I'd rather have a real anvil, too, but have you priced one lately?
This one didn't cost me anything, if you take out some welding rods and a nut and bolt. An equivalent 50 lb. standard anvil you would buy from a quality blacksmith supply company (you probably have one or two of those in your neighborhood) is more than $300.
Ok, so the price is a factor. But what about usability - can you do the same things with it? Well.as they say, it's as good as a real anvil, if you haven't used a real anvil. But, truthfully, I have, and I can say that it is nearly as good. Almost.
A word of warning: this Instructable requires cutting steel with a torch, and arc or Acetylene welding; at that stage, and all others, wear appropriate protective equipment.
Step 1: First...
First, you find a piece of railroad track. That may be easier said than done, especially in more urban areas. While there may be plenty of track there, I'm almost positive they don't want you pulling it up.
In the country, especially in areas where there used to be railroad tracks, it is a little more doable. You might find pieces in scrapyards, auto repair shops, antiques shops, or various other places. When they pulled the track up in my area, scraps were available everywhere. I can even show you places where surveying markers were made out of sections of track driven into the ground!
You don't need a lot of track - two feet will be oodles. You can get by with eighteen inches, so that is in your favor.
You will also need about the same length of a truck leaf spring, so, while you are poking around, looking for a section of track, ask about a piece of spring, too. Remember, dents and rust pitting on the surface of the spring will be transferred to the work, so try to find a smooth piece.
Step 2: Flame On!
Having found a suitable piece of track, the next thing you need to do is cut it to an approximately anvil shape, which amounts to a horn on one end (the other end should already be square.) Don't try to do it with any other tool than a torch, unless you happened to be in the Château d'If with nothing but time. You might have to pay for this, but it can't be too much; it will only take ten minutes.
While you are torching, make four holes in the flat (bottom) side of the track, one near each corner to secure it to whatever you mount it on. This is usually a piece of tree trunk.
At this point, once you grind the edges of the track section smooth, you have something that looks like an anvil, and which will actually suffice to bang on.
Unfortunately, this is the one step I don't happen to have a photo of.
Step 3: A Little More Anvil-y
The next step is to make a flat surface on the top of the anvil. This is where the section of truck leaf spring comes in. Depending on how long your track section is, you will need perhaps a foot to eighteen inches of spring. You may as well torch it, since you are doing it anyway. One end (the end to be mounted at the base of the horn) needs to be square; the other can be ragged for the time being, just be a little generous with your measurements.
You will notice your spring section is curved. You will need to remove the temper from the steel to make it flat and stay that way. The simplest way to do it is to cook it on a gas grille until it gets red hot. (Charcoal is the next best way.) If you let it cool naturally, you are normalizing the steel; that isn't good enough. You need to anneal it - take it from the heat and bury it in a big pile of ashes, or - less desirable - sand. It will stay hot a long time. A long, long time. I burned myself once on a piece of cast iron that had been buried in ashes for four hours. Just forget it overnight.
The annealing process removes the stress from the molecules of steel, allowing it to be easily bent and not spring back.
Once your spring section is cool enough to handle, weld the square, forward end to the base of the horn - the point where the triangular horn becomes the same width as the rest of the track. Weld it solidly. Because of the curve, the rest of the spring will be higher than the top of the track.
Using a series of clamps, or some kind of press, flatten the spring section to the top of the track. Spot weld it in several places, then remove your clamps and weld the two pieces together. This will take quite a few rods - you are trying to fill the void between the two. If you use an arc welder, it will take a lot of heat, too. Acetylene is better, if you can do it.
Once you have completed the welding (it will be hot!), cut the end of the spring section off about 4" from the rear (away from the horn) end of the track.
At this point, the assembly will actually resemble an anvil. You're getting there!
Step 4: Drill Some Holes
If you look at the top of a real anvil, you will see two holes - a square one, called a hardy hole, and a round one, known as the pritchel hole.
The hardy hole holds hardy tools; tools that need to be inserted in a specific orientation and which are not intended to move. Typical hardy tools are a blade for cutting iron (not steel - hot wrought iron cuts like leather), a fork for bending metal, etc.
The pritchel hole is just a hole (about 5/16") for punching holes through metal.
Step 5: Add a Hardy
SInce you can't drill a square hole through steel, I made my hardy hole round. (5/8") I then tightened a bolt and nut through the overhang, bolt on top, and welded the nut in place on the underside.
I made a number of hardy tools, such as a cut-off, welding them to the head of different bolts and oriented across the anvil face. Loosen to change them and when you tighten the next one up, it is oriented properly.
They are nothing like as quick to use as a square hardy, which can be removed and replaced in a regular anvil in a second, but they do the job.
Step 6: Finishing Up
If you will recall, you removed the temper from the leaf spring section before welding it to the top of the track. Now you want it back.
Get a large, metal trashcan and fill it almost to the top with water. Near it, build a big pile of leaves, twigs, sticks, and larger pieces of wood, enough fo burn hotly for about thirty minutes. Light it and put your new anvil in it. Make the fire as hot as you can and let the anvil cook for half an hour.
Wearing gloves and using a crowbar, digging bar, etc., lift the anvil and drop it in the water. Then run.
Obviously, the results will be sudden and dramatic. The water will immediately begin to boil, and continue to boil. Keep a hose nearby, and keep adding water if it boils over. You want to cool the anvil quickly, to reintroduce the stresses inside of the steel, only this time, the anvil face will be hardened (not tempered) flat, instead of curved, as it originally was.
The end result will be a perfectly usable anvil, complete with hardened surface and horn. It will suffice for general shop use, and works fine for blacksmithing hardware that can be used around the house or farm, or which you can sell if you are so inclined.