5
$\begingroup$

I have in mind a bladed weapon that, left unpowered, looks like a "regular" sword, from whatever time period. The appearance of the weapon is important to the story; people need to know that it's a melee weapon on first sight, and able to use it without having to learn any exotic skills. It may or may not need to be obviously special to look at, but it is made of a substance of about half the density of steel, and is significantly tougher. It will therefore be substantially lighter than any common weapon, and more readily balanced. I assume that, with respect to weight and balance, this sword is already optimized.

When connected to an appropriate power source, however, the edge becomes as sharp as the plot requires. No, it's not Infinitely Sharp, and will not plunge unstoppably into the core of the earth. But it will defeat any kind of commonly available armour, and shear through normal weapons and most barriers with ease.

My question relates to the shape and size of this kind of blade. Since penetrating power is no longer a requirement, what will guide the shape and size of this weapon?. Is there a shape or size this sword could be to take advantage of its cutting properties? Conversely, is there some shape or shapes that this sword cannot be because of those same properties?

$\endgroup$

closed as primarily opinion-based by Mołot, Hohmannfan, Frostfyre, Skye, Aify Sep 14 '16 at 17:57

Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise. If this question can be reworded to fit the rules in the help center, please edit the question.

  • 8
    $\begingroup$ The 'best shape' for sword depends on the fighting style of the person wielding and the conditions it is intended to be used in, it there is not one best shape. A short cutlass type weapon was good for close fighting onboard a ship for example where you could not swing a larger weapon without catching onto the internal structures of the ship. $\endgroup$ – Sarriesfan Sep 14 '16 at 11:34
  • 8
    $\begingroup$ If the edge can cut anything with no resistance, shape no longer matters. Not for cutting power, anyway. $\endgroup$ – Mołot Sep 14 '16 at 11:34
  • 5
    $\begingroup$ I just realized that if it can cut through anything, you could drop it and it would cut it way to the core of the earth right? $\endgroup$ – Skye Sep 14 '16 at 12:26
  • 8
    $\begingroup$ Keep in mind that it's dangerous to use this sword to block; if you cross blades with a regular sword, half of it will be cut off and continue flying towards you, doing lots of damage if you are unarmored and/or it was swung with enough force $\endgroup$ – Annonymus Sep 14 '16 at 12:42
  • 7
    $\begingroup$ Well, it'll drop all the way to the core if it's all that sharp. Most swords include a handle, because 'holding the sharp bit' isn't all that great. And the handle would stop it dropping to the centre of the earth. $\endgroup$ – Sobrique Sep 14 '16 at 15:42

11 Answers 11

15
$\begingroup$

I kind of disagree with some of the other answers and comments. The form of your sword is not primarily determined by fighting style or purpose. It's dictated by armor and enemy weapons.

The curved form of sabers was introduced because it would maximize cutting power against largely unarmored or cloth-armored infantry, and to thrust around shields. (edit: also so the mounted warriors wouldn't get their blade stuck while riding by....)

The Zweihander and Claymore swords were introduced to scare off enemies and to break enemy close formations.

The cutlass was the primary weapon aboard ships because the enemy was largely unarmored, it was cheap to manufacture, and there wasn't enough space on a ship to swing wildly with your Zweihänder.

The whip sword was only effective in areas where armor was basically unknown.

And finally, even though i know i am entering thin ice here, the katana proved successful, because the Japanese didn't have metal armor, and a fast, sharp, cutting weapon proved most effective against most common opponents.

The combat "styles" developed together with or after a weapon was introduced. People would invent a weapon, test in in training fights, find a good way to fight with it, test it out on the battlefield, and then the weapon would start spreading if it was considered supreme.

Now, a sword that can cut "anything" means your opponents armor doesn't matter. Your opponents weapons don't matter. Your opponents shield doesn't matter. Basically, it's all about what shape gives the user most control over his blade. That is to improve the speed of his moves (because he can literally cut anything, he also doesn't need much FORCE in his attacks, so he can focus on speed). And to reduce the risk of self-injury.

Even though i am not a fan of japanese weaponry, being a HEMA fighter myself, I think the katana proves to be perfect for this scenario. you do not need a guard, because the enemy sword will cut through it. You don't need force, so go for a light blade. And it's 1,5 handed, allowing for maximum control and flexibility.

Also, there already IS a historical and pretty well-developed fighting style, saving a lot of work developing a new one.

$\endgroup$
  • $\begingroup$ Consider the Tulwar, which is actually famed for it's cutting power: youtu.be/2BoKUfaorJ0. It will also be lighter than a katana, which means more speed, which means more advantage from that infinite cutting power. $\endgroup$ – PipperChip Sep 14 '16 at 15:35
  • $\begingroup$ Um, your opponent's weapons still matter. There's nothing in the question stating that the sword also magically makes your body impervious, or magically automatically parries all incoming melee weapons or projectiles. And, unless you're making a lightsaber, that is, a sword that cuts in all directions, that implies that there is some surface on the blade that does not cut. An opponent could take advantage of that surface to parry with their weapon, or even, though probably at much greater difficulty and risk, with their shield or arm. $\endgroup$ – 8bittree Sep 14 '16 at 16:29
  • 1
    $\begingroup$ Shadiversity did a whole series on Katanas and them as cutting weapons. they're good but Falchion, as he points out, is pretty much the European version and is superior in almost every if not every regard. So nope no katana ^.^ and i love katanas $\endgroup$ – Durakken Sep 14 '16 at 16:48
  • $\begingroup$ This honestly makes me think a Whip like sword would be very powerful here. Its major weakness is the lack of force on the blade itself, but if it just kept going through armor as if nothing was there thanks to its ability to cut anything, it would slice the armor in half, wearer included while they could never get close. its length means a twirl keeps all melee weapons but possibly halbards and such from reaching you. $\endgroup$ – Ryan Sep 14 '16 at 18:08
  • $\begingroup$ I find your opening statement contradictory. The form of just about anything is determined by its purpose, otherwise known as its function. In this case, that purpose is in turn determined by factors such as enemy armament and environment, as you so ably point out. In what way is this answer in disagreement with other answers that base themselves on the same factors? $\endgroup$ – Lord Dust Sep 14 '16 at 18:40
5
$\begingroup$

I think you will see the same variety of blade shapes as you see today: the shape of any blade will be defined by the purpose. If you want a lot of reach, you will have a long blade, like in a Zweihander or Claymore. If you want extreme precision, you will get a scalpel.
The only difference will be that you don't need wave or tooth patterns on the blade's edge anymore.

$\endgroup$
  • 2
    $\begingroup$ Using a scalpel that can cut through anything in surgery would be terrifying. 'Oops, I dropped my scalpel, it went right through the patient and table, Is he still alive?' $\endgroup$ – Skye Sep 14 '16 at 12:25
  • 2
    $\begingroup$ I would assume it has a safety button where you have to keep pressing it to have it be able to cut through everything $\endgroup$ – Fox-Chan Sep 14 '16 at 13:19
  • $\begingroup$ A dead man's switch would definitely be a good idea for a surgeon's scalpel. $\endgroup$ – Burki Sep 14 '16 at 14:01
  • 1
    $\begingroup$ @Sky And what exactly are you trying to cut through during surgery that a regular scalpel won't cut? $\endgroup$ – Michael Sep 14 '16 at 15:13
  • $\begingroup$ @Michael Samus Aran's armor? $\endgroup$ – JAB Sep 14 '16 at 16:06
3
$\begingroup$

For something to be able to cut through anything, the only concept that fits is the science fiction concept of a monomolecular filament, typically made of carbon nanotubes. This can be seen in many works of fiction, including the Molly Fyde series by Hugh Howey. In many of these cases, there's a power source connected to something generally dissimilar from what we think of as a sword, but wielded in a similar way.

The sci-fi theory behind such a "blade" is that the single molecule filament is able to cut through any object by means of sliding between and dissociating molecular bonds in solid objects.

Any conventional blade will have restrictions which cannot reasonably be overcome. Even something like a Vorpal blade from Dungeons and Dragons (originating from Lewis Carroll's Jabberwocky), which is preternaturally sharp, still cannot cut through absolutely anything, though it has a penchant for decapitation.

$\endgroup$
  • 1
    $\begingroup$ A monomolecular Filament wouldn't cut anything. It would pass through without damaging anything. The wedge shape is what does the damage of separation. So if you have something flat it doesn't really do anything. $\endgroup$ – Durakken Sep 14 '16 at 16:53
  • $\begingroup$ I did specify that this was science fiction, but this concept has been used in sci-fi universes many times. Also, the wedge shape of a sword isn't to make it cut better, it's to cause more damage (while different, bullets and ballistics have similar concepts to this). This is why there's only a very marginal "wedge" to something like a steak knife. And really, even there it's only to keep it from being too brittle to use - the wedge isn't a necessity for cutting at all. Water cutters prove that out. Heck, you don't even need a physical medium - laser cutters. $\endgroup$ – Jesse Williams Sep 14 '16 at 19:45
  • $\begingroup$ Wrong. The wedge is there to spread. Water uses high pressure to force molecules into the space in between the other objects molecules and spread them apart. This is what the wedge does for blades. The edge of the blade for cooking knives aren't very sharp because they don't need to be. and likewise scalpels only appear to not have much of one because it is distributed across the whole of the blade. Lasers don't actually "cut", they burn precisely and cause other reactions to occur. $\endgroup$ – Durakken Sep 14 '16 at 19:54
  • 1
    $\begingroup$ Ok, I'll bow out of this because you're arguments aren't rooted in reality. Scalpels and razor blades are EXTREMELY sharp, without a need for breadth to "spread" things. Cooking knives ARE very sharp. In fact, safety requires a kitchen knife to be sharp - dull knives are more dangerous to use. As for edges and wedges and breadth, clearly you've never had a papercut. Paper is neither sharp (technically), nor wedge-shaped, but it can still cut without having to "spread". The spreading effect of a sword is specifically to inflict more bodily harm by giving up wieldability. $\endgroup$ – Jesse Williams Sep 14 '16 at 20:02
  • $\begingroup$ You failed to read v.v Scalpels are sharp and it's because they thin and have a wedge. Just most people don't notice it because it so accute. Kitchen Knives are sharp relative to normal sharp vs dull, but not in an absolute scale. As far as Paper. The wedge enhances the effect of the thinness of blade, the paper in this cases. You're pushing the molecules into the molecules of the other object. The wedge pushes the parts apart. A filament is flat and could pass through another object without touching other atoms, making it not actually able to cut. $\endgroup$ – Durakken Sep 14 '16 at 20:22
3
$\begingroup$

We're making a couple of assumptions here, but the main issues with swords have always been reach, cutting power, and weight/balance. Now, reach is obviously a good idea, assuming you have enough space to use it effectively. However, swords with a long reach have traditionally been very heavy and in many cases, badly balanced. (The pommel in the hilt of a sword is there for this very reason.) The extra weight has been to some extent offset by the increased kinetic energy the weight provides, but fatigue remains an issue. The exceptions to this rule are katanas and their larger cousins, the nodachis, which are, in the context of swords, quite thin and use an entirely different fighting style, thus further mitigating the balance issue.

Cutting power can be safely ignored, since your technological device handles that.

The weight issue is partly negated by the lighter materials, but the balance issue remains. Either you will need to employ counterweights in the style of medieval swords, use a shorter blade or something with a very thin blade, such as a katana. The issue with thin blades is that they are more prone to breaking if handled wrong, and they must be constructed partially of a fairly flexible material (in the context of metals), since harder materials tend to be brittle and prone to breaking. Katanas are often constructed of three different types of steel with varying hardness, achieved by controlling the ratio of carbon to iron in the steel. This is something that should be taken into account as a katana made out of only hard metal would most likely break quite easily due to it being fairly brittle.

The last issue is reach. Unless you plan for the weapon to be used mostly indoors or other very cramped environments, I would recommend first and foremost a katana-style weapon, since they tend to work well even without a counterweight, thus making for a lighter, more balanced weapon. If you want a more sci-fi looking sword, a bastard sword -style weapon might be a suitable compromise, although in terms of performance it will most likely remain inferior to katanas.

$\endgroup$
2
$\begingroup$

Honestly this shape would be determined on how your society is shaped, what would their armor look like? Religion? Social status? as well as what does your opponent's armor look like? what are its weaknesses? Assuming there is a protection against this technology what is the best way to counteract it? Without this information I can't answer the question to the extent I could if I had it. The best way to utilize this technology in my opinion its to be able to cut and stab your opponents from a distance, so I would suggest spears, or maybe crossbow bolts with this tech inside it if that would be possible. The spear should be able to slice as well so I would stay away from European styled spears and go closer to Asian styled slicing, and stabbing spears.

for example

$\endgroup$
2
$\begingroup$

You DO want a Curved Blade

I originally wrote a long answer predicated on the idea that you want to eliminate curved designs to shift the point of control back towards the handle, but as I reached the end I discovered I was wrong.

Curved blades were design to increase the momentum of the tip of the sword, allowing deeper cuts. You don't need any help to make deeper cuts, but that momentum is going to allow you to continue your slices more fluidly. If we shifted momentum back down the blade with a straight design, the effort involved with going from Person A to Person B increases somewhat - but a weightier (curved) edge would give you faster and more fluid motions.

As others have noted, you should also make do without a guard because it's simply not needed for hand-to-hand combat when your sword will cut through your opponents. Unless supersword vs. supersword means that you WILL parry as per usual, in which case bring it back.

Blade and handle length is relevant only to the characters in your story. If the blade is long they would probably appreciate a two-handed handle design though, just to improve stability and control. With that said, don't forget that your blade is quite light, so you can probably have a longer 1-handed sword than what you traditionally see here on earth.

.

But don't forget the Rule of Cool

Cool blade

Sometimes the best literary weapons are those that see the coolest, even if they aren't the objectively best weapons. I would personally submit a very modern sword for such a bill, staying very flat all the way along. It's not perfect, but it's very easy to explain or assume that the technology that produces the supercut field operates symmetrically and so curved weapons are out.

$\endgroup$
  • $\begingroup$ I disagree about the irrelevance of a guard. For one thing, it can prevent your hands from slipping up. Secondly, unless your sword is just a wire, there's a couple sides and possibly a back that your opponent's weapon can safely hit and slide along. Parrying with the cutting edge is a bad idea anyway: with normal swords, it damages the cutting edges; with this super sword versus a normal sword, you run the risk of the former tip of your opponent's blade flying into your face and/or a clever opponent taking advantage of the fact that the remains of their weapon are now inside your defenses. $\endgroup$ – 8bittree Sep 15 '16 at 14:47
  • $\begingroup$ @8bittree - A bit of a flare to prevent your hand going up isn't crazy, but it doesn't necessarily have to be a "guard" (preventing the other sword from hitting yours). I am assuming that your opponent also has a supersword, so a guard is useless if they slice right through it. I postulate that sword fighting with these would be a generally poor idea in the first place, with so many opportunities for both parties to just die. I doubt most parrying would be an effective/useful act in such a fight, as a wrist-movement on your opponents side kills you instantly. Personally, I'd bring a gun. $\endgroup$ – GrinningX Sep 15 '16 at 15:22
  • $\begingroup$ Yeah, I suppose if everyone's got super swords, guards probably would become pretty minimal. But the way the question's worded, it sounds like more conventional weapons might still be common. And yes, Indiana Jones is absolutely the way to go when confronted with one of these. $\endgroup$ – 8bittree Sep 15 '16 at 15:36
1
$\begingroup$

If it's light enough, a weapon similar in shape to a sweeping brush with a long handle would probably be good. The edge of the blade would point away from the wielder.

The weapon needs only a light force to cut, so you don't need the fast slashing movement of a sword - so why let your enemy get within sword-range of you?

A phalanx of T-spear armed units could (ahem) sweep your enemies away, and you would probably need only a single rank (apart from reserves). OK it's a bit less maneuverable, but unless your enemy can fly to get around you, that would seem to matter little...

Your cavalry could mow down the enemies with really wide versions as soon as your enemy learns their lesson and decides never to engage in hand to hand combat.

$\endgroup$
  • $\begingroup$ Indeed...why not go with a naginata instead of any kind of sword. You keep out of range of them and you can cut everything $\endgroup$ – Durakken Sep 14 '16 at 16:50
1
$\begingroup$

I'm guessing a monofilament of superconductive material about 8 light minutes long, attached to two spaceships one on each side capable of near-lightspeed acceleration. The superconductivity will be critical for cutting through stars, with sufficient length to bleed off heat even when cutting a red super giant star. It probably can't cut a black hole but I think it handles everything else.

You did say anything.

$\endgroup$
  • 1
    $\begingroup$ "Cutting through stars" makes about as much sense as cutting through water does. They don't have any tensile strength, or rigid structure you could cut apart. $\endgroup$ – Henning Makholm Sep 14 '16 at 15:38
  • $\begingroup$ They're still splittable into two chunks. And planets or any other megastructure would be outside the range of a hand-held blade. $\endgroup$ – SRM Sep 14 '16 at 17:10
1
$\begingroup$

I would say it is like a string but not wool or anything, superthin iron in form of a straight string.

With a blade there is a problem. For example you would cut wood with a saw, it can cut wood but sometimes it get stuck.

So if you have a new iron or something like that which would never bent even it is so thin like a string, then i could imagine it can cut trow anything. Also it have to be super sharp.

Also imagine two swords collide in a fight with a blade i just can imagine the other sword to break because first the sharp front of the blade would make a cut into the other sword but the remaining part of the blade is not sharp so it would just break throw depending how hard you hit. But with a super sharp string i can imagine cut through the sword.

$\endgroup$
  • 1
    $\begingroup$ Welcome to the site, Xxy. Please note that the Worldbuilding SE is dedicated to detailed answers, rather than one-liners. If you would edit your post to indicate how iron in string form would be suitable as a weapon, and how such a construct would be the ideal structure for the OP's purpose, the community would appreciate it. Otherwise, this is likely to be deleted as inadequate. $\endgroup$ – Frostfyre Sep 14 '16 at 15:09
  • $\begingroup$ In other words (of the comment above), just add more text - flesh your answer up to contain more info. $\endgroup$ – RudolfJelin Sep 14 '16 at 15:38
  • $\begingroup$ The asker specified that the weapon should be in the form of a bladed weapon, which a thin string is not. Do you want to rework your answer? $\endgroup$ – rek Sep 14 '16 at 17:40
  • $\begingroup$ Thanks for the advise and for the nice welcome i will edit what i mean. $\endgroup$ – Xxy Sep 15 '16 at 6:24
1
$\begingroup$

The ability to cut is determined by the angle of the wedge that makes the edge and it's smallest point, the materials the blade is made out of, and the force applied to the blade.

Hypothetically a flat chunk of jello can cut anything if you apply enough force to it. The reason it doesn't work is the forces acting on the material make it break up before it can do it. The Smallest point is the biggest point that has to get between the points on the other object, and the wedge is just how smooth and thus how much force is needed to push more of the material between the other material.

So there is no "ultimate design shape". If you could you'd want to just make Free Quark edged sword with an infinite gradient bevel to human sizes made out of the densest material in the universe equipped with an anti-gravity field to counteract the weight.

But you want shape... so, basically you want a straight blade always, because curves weaken the blade and as such make it easier break and lower it's overall threshold for actual cutting ability. Curvature of the blade is for depth of cut, not cutting ability. The more curved (to a point) a blade is the longer the cut is, because more of the blade is in contact with and passing through the area as it is going through the same motion for the wielder.

a slightly curved blade, like the Katana, maybe helpful in drawing the blade and inductive to certain styles of fighting, but it's overall a weaker blade in many respects due to that slight curve and the disadvantages outweigh whatever slight advantage that curve brings.

The more curved the blade is the more unwieldy it is to sheath and use in various other respects than just straight cutting so even though a greater curve causes a longer cut, I'd consider it a worse overall sword in general because it loses all those other things and is harder to sheath than a normal sword.

So again, best cutting sword possible, probably a backsword (single edged generally straight blade). Katanas, Falchions, and "backswords" fall into this category of sword. I've taken to calling them all backswords, now, because it makes the most sense.

As far as length of the weapon, that depends on the wielder. It's not a "standard" thing. For example, I like the feel of a Wakazashi vs the feel of a Katana simply based on length, because the swords otherwise are the same so for me I'd use say the "ideal" is a short backsword. Others however might prefer a long backsword like the katana or the standard backsword. Still others might prefer a dagger or a much longer sword.

Also after re-reading what you said, if the source of the cutting isn't the sword shape then I'd actually go for a thrusting or chopping based weapon design since the it's already got cutting maxed out. Such as the Rapier or a double edge long sword. I'd go thrust because they look better imo, and they are considered more noble and gallant, but choppers are more menacing. A brute of a villain might use a chopper style.

$\endgroup$
0
$\begingroup$

If it can cut through anything without resistance, the shape would be irrelevant for that. A straight shape would then be the simplest shape. The length is constrained mostly by the user's ability to swing it quickly and most importantly, not hurt himself or his allies.

If the user expects to face similarly equipped opponents, he will opt for a longer sword, as there is very little defense against such a weapon, so hitting the enemy before he can hit you is good.

On the other hand, fighting against opponents wielding normal melee weapons, reach is less important as it becomes effective to chop off their weapons with a quick stroke, neutralizing their advantage. Then speed is king, so a shorter blade.

$\endgroup$
  • $\begingroup$ If speed is king, go for a 1,5 handed blade. While the blade itself moves slower near your hands, the TIP of the blade moves much faster than it could if wielded 1handed. $\endgroup$ – Andreas Heese Sep 14 '16 at 11:56
  • $\begingroup$ Against normal weapons, I'd go for shield and short to average supersword. Block the weapon, cut it off. Step forward, strike, find new opponent. $\endgroup$ – Cyrus Sep 14 '16 at 12:08
  • $\begingroup$ Why not go for super-cutting sword and super-cutting parrying dagger? Blocking and cutting in one move :) $\endgroup$ – Andreas Heese Sep 14 '16 at 12:10
  • $\begingroup$ Parrying doesn't work well with supercutting. You might cut the sword or axe, but that tip or head may still be flying at you. Arrows and spears are much harder to parry as well. $\endgroup$ – Cyrus Sep 14 '16 at 12:18

Not the answer you're looking for? Browse other questions tagged or ask your own question.