Blacksmithing

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Safety

  • Wear safety glasses, long pants, and closed-toed shoes. Avoid synthetic fabrics. Cotton is good. Wear ear plugs if you like (the power hammer in particular is very loud). Aprons and gloves are available if you want them. Beware of the boiling frog situation in which you grow acclimated to holding warm metal and suddenly discover you're holding hot metal that will burn you.
  • Orange metal can burn you severely.
  • Black/gray metal can burn you worse. Never touch black/gray metal unless you know for certain it isn't hot.
  • If you dip a piece of hot metal into the tank and it dries, it's still hot. If it stays wet, it's ok to touch.
  • When testing metal for heat with your hand, use your knuckles rather than your fingertips.
  • Hot pieces of metal that we're done with go underneath the forge. Always assume that anything under there is hot and treat it accordingly.
  • Know what metal you're putting into the forge. We have a lot of mild steel around the shop, which is fine. Heating galvanized metal can release fumes that will kill you. If in doubt, ask for help!
  • Never hammer on the anvil face when using a hot cut or similar tool in the hardy. You might hurt yourself or send something flying.
  • Make sure there's ventilation. Keep at least the front doors open when forging.
  • Know where the fire extinguishers are and how to use them.
  • Never forget that everything in the shop is designed to pinch, burn, stab, bruise, asphyxiate, crush, or cut you or others.

- Don't use the power hammer or the torch without taking the relevant auth classes.

Authorizations

The power hammer requires its own authorization class. The torch does too. Do not use these without being authorized.

Basic Tool Use

The Anvil

The anvil has several named parts, and different parts can have different parts. The common elements of the shop's anvils are as follows:

  • Face. This is the long horizontal surface that faces the ceiling. It's the primary surface you put metal on to hammer.
  • Horn. Also sometimes called the "beak" or "bick," this is the roughly conical shaped bit sticking off one end of the anvil. It's good for putting curves in metal and drawing out metal. Some anvils have a flat horn on the other end; this horn is not round but tapers down to a blunt point.
  • Hardy hole. This is the square hole in the anvil's face. Tools that can aid with things like cutting, bending, and otherwise shaping metal have stalks that fit into the hardy hole. Never have one of these tools in the hardy hole when not using them. Always remove them before working on the face of the anvil.
  • Pritchel hole. This is a round hole in the face of the anvil. Some anvils have more than one. They're used in the final step of punching holes in metal.
  • Edge. The edges are the long corners of the face of the anvil. If the anvil is situated in front of you long-ways from left to right, the top corner closest to you is the "near" edge and the one farthest from you is the "off" edge. There are some forging operations that work best if you do them on the near edge and others that work best on the far edge. If you move to the other side of the anvil, the near and far edges move along with you -- near is always the one closest.

The common wisdom is that the ideal height of the face of the anvil is where your knuckles hang by your side if you're making a loose fist. Different people have different preferences. Mostly you want the anvil face to be in a position in which your hammer blows will land perpendicular to the face of the anvil. This will give you the cleanest forging and reduce hammer gouges in the anvil face or your work. Forging on an anvil of the wrong height can lead you to have joint discomfort.

The Hammer

Different hammers are for different tasks. Sometimes a lighter hammer will be better than a heavier. Different shapes of hammer face are better for different operations. A hammer that has a flat face and a rounding face or cross peen are good first hammers.

Hold the hammer with the thumb around the hammer rather than on top. Choke up or don't, as you like. The hammer goes in your dominant hand, tongs or workpiece in your non-dominant.

Stand close to the anvil when hammering. This can help with accuracy and can also reduce shoulder and elbow strain. When swinging the hammer, try to keep your elbow tucked in close to your body and use efficient hammer strokes. Don't swing wildly or too high, as you might hurt somebody, ruin your own rotator cuff, or strike inaccurately and damage the anvil, hammer, or your workpiece. Remember that unless a particular technique calls for another approach, you want your hammer face to strike perpendicular to the anvil's face.

It's ok to hit the metal hard! Sometimes you need heavy hammer blows to move metal. Sometimes you need lighter blows instead. There are needs for both power and nuance in forging. But when it's time to hit the metal hard, swing and pretend you're striking through the anvil. Unless you miss the workpiece or hit the workpiece too cold, you're unlikely to hurt the anvil.

Indexing is a technique in which, instead of moving the hammer around to strike different spots on your workpiece, you keep your hammer oriented to a single spot on the anvil and move the workpiece under it. This can help you strike more accurate blows and work more efficiently. This technique can help reduce hammer marks in your work, if your accuracy otherwise isn't the best.

In general, don't strike metal when it's not a red heat or hotter (orange). You stand some chance of damaging your workpiece, the anvil, or your hammer. You're also mostly wasting your energy when doing this as well. The exception is when you are making softer blows to straighten a piece or "planishing" blows to to smooth out imperfections in a workpiece. You can always take another heat to get your metal back to a glowing orange. The metal will move more easily and you reduce your risk of introducing faults into the workpiece.

Other Tools

The shop has a variety of tongs. Some of them can be used for various purposes and some are more single-use. The most important thing is to make sure that. the tongs you use will hold the workpiece securely. If you use tongs that don't hold the piece securely, you can have flying orange metal in the shop or otherwise cause fear and injury.

We have several tools that are used in the hardy hole. The most frequently used in our shop are the hot cut and the guillotine (also known as the Smithin' Magician).

The hot cut looks like a blade curved upward to the ceiling once inserted into the hardy tool. Use this by placing only hot metal at the crest of the upward curve and striking it. It's best to use gentler strikes to cut the metal here; else you might cut right trough the metal and ruin the hammer face and hot cut by striking the tool with the hammer. Never use this tool when your metal cools below a reddish color. Cooler metal will chip the blade.

The guillotine enables you to pinch metal between two dies with roughly equal force and without needing a third hand. Insert the guillotine's hardy stalk into the hardy hole and secure it underneath with the nut and bolt. Once your workpiece is hot, lift the top die and place the workpiece underneath. Generally you'll want to hold your piece parallel to the ground and perpendicular to the faces of the dies. Then strike the top edge of the top die with the hammer.

We also have a variety of chisels, punches, nail header tools, a twisting wrench, saws, a post vise, angle grinders and a big belt sander. If you're unsure how to use any of these for a reasonable purpose or safely, please ask in the Blacksmithing channel on Mattermost or seek out a smith who can help you out.

Using the Propane Forge

Always insert flame into the forge before turning on the gas. If you run the gas first, you can make a fireball and a boom, which can be dangerous.

There's a high shelf in the corner of the blacksmithing building with a handheld propane torch on it. This is handy for lighting the forge. If you use this, please make sure to turn the gas knob all the way off once done.

To turn on the gas to the forge, turn the knob on the top of the propane tank. There's generally no need to turn the red knob on the regulator unless you want to change the PSI. We usually run at around 10 PSI, and there's generally not a need to go much higher.

When you're done with the forge, just turn the knob on the top of the big propane tank until the gas flow stops and the forge stops emitting fire. You'll be able to hear and see the difference.

Plan to stick around for about a half hour after you turn the forge off, to make sure it cools down a bit. Plan this time into your forge time so that you don't get in a hurry and need to leave prematurely.

If the flame dies while you're forging, you've probably exhausted a tank. We have three tanks in rotation and one usually has some propane in it. Disconnect the regulator (there's a wrench in the corner), carefully roll the empty tank on its base to where the spare tanks are and replace with a full one. Attach the chain around the new tank as it had been attached around the original tank. Don't over-tighten the regulator when screwing back in (also don't under-tighten it). If you're not comfortable doing this, mention in the Blacksmithing channel that the tank needs replacing and somebody'll take care of it when they're next at the shop.

Using the Coal Forge

If you know how to use a coal forge, just use it. Please make sure the fire has died down before leaving. We use a hand-crank rotary blower. It lives inside the blacksmith building and needs to be attached to the forge before use and unattached and stowed back in the building after. Please make sure any coal rakes or other tools go back inside the building when you're done.

If you don't know how to use a coal forge, please ask for help and someone can show you how.

Closing up Shop

Please try to leave the shop at least as clean as you found it. Throw away any beverage containers or other trash you bring in, and put any tools you got out back where they belong. If you see other things out of place, put them back in place. If you've generated steel scale or dust in any appreciable amount, sweep it out the front doors.

When you leave, secure the sliding front doors by sliding them closed, looping the chain to link them together, and latching the hooks in at the edges. Turn out the main lights using the switch by the door, and lock the side door before you leave.

Manuals