Ethnographic Arms & Armour - View Single Post - Sword Construction

A Senefelder · 11th April 2013, 01:39 PM

While I am an armourer by trade I have monkeyed with blade making a bit with some friends and spent a fair amount of time around some reputible blade smiths. This is actually technically a pretty complicated subject but i'll try to keep it simple. When a sword is swung and contacts a target stress is placed on the sword via kintetic energy. Much of the energy is transmitted to the target as , of course, was the intention but some of it travels both up and down the length of the blade. The energy/stress that travels up the blade to the tip is fairly easilly disperssed ( as long as the temper of the blade is good ) via the blade being able to flex back and forth until dispelled ( this can be seen quite graphically in slow motion ). The portion of the blade from the point of impact back to the tang is a different story. The hilt, especailly at the quillions is a shock trap, it stops the dissipation of that converted transmitted kinetic energy at that point rather sharply and can cause the tang to snap without special provisions. This can be achieved in one of two ways. 1) the blade is tempered, tempering is controlling heat in a set enviornment to molecularlly combine hardness and toughness in the desired ratios for the purpose of the object created ( a sword and a drill bit are not for the same purposes and require different ratios of hardness and toughness for thier purposes ). The tang can be tempered to a different level to be more tough than hard to sustain the shock of the force being trapped by the hilt. This can be very tricky to do. 2) An iron tang can be forge welded to a steel blade. Iron is very tough and cannot be tempered ( tempering is a function of having the right minimum amount of carbon content which iron does not ) thus the blade can be fully tempered without worrying about the tang being tempered wrong and risking breaking under sever impact. Forge welding can also be very tricky to do. A good forge weld is well neigh indestructible ( it is afterall pattern welded blades were made ).

I hope this makes sense.

11th April 2013, 01:39 PM	#2
A Senefelder Member Join Date: Jul 2009 Posts: 214	While I am an armourer by trade I have monkeyed with blade making a bit with some friends and spent a fair amount of time around some reputible blade smiths. This is actually technically a pretty complicated subject but i'll try to keep it simple. When a sword is swung and contacts a target stress is placed on the sword via kintetic energy. Much of the energy is transmitted to the target as , of course, was the intention but some of it travels both up and down the length of the blade. The energy/stress that travels up the blade to the tip is fairly easilly disperssed ( as long as the temper of the blade is good ) via the blade being able to flex back and forth until dispelled ( this can be seen quite graphically in slow motion ). The portion of the blade from the point of impact back to the tang is a different story. The hilt, especailly at the quillions is a shock trap, it stops the dissipation of that converted transmitted kinetic energy at that point rather sharply and can cause the tang to snap without special provisions. This can be achieved in one of two ways. 1) the blade is tempered, tempering is controlling heat in a set enviornment to molecularlly combine hardness and toughness in the desired ratios for the purpose of the object created ( a sword and a drill bit are not for the same purposes and require different ratios of hardness and toughness for thier purposes ). The tang can be tempered to a different level to be more tough than hard to sustain the shock of the force being trapped by the hilt. This can be very tricky to do. 2) An iron tang can be forge welded to a steel blade. Iron is very tough and cannot be tempered ( tempering is a function of having the right minimum amount of carbon content which iron does not ) thus the blade can be fully tempered without worrying about the tang being tempered wrong and risking breaking under sever impact. Forge welding can also be very tricky to do. A good forge weld is well neigh indestructible ( it is afterall pattern welded blades were made ). I hope this makes sense.