Sir William the Brave said:
I don't know if this true or not but I heard that you can forge a sword by pouring the melted metal into a block.
But from my knowledge by watching a man forging a sword in youtube. I think the technique above must been around 18-19th centuries. Rather than Middle age.
Casting a sword by pouring into a block is absolute fiction.
Except for bronze swords, between 3000 and 600BC; those you do cast in a mould.
for a steel sword, however, casting is a complete fantasy, and utterly impractical, for a whole host of reasons. the biggest of those is simply that the medieval forges were not capable of getting hot enough to melt steel to a liquid - you could get it hot enough that you could move it around under a hammer, but you cold'nt pour it. The best you could do for poured metal was cast iron, which is liquid at a lower temperature, but cast iron is a terrible, brittle material for blades - it would just break if used for that.
the only way to make a sword* is through forging, heating up the metal to a glowing red-yellow heat, and hammering it out from the rough block into a blade shape.
basic processes for making a swordblade are:
smelting: a large volume of iron ore is placed into a bloomery - a sort of kiln-like furnace where the iron is extracted, as a spongy metallic mass called a
bloom.
that is then refined in a finery, a process of heating and hammering out to convert the spongy metal into a bar of iron, and squeeze out as much as possible of the impurity.
Iron containes carbon in its molecular structure - too much carbon makes pig iron, or wrought iron. too little makes a pure iron, which is of limited use too. but a small amount of carbon makes the iron struture much stronger and harder - what we call steel. Medieval smiths did'nt realise this however, and instead thought that steel was a purer form of iron.
So, the iron bars would be
Carburised in a funace, heating them up to burn away some of the carbon content, and working them into
steel This si a time-consuming process which made the steel much more expensive than the simpler-to-make wrought irons that have not been carburised.
These steel
ingots would then be sold and exported from the foundries. Steel ingots are a very valuable resource in the medieval age, and were used very sparingly - a knife, for example, would be made from a cheap iron back, with a small strip of steel forge-welded onto it for the cutting edge, saving the amount of steel used.
Good steel ingots would then be bought by the blade-makers from the foundries, to be used in production of blades. In medieval europe this was done in a number of areas - particularly the cities of Solingen and Passau, but also in areas like Brescia in Italy, and later on Toledo in Spain. The secrets of bladesmithing were guarded jealously and passed on amongst guilds of swordsmiths and
cutlers (who made knives). the average blacksmith in a village simply did not have the skills to make swordblades. The guilds vigorously protected the right to produce blades as a monopoly, and would come down heavily on any rivals trying to get in on their territory. Like the armourers, the cutlers and swordsmiths were not the lone blacksmith of fiction, hammering away by hand in thier lonely smithy. these were large factories with hammers and forges powered by waterwheels connected to belt-driven wheels and bellows, and churning out dozens of blades every day.
These blades were shipped out along the rivers to the whole of europe, where they were then hilted up in local popular fashions. Mass production is not a modern concept at all. Italian armourers of the 15th C were producing equipment on production lines where the only difference to what Henry Ford made up 400 years later was that instead of a conveyor belt, the peices were moved by hand by the apprentice boy...
But, assuming for narrative, you've got a one-off blade being made, this is the rough process.
the blade starts as an
ingot or
billet of steel - perhaps 20cm long, by 5cm wide, by 5cm thick.
that gets popped into a forge, and heated till it glows, and then hammered, usually either by a power hammer - a huge water-wheel driven hammer, or by a team of two or even three people with heavy sledges - the master would hold the billet in tongs, and would move it around, while his assistant(s) or apprentice(s) would swing the hammers to pound it out.
that process would see the ingot slowly shaped out, making the billet longer and thinner, a process called
drawing out that drawing out would slowly shape the blade into a long, thin bar of steel. at that point it would start to be profiled, shaping it more to become a blade-like shape. at the same time the
tang would be forged, where the blade's shoulders were shaped and the long stalk which would become the handle was drawn out.
at that point, the blade's
taper would be forged into it, making it narrower towards the tip, and moving mass away from the end. at the same point, the start of the cross-section of the blade would be worked. in the 15th C that was most commonly a diamond section - sort of a <> shape, with a strong mid-ridge that made the blade stiff. some blades, particularly those being designed for the cutting of unarmoured targets would be forged with a broad groove down the middle, called the
Fuller. This would be done by using a special tool piece added onto the anvil called a swage block, and a profiled hammer, to forge in the basic line of the groove along the blade.
when this was done, you have a forged blade shape, black from the forge, that's pretty much the shape of your blade.
this would then be heated up till it was a consistent glowing yellow heat, and then pulled from the forge, and
quenched in a liquid - usually water or brine, but sometimes oil, and in the medieval era, perhaps something more exotic - with the science behind it being unknown, the process was somewhat mystical and secretive, so other material might be used. despite what "conan" showed, snow is'nt a very good quenching material - its actually quite a good insulator, so does'nt work. The quench was done to cool the blade down rapidly - a secret of the swordsmith's art for making hard blades that a common blacksmith was unlikely to be aware of. The result of a quench is to change the molecular structure of the blade, making it extremely hard. However, with hardness the blade can become brittle, so the second step was to make it softer and more springy, and less likely to break. This process, of
tempering the blade would be done by cleaning up the blade to remove the black fire-scale that had amassed in the forging process, leaving clean metal. it would then be slowly heated up again, to a lower temperature, and then left to cool back down naturally. there were a number of ways that this could be done - it could be returned to the forge, and gently heated so when the metal sharted to change colour from metallic silver, to a brown, and then a vivid blue tint, it could be withdrawn from the heat and left to cool - or for blades with fullers, two small bars of metal could be heated till they glowed, and placed below and on top of the blade, to conduct heat into it from the middle of the blade, and again, left to cool. Either way, the resultant blade would be more springy and less brittle, making it more usable as a weapon.
this blade blank would then be ground on a grindstone - a large 1m diameter wheel, sometimes water-powered, sometimes hand-cranked by the poor assistant, which would run through a trough of water to keep the stone and the blade cool. it would then be
ground, and slowly shaped from the blade blank into a fully made blade. it would be rubbed with pumice stone to smooth the surface out further, and then with powdered pumice till it eventualyl became a polished gleaming blade.
the blade would then be either sold and exported by a merchant to another part of the world, or if being made there, would be handed off to another craftsman, the
cutler, who would make the
hilt parts -in a european sword, consisting of the cross, hilt and pommel, to protect the hand, to grip, and to counterbalance the blade respectively. Those would be made according to local fashions of the customer - would prefer different shapes, or proportions. They would normally be made by forging iron ingot peices, drawing out to a bar for the cross, and peirced with a punch to fit down the tang, then shaped by files and forging to fit exactly. The hilt would be made from hardwood - beech, ash, or poplar, either bored through with a hole, and then burned out to match the shape of the tang, or carved out of two peices to fit around the tang. that would then be carved and worked to shape for the hand and then bound in fine cord, then wrapped in thin leather. the pommel would be worked at the same time as the cross, shaped by forging, and then peirced with a drift, shaped to match the tang.
the whole thing would then be peined over, heating the end of the tang to allow it to be locked toght like a rivet.
at that point, you've got a sword. That's before you go into the woodworking and leather coverings for a scabbard and swordbelt you'd also need.
See why they were often quite high-status equipment, with all the work that goes into making them?
*at least, using medieval technology. nowadays, you could make it by grinding from a billet of steel - but even that's been shaped out by huge heavy rollers, which do the same sort of job as a forging hammer would've done before.