Someone in the SCA in Southern California made a helmet out of titanium (he worked in a machine shop, and saved up scraps until he had enough). It was way too light; the first time he got hit, the force of the blow just about broke his neck. Part of the protectiveness of armor is sheer mass to absorb the force of the blow.
Some armorers are using titanium to reinforce armor (a strip running along the center line of a helmet (where a mohawk grows) strenghtens it considerably. The problem with titanium is that it can be very brittle unless cold-treated.
I have made mail using 1/4" stainless spring steel lock washers; a machinist tested a swatch and said that it was as strong as 14 gauge steel, which would stop arrows. Wouldn’t help much against a mace, though.
My question is: by the late Middle Ages, european armor was beautifully developed, and very well made. I have seen some examples of Italian-made armor, in which the elbow and knee joints worked very smooothly. Howeer-was most of this stuff ever actually used in battle? Most of the armor you see is undented and quite pristine-my guess is by the 13th century, armor had become a ceremonial thing, mostly just used for parades and posturing (likemour militarie’s dress uniforms-nobody would actually expect a US marine to go into battle wearing his dress uniform!).
Any comments?
Armor was worn regularly up to the late 16th century, when a bunch of spoilsports developed cannon, guns, the Welsh longbow, and other things which could punch through any armor currently available, so they stopped wearing it.
The people who commissioned the great-looking stuff usually had several sets of armor; the stuff that survived never got worn. Also, they grew out of it if they had armor as teenagers.
There’s a site, http://odur.let.rug.nl/graz/graz.UK.html, which has pictures of the arsenal at Graz, which was where a lot of the armor of the time was made. There was a war which almost made it to Graz, then ended. Most of the people for whom the armor had been ordered were dead, or no longer interested in wearing armor, so it all just got warehoused for a few hundred years.
On the mace/puck hijack: Don’t forget the impact area. The flanges on a mace are narrow and rather pointy; properly swung, the impact zone should rarely be more than .0625 in[sup]2[/sup] (1/4 inch * 1/4 inch). I’m not sure of the dimensions of a hockey puck, but it’s surely at least half an inch thick–you can probably SWAG a typical impact zone of at least .25 in[sup]2[/sup], assuming an edge-on impact. A flat impact would, of course, spread the energy over a much larger area than that. So, and edge-on impact would spread the energy over roughly 4 times as much area. Puck details from the hockey players would be welcome.
On the anti-bear armor: The nutcase actually wears the suit in most of the tests. I’ve seen footage of him being hit by a truck and a tree trunk. The front of the truck was padded; the tree wasn’t. The chestpiece of his armor is reinforced with a titanium plate, and it uses inflatable internal padding. He won the 1998 IgNobel Prize for Safety Engineering for it. I think that he was one of the presenters in 1999.
I used to broadsword fence with a buncha SoCal buddies in the early '90s. Most medieval types would have had to think for a few minutes to recognize our armor as armor: Kevlar and high-density closed-cell foam, PVC and nylon, and a few other, less explicable elements. Shields made from 3/4" marine plywood and boiled bullhide would’ve been the most familiar. One lesson learned early on is don’t make your shield light: You’ll wind-up eating it with the first body slam. Swords only: Warhammers, maces, and flails all ruled too dangerous. My foil (broadsword, I still have it) weighs 4 & 3/4#. Solid, heavy armor is a plus, up to a point. Our stuff had good flexibilty/mobility, too.
One point: Even with good armor, you can still be badly injured. I tore my left quads clean through on a bungled lunge.
.
A gambeson works wonders, especially if made of good modern materials. I wouldn’t want to test it against a mace though. Also: Spring washers are split, and a spike-headed arrow could easily force through the rings by spreading them rather than breaking them.
Turkish chainmail was made without the welds used elsewhere (similar to your washer-mail), and the resulting weakness spawned a ring-splitting dagger. It had a needle point for getting into the ring, a single cutting edge, and the spine of the dagger was ‘T’ shaped for strength and leverage. The idea was to stab past the plate armor into an area protected by only mail, where the long, thin dagger would split the rings and puncture vital organs. I think, perhaps, your washer-mail would resist this rather better than the original stuff would’ve.
Actually, if a puck rebounds, that makes its change in momentum larger, not smaller. The impulse (force times time interval, and equal to change in momentum) is thus also larger. An object that strikes you and rebounds (such as a rubber bullet) may do more injury than one that comes to a halt (though those pesky bullet holes can cause problems…)
Energy deposition per unit time is the issue with the bullets: A bullet that stops has deposited all of it’s energy into the target, and recieved none back: Non-elastic collision. A rebounding object recovers some of the energy from the target or stores energey in the form of elastic deformation/other internal mechanisms. This recovered/stored energy has no additional effect on the target. By definition, a projectile can only deposit as much energy as it’s total energy. The faster the pojectile stops, the more energy deposited per unit time, the more damage done to the target. This is why bullets are designed to mushroom: To stop them faster (this, of course, neglects wound ballistics: A whole 'nother thread). Thus, re-bounding bullets can’t do more damage than those which stop. Dosn’t mean the bouncers don’t hurt like hell, though.
[/Hijack]
I don’t have a mace, but I do have a run of the mill hammer. I’m pretty sure that getting hit in the head by a hockey puck would hurt a lot, probably cause a concussion, and possibly but not likely kill me. I’m also sure that if a big strong man hit me in the head with a hammer it would definitely fracture my skull, and probably kill me. Based on this, I’d have to say that a mace and a hockey puck aren’t even in the same ballpark (or rink) when it comes to how much damage they could do to the human body.
Additionally, maces were designed to hurt people. Hockey pucks weren’t.
Sure, we could make full plate lighter nowadays, but I doubt that that would make much difference to the comfort level. I once made a suit of fullplate “armor” out of posterboard for a Halloween costume, and I still had almost zero mobility.
Roman banded mail (the lorica segmentatae, on the other hand, barely seems to restrict movement at all.
It can. To make it more clear how the recovered energy can do more damage, imagine someone wearing armor only on their front, and is hit in the back. The bullet goes through the body, makes a messy hole, hits the armor in the front, rebounds through the body again, creating another messy hole. This isn’t a hypothetical situation; it has happened. The effect isn’t as dramatic if the energy is recovered at the surface, but that doesn’t mean it doesn’t occur.
It’s not that simple.
Yes, it does ignore wound ballistics. Mushrooming is done
for reasons completely separate from increasing the energy/time ratio per se. One reason is to make sure it expends all of energy and doesn’t just shoot out the other side of the person, and increasing the energy/time ratio is a means to achieve this, but is not an end in and of itself.
Rather quick on those generalizations, aren’t you? If you’re after blunt trauma, rubber is much better than, say, clay.
If one counts wound ballistics, yep. I did, however (I think) make it clear I was deliberately ignoring wound ballistics (which are a function of energy conversion & projectile behavior, and need a thread of their own). What you’ve just described is a through-and-through wound (failure to completly deposit all energy), followed by another entry wound (BTW, hocky pucks and rubber bullets are rather unlikely to do this). In this scenario, all energy originally posesd by our projectile, less the energy lost in the rebound, are deposited in the target.
Yup, and I was offering a generalization, as I didn’t want to hijack this thread too far. Oh well.
Wound ballistics are a funtion of energy conversion within a particular organism. Projectile behavior within the organism (victim), and is carefully considered when designing bullets. Again, the subject for a schollarly tome or twenty.
Yup. Sure am.
Again, by definition, a projectile can’t convert any more energy than it poseses in the first place. If a projectile has sufficent energy to rebound, then all of it’s energy wasn’t expended on the target. I had, of course, deliberately ignored wound ballistics, as being too large a hijack, and I’d not planned on going into freakish circumstances as being struck twice by the same projectile.
So, to recap: Hocky pucks are going to do less damage (on average) than a well-swung mace.
If the bullet comes to a stop, then all of its energy and momentum are transferred to the target.
If the bullet rebounds, then its new velocity and momentum vectors now have negative values (direction has reversed). In order to balance the equations, the target now has velocity and momentum vectors greater than they would have been if the bullet had stopped. So, a rebounding projectile can easily do more damage that one that sticks. This is the principle on which harpoons work.
As always, the real world is not this simple. The duration of the impact and the surface area of the impact are also important, as well as the type of tissue being impacted.
Ethilrist- While I like the idea, it sounds like the Chain would be rather heavy… which is the risk one takes when wearing Mail on the field, but still…
Also, the idea of chainmail stopping arrows is faulty… Arrows would hit, and while the first few might get stopped, they would split links, which would then fall off and weaken the entire weave. Eventually a hole would appear, if someone didn’t nail you with a self-bow that would just punch through… very painful, ask he footsoldiers ar Crecy`.
There are hundreds of armorers that make their stuff today with the best steel around, with modern techniques and tools… and it’s still not that much better than what was turned out at the High point of armoring (mid-late 1400’s, just before gunpowder and what-not became more common).
It would be completely possible to make something out of modern materials (kevlar, ceramic plates, etc.) that would work for modern combat… walk into the crack house, swinging a sword and hacking the badguys as bullets blast at our hero, without punching through. But pure Kinetics would knock our hero down, and eventually someone would get him.
Now, I’m about to embark on learning to make my own armor… I’ll get back to you on it when I’ve shot my helm with a .38.
Problem is, where does the energy come from that reverses the vector? Now I’ll submit that if the target is motionless at the time of the strike, then the energy must either come from:
energy stored within the projectile itself (usually in the form of compression {we’re talking about hocky pucks and rubber bullets, mind}) deformation or reflected shock-waves.
energy stored within the target itself (again, in deformation, compression, and in the case of living bodies, to some degree, reflected shock waves.)
Conservation of energy isn’t just a good idea, it’s the law.
Now, if the target is moving in relation to the projectile, that complicates things a bit: The collision energy will be the vector sums of each body’s energy. Never-the-less, total energy must stay constant within the equation. Now, on reflection, it is possible for a projectile to tranfser all of it’s energy to a target, only to recieve some of that energy back and be impulsed away from the point of collision. Still, the only energy transfered to the target can be no more than the energy inherent in the original vector sum. So, unless your point is that the act of transferring energy from the target back to the projectile is injurious (remember: This process starts with the bodies in intimate contact: There is no Delta-V between the target and the projectile), then I’ll stick to my point. If your point is that this is injurious, I’ll ask for more than vector equations. I’ll want to see the biomechanics.
Again, we’re talking about non-penetrating collisions. When we’re talking about bodily penetraton, biology gets seriously involved, and things get messy and really difficult to sort out.
I don’t know too much about harpoons. Mebbe you could run a thread on that subject? Do they create the same kinds of wound ballistics as smaller projectiles do? I thought they worked on a combilation of massive wounding and a bursting charge?
