Kevlar is a fabric, isn't it?

Currently kevlar can only be repaired with a welder or soldering iron, which means that a small amount of clothing can’t be repaired with sewing equipment (wooden needle, sewing kit, tailoring kit, etc.) even though it really should be.

I’m not sure if kevlar in game is for some reason ‘solid’, but cursory research suggests that most kevlar is woven into a fabric before being used, especially in body armor.

This suggests that you should be able to repair/reinforce clothing made of kevlar with sewing equipment. This is supported by the fact that the player is able to pad out existing garments with kevlar using a tailors kit.

The main reason I discovered this issue was that i found certain pieces of clothing, made only or primarily of kevlar, can’t be padded with extra kevlar to improve their armor rating, which seems unrealistic and inconsistent.

Sorry if this is in the wrong category, I’m currently on mobile and can’t very well tell which is which.

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The idea is that kevlar clothes are made of bonded kevlar and other plastics, and that patching requires fusing kevlar patches into place. I don’t know how accurate this is, if you find any resources, please share them.

Well from what i can tell, it seems kevlar is usually a fabric, then bonded or laminated with more kevlar or other materials. For post apoc survivors that would probably consist of layers of kevlar superglued together.

It’s arguable whether you could sew kevlar armor back together, but the tailors kit already includes a lighter for plastic repairs, so it would make sense to let it repair kevlar.

I do own one Polish military kevlar helmet and one Polish bulletproof vest.

First one is rigid and hard, almost ceramiclike, and what i heard about these helmets is they are made from kevlar patches soaked in synthetic resin.
The vest is made from Cordura (nylon&cotton) and has pouches for 6 kevlar inserts and 2 steel or ceramic plates. Kevlar used there is quite dense, yellow and fabriclike. You can easily see its structure and i think it could be possible to rip it into kevlar threads.

Right – as others have said, “Kevlar” sheets are used to create armor, etc., but making it into armor involves laminating and fusing processes that create a rigid plate or shape. The kevlar layer is on top, and is no longer a fabric that can be sewn or mended.

Maybe the idea of brute-force melting/welding pieces together is why the welder or soldering iron are usable to repair kevlar items.

That does seem to be the method, but raw kevlar could still probably be sewn into whatever lining kevlar plates are held in place with in a garment. Plus, some items are made from pretty much only kevlar, like the RM13 Combat Armor which only has kevlar and ceramic in the material list. We could pretty safely assume that some or all of the kevlar in it is still a non-rigid fabric.

Even then, we still use the tailors kit to attach kevlar to existing items and it says in the description that it has a lighter for fusing plastic, so it should at least be possible to repair kevlar items with it. Let alone attach more kevlar to an existing piece of armor.

From my experience, there isn’t a Kevlar Fabric item in the game. There is only the plating which is usually used as inserts into armour in pockets to protect the area. The tailor’s kit sews kelvar plating into the lining of the object. All you’re doing is making a pocket, putting a kevlar plate in there and then sewing the pocket closed. You’re not creating a new synthweave. The tools to synthweave aren’t present within the game, so any time you’re able to interact with Kevlar, it should be assumed that you’re only interacting with the hard plates. Think of it like a light lump of steel if that helps. You can’t sew that.

You can’t just sew Kevlar in any case. The way the fabric works is in the arrangement of the synth fibers and with tight gripping that can’t really be achieved by hand. If you did it by hand, it would be like sewing with fishing line because your repair isn’t tied in to the central structure of the synthetic weave tightly as it’s made. It’s just a piece of string holding two pieces of kevlar together and would probably burst apart when you put it on. You’re never repairing Kevlar Fabric. You’re repairing the plates. I just assume that the fabric is fine for the wear and tear of apocalypse life and it’s not actually going to get torn or worn out, nor is it able to be salvaged and used again unless the structure is maintained, as in some survivor’s gear needing an actual vest to be crafted.

But hell, I’ve repaired a tank with nothing but an Oxyacetylene torch so this game has much larger internal logic issues than not being able to sew an extremely dense and machine-assisted synthetic fiber weave.

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what you describe in your first paragraph is an armor carrier, not kevlar armor.

You can sew kevlar with a standard thread. But it is slow as hell. You have to open each layer individually and sew each layer together. It would suck ass when there aare 30+ layers and you do each loop one layer at a time…argh…

As a side note kevlar isn’t cut resistant. You can throw a hatchet through it. Youtube guy Wranglerstar actually did this witha piece of crap hatchet he had layin around and a lvl3A vest.

Do it with an AR-500 IV class Rigid armor

As I understand it, it does provide cut and abrasion resistance, but it’s not stab resistant, no.
I’m not a big fan of the current* damage system, I’d like to eventually see cut, pierce, and stab as 3 different damage types with pierce being reserved for bullets, fragments and other very fast, small projectiles. I’d also like to see clothing having discrete protection ratings for them too, but it is what it is for now at least.

(*current as in I don’t think anyone has done a huge amount with it since whales)

It would be nice to see but I’m not sure how easy/time consuming it would be to code, I’m also not sure about reserving pierce just for firearms and such though. If you look at a lot of older armour types they were designed with those three damage types in mind, padding for blunt force, mail for slashing and rigid for piercing/slashing.

This is an example of narrow, piercing weapon used for penetrating chainmail, heavy leather armour and getting through the gaps in plate for instance:

The concept has been around for centuries and weapons of this type were quite common, evolving in regards to changing requirements on the battlefield.

Spears and other similar weapons focused more of a thrusting/piercing type of attack as well and can’t really be classed as the same damage type as an axe or sword designed for cutting.

Technically bullets do bash damage. Like a hammer. But I have no idea how the code works for this game so I don’t know if this was taken into account.

Armor piercing rounds are nothing more than more gun powder to increase the velocity of the projectile.

Fragmentation should also be bash damage. But the explosion is shock damage(pressure, not electric).

Cutting should be reserved for blades. While Kevlar is sturdy. Can protect against bash damage. It sucks hard against a blade. Don’t get me wrong. It would be better than a knife or a hatchet to the chest without the vest. But a sufficient swing from an average strength assailant will penetrate with a blade. Sadly.

Well…sort of. This would make Bleed attacks more of a thing to be certain. But the tricky part is how damagecrosses over.

You can slice with a stiletto. But the deep wounding damage is the primary damage.

You can crush(blunt form damage) break bone with an axe even when you cut. I imagine the coding of all this crap in game gets pretty sticky.

Maybe we need 4 forms of damage with crossovers:

Bash, Cut, Pierce and Pressure.

The current system as I understand it is: there are cut and bash damage types separated by different armor ratings (armor can be better against one or the other). Piercing damage is only relevant with melee weapons, and is differentiated by how critical hits work.

Personally, I think this is fine. We’re mainly interested in how armor reacts, which leads us to how materials react to stress. In this case, we’re mainly interested in how easily a material can be penetrated or cut apart (cutting/piercing) or how well it absorbs and dissipates energy from an impact (bashing attacks). As far as differentiating how piercing and cutting work, I don’t that’s wholly necessary, with the possible exception of an AP bonus to piercing attacks, since trying to cut through a material and trying to poke a hole through a material is relatively similar in the cases we’re looking at (at least as opposed to trying to just bashing the material or trying to burn it away).

The trick here, and this applies to all weapons including guns, is that we need to apply blocked cutting/piercing damage as bashing damage. I.E Get dealt 10 cut damage with 15 cut armor and 5 bash armor, the 10 cut damage is ignored but transferred to bash, the target takes 5 damage.

Once proper wounds are implemented this will help things fall into place, since minor bashing damage will be far less scary than major cutting/piercing damage. With that implemented, everything will be a bit less tanky and things will be far more realistic and satisfying.

Bullets only do bash damage if they aren’t able to penetrate. Under normal circumstances they penetrate the skin and cause hydrostatic shock or whatever and mush up your insides. I suppose that’s kind of like bash damage, but it’s internal and not really what we’re worried about.

That’s not right. Even most small arm AP rounds have some sort of hardened core or penetrator. You’re thinking of overpressure rounds.

True over pressure rounds. But bullets penetrate with velocity then crushing power; “like a hammer”.

edit: oohhh, ok I see what you thought I meant. Heh, you mean you can’t read my mind? lol
But yeah, good catch on that correction. Forgot that bit. Yes indeed a tungsten or lead core helps provide weight needed to penetrate.

Sorry for the impending wall of text, but I do a bit of game design myself and I feel a little strongly on this topic in the context of game mechanics and finding a suitable degree of representation and abstraction, since it’s quite applicable to my own game. Not all of this is applicable to CDDA specifically, but I enjoy thinking about and discussing it as discourse.

I know that yes a bullet is literally “crushing” the tissue to form a cavity, but the wound it causes is very different from any form of wound that could be caused by a hammer or similar blunt object, and - in any sort of game design with in-depth damage mechanics - you’ll almost never find it represented as a “bashing” attack.

For game mechanics, I always interpret it in terms of the sorts of wounds weapons and projectiles cause in soft tissue specifically. A cut (such as a laceration or incision) is very different to a contusion (caused by blunt force trauma) which is again very different to a puncture wound (being stabbed or impaled) which is again very different to a gunshot wound. The four types of soft tissue wounds I’ve listed here would cover all the basic forms of damage in game with different forms of protection being better at protecting from some of these than others. I find that these four basic types provide the best mix of abstraction and accurate gameplay mechanical flexibility.

On the topic of “pierce” being exclusive to firearms, I’m just using that word as a label to generically ascribe the type of wounds you see in gunshots - it would also extend to other small, high velocity objects that might literally be crushing tissue to cause wounds (e.g. high velocity fragments from explosions and potentially exotic attacks from creatures) but behaves very differently to blunt force trauma which is what bashing damage is meant to represent. Honestly, I picked that label since it’s used in GURPS which is a very good system for universally representing the different types of wounds someone could suffer. A stiletto striking the body (and intervening material) produces effects comparable to a spear or arrow strike, and not comparable at all to a gunshot wound. To portray what you’ve mentioned in gameplay terms, if a melee weapon could be given an AP value, the stiletto would have a higher one than a spear, but would ultimately be causing a smaller and cleaner wound than a spear.

Classically, yes, there’s the three types of physical damage and armour you see in a lot of games, but this model isn’t as applicable when you begin to incorporate firearms into the picture. The whole idea that sparked this part of the thread is from @TheZoneWizard’s comment that kevlar isn’t like chainmail or a steel plate (as quoted it “isn’t cut resistant”), hence the need for at least one more basic damage type to represent this.

Indeed, collectively the types of damage caused by an explosion are called blast injuries. In academia and medicine, you’ll often find them breaking it down into specific wounds which usually include fragmentation wounds (which you’ve already covered), flash burns, and blunt trauma from the overpressure. But this is quite unique and differs from other blunt trauma in that it does extensive damage to internal organs and causes amputations and other such injuries that we don’t associate with typical blunt trauma. I think damage from just overpressure could be, for gameplay purposes, adequately and simply represented with large amounts of bashing damage tbh, particularly to the torso. You could also add another damage type specific to overpressure - there are already many special types of damage in the game such as poison, fire, cold, radiation etc - but sometimes it’s sufficient to use the more basic mechanics than develop new special rules. And with that statement, I’m led to my next part of the post…

Absolutely, to bring it all back around to CDDA, while playing I don’t really think of these things and I still enjoy the game with its current level of abstraction. I haven’t actually looked at the projects open on github for a long while, but with the way the game has been going, I don’t have any doubt that Kevin et al would ultimately want to expand on the wounding system and have specific treatments using up different resources for different types of wounds (so players stop applying disinfectant to a perfectly sterile bruise). I’m hopeful that the basic damage system will be refreshed in the process too. In the meantime I’m happy enough fooling around in the cataclysm as is.

Cheers!


PS: don’t want to be too pedantic with this, but the tungsten and steel penetrators aren’t meant to provide “weight”, they provide strength and rigidity to the projectile so it won’t deform or destabilize as much as a simple copper-jacketed lead projectile.

I see your point and agree, I guess I was just getting a bit too tied up with labels :stuck_out_tongue:
It might be a nice addition tbh if melee weapons did get a AP value beyond just damage level or damage type, the stiletto I gave as an example above for instance wouldn’t really do all that much damage (comparatively speaking) compared to a well made spear but should be better at dealing damage vs armoured targets. There are other examples but I think part of the problem with recoding the damage mechanic (beyond the actual coding involved) would be the sheer amount of work that would have to go into rebalanicing everything involved.

I didn’t really feel it was needed to be so exacting as I am confident most people can google everything you wrote. But I am also aware of those point all the same.

Though the hammer bullet thing is accurate. If I could smack an object fast enough with a hammer. The damage would be similar to a bulletof equal size to the hammer as with a bullet.

You can see this in action iinvideos for example sake when people shoot solid objects and they show the audience the bullet. If assuming it didn’t fragment instantly, you will see it has that hammer effect. It is a blunt object pushing so hard it flattens out or starbursts. Shotgun slugs are a good example. They just bash through the target object.

Kevlar is a good example of the hammer effect. Kevlar catches the bullet because of the hammer effect. Where as a cutting edge goes straight through it.


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Umm…well yes. Heavier the projectile. The projectile should impact with a greater force. Soooo…ok. Think as you please.

edit:excuse the typos. Stuck using a 7" tiny ass keyboard.

You’re confused. Most bullets flatten out because they deform because they’re made of a soft metal (lead). This deformation expands the area affected by the bullet, making it more like a hammer blow in that it spreads the energy over a larger area. This is nice because if a bullet acted like a needle it would do very little damage and just pass straight through a person. Bullets tend to work like needles until they go into a person, then flatten out into a hammer and unload all their energy into the target.

While tungsten is heavier than lead, steel isn’t, and the weight of the projectile isn’t the important part in AP rounds. Whether the projectile is light and fast or heavy and slow, the energy transferred (and the force applied) is roughly the same, so the damage done by, or armor required to, stop the projectile is roughly the same. The issue is that most lead bullets shatter and deform on hitting a harder target, which is often a good thing, and means they do far more damage to targets they penetrate. Steel/tungsten penetrators and even the copper casing on FMJ rounds harden the projectile doing the energy transfer, allowing it to penetrate without losing shape. You could say you’re focusing the energy on getting through the material rather than applying it to the material. However, that also means they tend to go straight through soft targets without causing any real damage, at least compared to a hollowpoint round.

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