough in the same situation as above, striking each other dead on. What happens? They stick and flatten. What happened? Because the molecules were not rigid in relation to each other (the playdough is softer) the kinetic energy is used to expand the playdough outwards. Kinetic energy has to go somewhere, and as it cannot go as it had in the direction it was going, it is used to expand the playdough outwards, not into the other ball. The steel balls would do the same, but the force is not great enough to move the molecules in relation to each other, so it is transferred to the other ball.

So, going back to dropping the hammer on the anvil. If the anvil face is soft, (inelastic) the energy from the hammer is transferred into the hammer face, and then outwards and downwards, pushing the molecules away, into a dent. If the anvil face is hard (elastic) the energy cannot be used to move the steel molecules apart from each other (bonds are too strong), so it goes right back up into the hammer, pushing it back. Because no material we have is perfectly elastic (which would mean the molecules do not move in relation to each other at all, no material we know of has this property) some is used to move the molecules in relation to each other, and the rest goes right back into the hammer. Each time the hammer bounces a little more is lost until there is no more energy to keep it moving. If both the hammer and the anvil are hard, the hammer will fly back up with the same speed it had going down, which is why as a blacksmith you must be careful not to miss the workpiece.

So finally we can get to how this all relates to forging. For ideal forging, we want as much energy as we can to go into the workpiece, into moving the molecules in relation to each other. If the workpiece is hard, most of the energy is transferred from hammer, to workpiece, to anvil, and back to hammer with minimal amounts going into the workpiece. The ideal workpiece is inelastic. How do we make it harder? By heating it up so the molecules move easier in relation to each other. With a good hammer and anvil, the energy is transferred from the hammer into the workpiece. About half of the energy goes into moving the workpiece molecules, flattening it, and from there it spreads out from molecule to molecules until the effect is invisible. The other half of the energy is transferred through the workpiece to the anvil. Maybe half, but more like a third of that energy goes into moving the anvil molecules (but because the workpiece has spread the energy over such a large surface on the anvil, the effect is barely noticeable), then the rest goes right back up into the workpiece. Half of /that/ energy deforms the workpiece some more, while the remainder goes back into the hammer, pushing it upwards with just enough force not to shoot into the smith’s face, but enough to raise it so the smith doesn’t need to do any work to lift the hammer. Then the process repeats.

To summarize: a good anvil that will give the most efficient forging is one that is hard and so sends kinetic energy back into the hot steel, and one that is massive (has mass) enough not to send all the kinetic energy dispersing into the ground. 

To test the hardness of an anvil, use a hammer (which is generally very hard as it is small and easy to heat treat). Drop the head on the face of the anvil, barely holding the hammer so as to let it bounce freely. Higher pitch is a sign of hard steel, but the main sign is the number of bounces. More bouncing is means a harder anvil. A softer anvil will bounce less or not at all, with lower pitch, as if you were bouncing the hammer off a piece of wood. 
 

 

This is about the amount of bounce you want for a good anvil. Less bounce gives you more inefficient forging

This is about the amount of bounce you want for a good anvil. Less bounce gives you more inefficient forging

This is about the amount of bounce you want for a good anvil. Less bounce gives you more inefficient forging

Generally most smiths recommend an anvil weighing about 75 pounds. If you're scrounging for steel chunks that could work, make sure it passes the "Bounce Test", but it doesn't necessarily have to weigh 75 pounds (though more weight means more efficient forging), much less will do, as long as the mass is as much directly below the work zone (area of the face you will be forging on) as possible. For example, most people recommend or use a short segment of rail road track for an anvil. The slightly rounded top is perfect for a forging surface, but there isn't very much mass underneath that. Instead, mound the track vertically, end up, so almost all the mass of the track is directly below the work zone. This constricts how much area you have to forge but will give more efficient forging. 

So, to find an anvil you need something that has three things. 

  1. Weight. The more the better, though you can go pretty light and still be able to forge. I've used a sledgehammer head with good results. The more weight directly under the work zone the better. 
  2. Hardness. Use the bounce test to determine if it's hard enough. Around four or below is too soft (number of bounces will vary according to force, but it will be easy to tell). A good anvil will have around five bounces and a bunch more really small ones. 
  3. Clean, flat face. You really only need about a 3x3 inch area. Use an angle grinder to flatten the face if it's pitted, and round off the edges; otherwise if you unknowingly have the workpiece at an angle you'll hit a deep mark in the steel.

Where to find makeshift Anvils

A short section of railroad track is a very common source of makeshift anvil. Hard enough to not be worn away by hundreds of trains going over it, common enough to easily find. Setup by Laramie Jackson

A short section of railroad track is a very common source of makeshift anvil. Hard enough to not be worn away by hundreds of trains going over it, common enough to easily find. Setup by Laramie Jackson

  • Short section of Railroad Track. There will often be pieces cast away near a railroad track; excess cut off by railway workers. Often you can find out when construction will be done at nearby tracks and ask a worker to cut you off a small piece. Junkyards, thrift shops, and antique stores often have them too. 
  • Sledgehammer head. Not the most efficient but very easy to get and it works quite well. This is what I used until I got a real anvil. Secure face up with a strap through the eye. 
  • Granite block. I have never personally used it, nor seen one used. However I have heard from several sources that it works pretty well. 

In general, there are many uses in construction vehicles for large steel pieces. Sometimes in junkyards you'll even find plain steel blocks, which work perfectly. As a bladesmith, not farrier or blacksmith, you really don't need the horn or hardy hole. If you're looking for a makeshift anvil, the junkyard is the place to go. 

One thing I will say however, do not use the anvil on the back of a vise for forging knives. This is what I used in the very first, and after two or three forgings, the steel cracked and split all the way through. It is horrible steel, possibly cast iron. Do not use it for forging. 


Real Anvils

"Amboß eines Hufschmiedes" by I, Claus Ableiter. Licensed under CC BY-SA 3.0 via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:Ambo%C3%9F_eines_Hufschmiedes.JPG#/media/File:Ambo%C3%9F_eines_Hufschmiedes.JPG

"Amboß eines Hufschmiedes" by I, Claus Ableiter. Licensed under CC BY-SA 3.0 via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:Ambo%C3%9F_eines_Hufschmiedes.JPG#/media/File:Ambo%C3%9F_eines_Hufschmiedes.JPG

Eventually you will want to upgrade to a real anvil. It's not impossible to find one for free, but pretty unlikely. A good anvil is the crown of the blacksmith. Anvils tend to run $3-$4 per pound, and you will want one at least 75 pounds. Some people buy from harbor freight, but I've heard many bad reports from that. If you think you've found a good one, use the bounce test, and look up the brand name. In anvils, as a general rule, older is often better. They're easy to clean up, and there are a lot of modern ASO's (anvil shaped objects) made from cast iron for garden decorations that you want to stay away from. 

Antique shops often have them, but they can be expensive. The most common place is on someone's property; handed down to them from their grandfather and just left in the garden to rust. It was not long ago that the US had a blacksmith for every town and those anvils had to go somewhere. It takes a bit of digging but it is possible to track these anvils down, and especially if you already know the owner is quite possible to get for free. I personally bought mine from an old tools dealer who was passing through; met him at a place only fifteen minutes drive from where I live. Since then, just poking around, I've found about 25 anvils fit for forging within a half hours drive radius from where I live. This article has given me the most help and was very useful. 

Mounting the Anvil

So you've found an anvil and now need to mount it. First thing you need to know is how high it should be. To determine the height, stand up straight against a wall, arms by your side, hand in a fist. Mark with a pencil where the end of your fist is on the wall. This is how
height the anvil should be.

 


If the anvil is any higher, then the hammer is at an upward angle, hitting with the "chin" of the hammer. This makes a deep indent. Same problem if the anvil is too low, though this time it will hit with the "forehead".  Use a wood stump for the base: it helps deaden the noise and isn't brittle. Stack and nail boards underneath to adjust the height. 

Securing the Anvil

Keeping the anvil still while forging is essential. Sometimes it is heavy enough to keep itself still but that's not often the case. There are four ways to lock the anvil in place.

  • Iron Staples
  • Straps
  • Chains
  • Carved Depression

If the anvil has holes at the bottom you can bolt it with, by all means do so, but that's not common. 

Iron Staples

Use metal staples, straps, or chains if the anvil has "feet" (corners), such as a real anvil or a railroad track. You don't need to secure all four corners, just two opposite ones will do. If you want the anvil to be permanently fixed to the stump, use metal staples (pretty much iron hooks over the feet). This is the most secure way to mount the anvil. You will need to do some forging however. Get some rebar of appropriate length, forge or grind both ends into points, then forge it into a U-shape, big enough to fit snugly over the anvil foot. Place it as far up the foot (close to the anvil) as possible, and hammer it down into the wood. The grip in the rebar will hold onto the wood. That anvil will be going nowhere. 

Straps

Straps are tighter, more secure, and easier to do than chains. Simply cut a piece of cloth strap long enough to loop over the foot and a quarter way down either side of the stump. Get two long screws and screw them all the way into either end of the strap. Screw one end a quarter way down the stump, below the anvil foot. Loop the other end over the foot and pull it taught against the stump on the other side. Put the screw at an angle to the stump; the point of the screw inserting at a point further down than the strap can reach by an inch or so. Screw it in slowly. As it goes in, it'll pull the strap very tight. 

Chains

Chains are more sound-deadening than straps or staples, but not very tight. Get a long chain and screw one end into the stump with a screw and washer. Loop the chain as tight as you can around the "waist" of the anvil, with the other end of the chain hooked around the corner opposite where you secured the first chain. Pull down tight and secure with screw and washer. 

Carved Depression

 



This is for post anvils, that have no corners to put a strap, chain or staple over. This is a hole that the anvil inserts into, deep enough to keep it from falling over and tight enough to keep from bouncing around.
This can be done directly into the stump with a router, or if you don't have one, a hand drill and chisel (I did it for a sledgehammer head anvil). Takes a while but worth it. More secure is to build a container around it, preferably welding one from steel, but you can also just nail one together with wood. Get creative. 

Silencing Your Anvil

Forging is loud. If your neighbors are nearby you could disturb them and get complaints. You can't completely silence your anvil unfortunately, but you can get it pretty quiet. The key to silence is vibration, which as you know, is what sound is. Harder things such as solid pieces of steel tend to vibrate more, softer things like wood vibrate less. Think along the lines of absorbing vibration. Areas of the anvil like the horn and heel (opposite end of the anvil from the horn) tend to vibrate the most, and many people have said placing a powerful magnet on those areas will do the trick. Making sure the anvil is tight against the stump also helps, as the vibration is channeled into the wood and there deadened. Many chains wrapped around the waist, as well as making a metal barrel, filling it with sand, then putting a steel plate over the top (all this instead of a wood stump) will work wonders. My house is quite far from neighbors so all I've done is used a chain.

There are many, many ways to quiet an anvil, more than I could list hear. A quick google search will give you a myriad of different ways of doing it. Remember, the key is absorbing vibration; the more it vibrates, the more noise you get.


So there you have it; the guide on getting an anvil. Next up will likely be Hammers and Tongs, though because that article will be fairly short, I may release that one sooner. Remember, any comments or questions I will be happy to answer!