How to Weld

In a post-apocalyptic world, scavenging is the order of the day and you’ll likely be able to find plenty of scrap metal lying around (or still attached to something that nobody is using).  That metal could be useful by itself, but it might be more useful if you could weld smaller pieces together to form one large structure.  Plus, knowing how to weld is a skill you can trade on, unlike that Cisco certification you spent thousands of dollars on.

Fundamentally, welding is a simple process – heat two pieces of metal until they’re nearly liquid and force them together meshing one piece to the other.  Most of the time, a filler material (commonly a more maleable, and thus easier to liquify metal than the one being welded) is used to aid in creating a cohesive bond, or joint, in the metal pieces.  Over the years, industrial welding has evolved into a futuristic world of laser welders and using ultra sonic waves to fuse molecules together, but these types of welders are crippling expensive and rare, and thus you are unlikely to have access to them after The Event.  For our purposes, there are three types of welding: forge, torch, and arc.

Forge welding is the most primitive form of welding.  To forge weld, you heat the two pieces of metal until they are red hot, but not liquified. Place them on an anvil with one piece slightly overlapping the other and hammer them back down to the thickness of either piece of metal and thus forcing a mesh of the two pieces.  Don’t expect this technique to work on steel, it will only work on more maleable metals that approach or cross the liquification point in forge temperatures (think bronze, copper, iron, etc).

The next step up is torch welding.  To torch weld, you will need a torch – the most common torch used in welding is an acetylene torch, which is essentially a nozzle that mixes pure acetylene with pure oxygen, which you light as it comes out the end.  An acetylene/oxygen flame burns at over 3000 degrees celsius which is the hottest flame you will get from readily available combustible gases.  If you are making a makeshift torch, you can use any pure combustible gas and you can use compressed are instead of oxygen for your oxidizer, but you won’t achieve the same temperatures as your would with an acetylene/oxygen mix.  Also, you need to make sure you are using some sort of non-return valve in order to ensure that you and your fuel cylinder don’t go up in flames while welding.

To perform a torch weld, place the two pieces of metal firmly together, turn on your acetylene just enough so that you hear gas escaping.  Light the torch and adjust the acetylene until the flame is barely coming out of the nozzle.  Turn on the oxidizer slowly until the flame turns blue.  Point the flame at the joint and move the torch in a circular motion until the metal begins to melt.  If you are using a filler rod, you can insert it slowly into the pool of molten metal to add more to the pool.  Once you have a large enough pool, begin moving the torch slowly down the seam.  If you go too fast, you will run out of molten metal.  If you go too slow you will have too much.  If you are using a filler rod, you will want to keep it in the hot zone of the torch (not close enough to melt it but not far enough that it cools off) to prevent a weaker “cold” weld.  Turn the torch off in the reverse order you turned it on.

The final type of welding you should be familiar with is arc welding.  Arc welding uses electricity to heat metal instead of flame and in this case, you NEED a filler rod.  An arc welder is essentially a placeholder for your filler rod that is attached to a power source.  As electricity passes in an arc from the end of the filler rod to the seam in the metal, it generates a great deal of heat, melting the rod and the metal equally.  There are hundreds, if not thousands, of different types of filler rods available.  Each one has a special purpose it was designed for, and sometimes you’ll need a certain type of rod to do any kind of welding on a certain kind of metal.  We won’t get into that here, just be aware that this is a consideration if you have access to an arc welder post apocalypse.

To perform an arc weld, the first thing you need to do is attach a grounding clamp from your power source to your metal.  This is important because if you don’t do this, the all-important arc will not be generated in order to heat the metal.  To initiate the weld, or “strike the arc,” tap the end of the filler rod against the metal and then hold it at approximately 1/8 inch above the metal.  You will see copious sparks shoot up from the metal – this means you got an arc.  Angle the welder into the direction of movement at approximately 45 degrees and equidistant from each piece of metal (this is important if you aren’t welding two flat pieces of metal together), as if you were dragging the tip of the filler rod along the surface of the metal.  Slowly move the rod across the seam until the joint is complete.

That covers the bare necessities of welding.  These procedures and techniques will get you by in a situation where you need to weld.  There are dozens of advanced techniques on how to weld in different situations, for different types of metal that I haven’t covered here.  Just remember that practice makes perfect, and if you need to weld something intricate “measure twice, weld once.”

How to Fashion a Make Shift Knife

In a survival situation, a knife can be one of your most important tools.  It’s a weapon and an eating utensil.  You can cut rope with it.  You can dig with it.  You can peel bark from a tree to use as fire fuel.  You can skin an animal with it.  It’s a very verstile tool that can come in handy in any number of situations.  You should keep one in your Go Bag, but for some reason or another, if you lose that knife I’m going to show you how to manufacture a field expedient knife to use until you can get your hands on a new knife or can forge yourself a new one.

First of all, a knife performs three basic functions: piercing, slashing, and cutting.  Ideally, a knife will do all three, but in some cases a field expedient knife will only ever be able to do one or two.  You can fashion a knife out of all sorts of material: metal, wood, stone, bone, glass, plastic…  It all depends on what you have available.

Metal

Your obvious first choice for a knife material, metal is going to probably be scarce and especially metal that is small and thin enough to be used as a knife.  However, if you’re lucky enough to stumble on a piece you will be able to fashion a knife that will last you a very long time and that you can resharpen.

If you don’t have tools to work on it, most metal is nearly impossible to manipulate.  So if you can’t find a piece that is pretty close to what you want you might not be able to make a knife.  You can try hammering the piece into the shape you want, but this will only work on soft metals.

Once the rough knife is in the general shape you want, you need to sharpen the edge.  This can be accomplished by running the edge across any rough surfaced stone (including pavement).  You will get a better effect if you get the stone wet before attempting to sharpen it.

If you want to get a REALLY sharp edge, rub the edge of your knife on unpolished ceramic.  If you look at the bottom of a coffee cup, you’ll notice that rough ring that the cup sits on.  That ring is unpolished ceramic and will even sharpen forged knives, including the knives you have in your kitchen right now.  Yes, this tip applies to non-survival scenarios too!

Stone

Stone is one of the most reliable and sturdy materials to make a knife from.  Since its such a sturdy material, you will need a couple of specialty tools to make the knife:

  • Chipping Tool – a chipping tool is a blunt tool used to break off pieces of stone
  • Flaking Tool – a flaking tool is pointed to break off flat pieces from the stone

The first consideration you need to make is the actual stone you will make into a knife.  You need to use a soft enough stone that you’ll be able to carve it with your tools.  Secondly, it’s totally up to you how long you want the blade, but you need to account for a handle or a tang to attach a handle.  If you can find a rock that’s already close to the shape of a knife you;re in business.  If worse comes to worst, you can use your chipping tool on the edge of a boulder and try to knock a piece loose to make a knife from.

Get the general shape of your knife using the chipping tool.  Strike your soon-to-be knife with one end of the chipping tool repeatedly until the knife holds the desired shape.  Try to keep your knife relatively thin – the thinner it is, the easier to get a sharp edge.  However, don’t get it too thin or else you run the risk of the knife breaking under stress.

The flaking tool requires a little more finesse.  PLace the flaking tool against the knife near the edge and apply pressure until pieces break off from the knife.  Don’t press too hard, or you could end up break off a chunk of your knife that you didn’t want to lose and it won’t have a sharp edge to it.  Continue doing this down the length of one, or both, sides of the knife until you have a blade edge.  Make sure to leave enough unsharpened length to be the handle or tang.

If you choose, you can attach a seperate handle to your knife.  Just tie a piece of wood or some other material to the base of the knife.  Make sure to secure it tightly or else you’ll have problems with the handle coming loose later (which could in turn cause injury).

Bone

Bone is a step up from wood, but it isn’t going to be as easy to find.  So given the choice between the two, go for bone.  Your first consideration is the size of the bone.  If it’s too small, you won’t be able to make a knife out of it.  To make a knife out of bone, you’re going to shatter the bone so a larger bone is going to create more shards.  Once you’ve found a suitable bone, place it on a hard surface and smash it with something heavy like a rock.  Go through the shards and find one appropriately pointy with the potential for a sharp edge.  Sharpen the edge of your shard against a rough surface (like cement).  Don’t forget to leave a portion unsharpened as a handle or tang to attach a handle.

Wood

Wood is easily the most abundant resource you will find in most of the world.  Unfortunately, it doesn’t make for an ideal knife-making material.  If you make a knife from wood, you will only be able to use it to puncture things and the point will go dull fairly quickly at that.  If you look at a piece of wood, you can see the grain is either straight or in a circle.  The straighter the grain, the further from the core of the branch/tree the piece is.  If there is no grain, it means the piece of wood is from the pith (the layer of wood seperating the tree from the bark).  You want to avoid wood that is from the core of the tree/branch and you want to avoid pith.  Both types of wood are weak and will crumble or snap if used as a knife.  Select a piece that’s roughly a foot long and shave the tip down to a point using a rough surface (like cement).  Once you’ve sharpened the point to the desired point, place the blade over a fire and let it slowly dry until it is lightly charred.  This process is known as “fire hardening” and will make the point hard and it will take longer to dull.

Bamboo

Fashioning a blade out of bamboo is very similar to wood.  However, bamboo is capable of holding an edge.  When shaping the knife, remember that the hardest part of bamboo is the out shell so try to keep as much of this layer as possible.  When fire hardening bamboo, only char the inside

Glass

When glass is broken, it naturally make a sharp edge so it is ideally suited as a knife.  Unfortunately, glass is incredibly brittle so you can’t use it for heavy duty work.  All you need to do for a handle is wrap a piece of cloth around the base of the shard.

Ceramic

The ceramic used to make coffee cups is similar to glass so in a pinch you can break a coffee cup and use the piece attached to the handle as a knife.

Plastic

Have you ever stabbed yourself while trying to open up a new piece of electronics?  If not, you’re lucky but if so you are painfully aware of how effective plastic can be as a knife.  You can also sharpen plastic—if it is thick enough or hard enough—into a durable point for puncturing.

Further Reading