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Feddlefew
2013-08-01, 10:47 PM
I'm trying to design a fishing spear (for fluff reasons) that will also make a decent weapon. Most of the trouble I'm having is with picking out materials.

It needs to have the following attributes:
-Throwable.
-Very corrosion resistant, because it's meant for saltwater fishing.
-A flat spearhead with several teeth cut into one side of the blade. Needs to be able to penetrate boney armor.
-A chain, cable, or rope that attaches via cuff to one of the user's wrists, so that the catch can be pulled in. Needs to be very strong.

Edit: After doing more research on fishing spears, I think what I want is a basically small harpoon.


The tech level is schizo, so while the knowlage of how to make modern (and space age) materials exists, the facilities don't. The neglectful precursors of the backstory used a lot of bioengineering, but that's a little beyond the reach of my character right now.

JusticeZero
2013-08-01, 11:00 PM
Steel. just take care of it a bit. Use oil on it as needed. Steel is still an awesome material, and regularly the best material around even in super high tech settings. So is a hardwood shaft, or a good fiber rope.

Dundee15
2013-08-02, 12:30 AM
A fishing spear and a combat spear are quite different. A fishing spear usually has barbs on it to pull the target (usually a fish) back to the wielder. A combat spear doesn't have the barbs as you wouldn't want your weapon to get caught inside a target leaving you unarmed and unable to defend yourself... unless that's part of the plan. You could throw it into an enemy and pull them back towards you but that would still leave you spear-less.

Feddlefew
2013-08-02, 01:06 AM
A fishing spear and a combat spear are quite different. A fishing spear usually has barbs on it to pull the target (usually a fish) back to the wielder. A combat spear doesn't have the barbs as you wouldn't want your weapon to get caught inside a target leaving you unarmed and unable to defend yourself... unless that's part of the plan. You could throw it into an enemy and pull them back towards you but that would still leave you spear-less.

My character is in a situation where they only have what was with them at the time of their abduction, and they were in the middle of drunken spear fishing. Since it's supposed to be use for catching large aquatic animals(like giant turtles and sea serpents) by an amphibious species, it's meant to get stuck in the prey and allow a group of hunters to restrain and kill it.

I also plan on picking up a knife ASAP.

Lorsa
2013-08-02, 05:23 AM
So do you want help with coming up with ideas (or pictures) on how this spear (harpoon) is supposed to look and what it is made of or do you need help with ideas for how your character might build this weapon in the game using some raw materials we don't know of?

Ideally you want the spearhead and the teeth to be made of diamond and the rope/chain of carbon (which is what diamond is made of too). Not sure what the actual spear should be made of but to be throwable it needs to be lightweight but heavy enough not to get blown away by wind. Titanium maybe? Not sure what is best. Perhaps it could be made of carbon too. This is all assuming the world can manufacture diamond and don't need to dig it up from the ground.

Xuc Xac
2013-08-02, 10:05 AM
A diamond spearhead on a titanium shaft is probably the worst possible combination. Diamond is the last thing you want on an impact point. It's really hard, but that means it's also really brittle. Hardness and shatter-resistance are generally mutually exclusive. When making weapons, you have to find a happy medium between "hard enough to hold a sharp edge" and "soft enough to avoid shattering when you hit something". Diamond is too far on the hard end of that spectrum. And titanium is not a super metal. It's really strong for its weight but it's not very dense so you need a lot of it to match steel. If anything, it's a superior version of aluminum (but not superior enough to use for any martial applications).

The best materials for making melee weapons are still what we came up with in the Middle Ages: solid wood and good quality steel. With all of our modern materials science, we still haven't come up with anything better although we can produce that good steel more quickly, more reliably, and in larger quantities. The important thing to understand about materials science is that materials don't "level up". They're tools and they are suited for different jobs. Much like a Phillips head screwdriver is a more advanced technology than a hammer, but it can't replace a hammer.

I think you might be able to replace the wooden shaft of a melee spear with some kind of high-tech carbon fiber/graphite composite, which would make it lighter and allow you to move the business end faster for swifter impacts. But I don't think you would want to make a harpoon lighter because that would cut down its impact when it strikes because you can't follow through with your weight when the weapon is out of your hand. A harpoon doesn't need a flexible shaft but it needs some weight for extra momentum, so you'd want a shaft of some hardwood (probably something cheap and easy to replace because they tend to get broken a lot when thrust into a huge beast that then thrashes about).

TheStranger
2013-08-02, 10:24 AM
I'm not sure why you would want diamond. It's very brittle; not at all suitable for weapons. The same goes for most ceramics; whatever you gain from the hardness/sharpness of the blade, you lose in durability.

The poster who suggested steel was absolutely right. And you really aren't going to do much better than wood for the shaft, although you could conceivably go with some type of fiberglass or carbon fiber material if you really want to. But wood and steel has worked just fine for a whole lot of years, and it's easy to make without advanced tech. It'll bounce off rocks, shells, and bone without major damage, which is one of the biggest things you're looking for in a fishing spear. Take care of it, and the saltwater isn't really an issue.

As for the rope, I'd suggest something along the lines of parachute cord. That's about as lightweight and strong as you're likely to get. But you don't really need a superstrong material unless you can anchor it to something solid. Otherwise, anything that could break the rope isn't something you want to play tug-of-war with. You'd just end up cutting the rope before you got pulled under anyway.

The Fury
2013-08-02, 12:13 PM
While steel is pretty durable I'm sort of surprised that nobody's mentioned bronze. Bronze has some obvious shortcomings when compared to steel, it's heavier and softer than steel. That said, it does have some properties that might make it pretty good as a fishing spear. For one bronze would not corrode from being immersed in salt water, for another it actually holds an edge fairly well. If the spear was designed to have easily replaceable heads then the fact that you're using a softer metal might be less of an issue.

Another metal which might be good to use is wrought iron. While wrought iron does corrode, it won't corrode as much as cast iron or carbon steel.

Lord Torath
2013-08-02, 12:55 PM
Another great material is wrought iron. It will hold your edge better than bronze, and also won't corrode. (The Eiffel Tower is made of wrought iron, and has no protective coating)

Edit: Nevermind. Bronze is better (http://www.anvilfire.com/21centbs/armor/atli/index.htm) when it comes to holding an edge.

JusticeZero
2013-08-02, 02:44 PM
Sure, but there's a reason why bronze weapons were abandoned by pretty much every culture that figured out how to make steel. It's just a superior material to make a blade or tool with. And it doesn't corrode in seawater unless you're leaving the darned thing in the salt water in between fishing seasons. Minor care will keep it looking good as new for a long time.

Knaight
2013-08-02, 03:13 PM
Sure, but there's a reason why bronze weapons were abandoned by pretty much every culture that figured out how to make steel. It's just a superior material to make a blade or tool with. And it doesn't corrode in seawater unless you're leaving the darned thing in the salt water in between fishing seasons. Minor care will keep it looking good as new for a long time.

They weren't abandoned entirely until even steel weapons (that aren't guns) were almost abandoned. Bronze is a really, really nice material for weapons that don't need the edge, flexibility, and similar things of steel, which basically meant it stuck around for maces, hammers, etc.

JusticeZero
2013-08-02, 04:00 PM
Yes, but "edge, flexibility" are two properties that the spear described needs to have.

Knaight
2013-08-02, 04:13 PM
Yes, but "edge, flexibility" are two properties that the spear described needs to have.

And bronze was dropped for spear heads when steel was available for very good reasons - I was just making small corrections to a slightly overly broad statement.

Gavinfoxx
2013-08-02, 06:26 PM
You'll have to use a really exotic type of bronze to get even close to steel, but high tech cultures, um, can make really exotic types of bronze!

http://en.wikipedia.org/wiki/Phosphor_bronze

Just say it is a really advanced bronze with around four of these things alloyed into the copper in really precise amounts:

Tin
Arsenic
Zinc
Phosphorus
Aluminum
Silicon
Manganese
Lead

Xuc Xac
2013-08-03, 01:19 AM
Bronze wasn't abandoned because steel was better. It's because iron was cheaper. Bronze is an alloy. When the tin trade was disrupted, bronze became expensive so people who couldn't afford bronze switched to inferior but cheaper iron. For a time, officers carried bronze swords while the rank and file soldiers used iron. Eventually, iron-working technology advanced to the point that they could reliably produce good steel that was better than bronze, so they didn't go back to bronze when the tin became cheap again.

If you're making weapons, the hierarchy of metal quality is something like this:
copper<iron<bad steel<bronze<good steel

Making the transition from iron to good steel is much harder than making the jump from copper to bronze. Working with bronze is much, much easier than working with steel. Bronze requires less infrastructure to refine the metal and much less effort to work it into a usable item. Bronze can be melted and poured into a mold but iron has to be heated and beaten for a long time.

Gavinfoxx
2013-08-03, 11:53 AM
And for things that can't be painted and which will be in saltwater a lot (like ship propeller screws), the modern bronzes with all of the alloyed other materials are absolutely fantastic.

The Fury
2013-08-03, 01:30 PM
And for things that can't be painted and which will be in saltwater a lot (like ship propeller screws), the modern bronzes with all of the alloyed other materials are absolutely fantastic.

Yep. And according to Feedlefew the people using these spears are amphibious and fish in salt water, so they would probably be immersed in seawater almost constantly. I'm sticking with bronze or wrought iron as my preferred materials. Though I hadn't thought of modern bronzes for some reason. Nice one, Gav!

Knaight
2013-08-03, 02:30 PM
Yep. And according to Feedlefew the people using these spears are amphibious and fish in salt water, so they would probably be immersed in seawater almost constantly. I'm sticking with bronze or wrought iron as my preferred materials. Though I hadn't thought of modern bronzes for some reason. Nice one, Gav!

They would be immersed in salt water briefly, when used in fishing, but probably kept at hand above water most times, and usually dry. A propeller for a ship, meanwhile, will literally be in the water 24-7. Steel is just as good in this case.

Feddlefew
2013-08-03, 03:34 PM
To answer some of the questions about the setting:
-Her species spends most of their time above water, and store there equipment above water. However, they do fish underwater, which would mean several hours of exposure.
-They use geothermal power to generate electricity.
-They have access to a few functioning computers, but they don't have the facilities necessary to build their own.
+Computers are large enough that they cannot be moved without taking them apart and rebuilding them elsewhere.
+They could reprogram a computer to help with metallurgy... but if it needed specialized sensors, they wouldn't be able to make them.

As for the good steel/bronze argument... I'd need to know what goes into making "good steel" to judge. From what I know, making steel involves removing the carbon from pig iron, and then adding it back in to make a specific carbon to iron ratio.

Gavinfoxx
2013-08-03, 05:19 PM
One of the things about making steel is that it requires really good, hot furnaces of various sorts. If you have a super hot furnace, you can figure out what to put in it relatively easy...

endoperez
2013-08-03, 06:46 PM
Assuming they have a supply of bronze of the correct composition, wouldn't it be relatively simple to melt down and re-cast the bronze, allowing for near-perfect recycling of a material they can't create? A lost bronze spear would be a permanent loss of the raw material, recovering it would be a priority and finding a few kilos of the raw, unused material (e.g. parts of a specific machinery) would benefit the finders for generations.

Also, instead of wood there could be some other biological material with similar characteristics but less bendyness, more water resistance. Perhaps something like the suggested carbon nanotubes are the bones of an artificial monster?

TheStranger
2013-08-03, 07:17 PM
One of the things about making steel is that it requires really good, hot furnaces of various sorts. If you have a super hot furnace, you can figure out what to put in it relatively easy...

Modern steelmaking, yes. But people have been making steel for several thousand years (including wootz steel, which we can't figure out how to make today). Tech level isn't a barrier to making steel. (Not to say you don't need a good furnace, just that a good furnace isn't hard to get)

I'd say steel vs. modern bronze is largely a matter of taste. Personally, I prefer steel, because I think it makes a better weapon and corrosion isn't a big issue, but I'll admit that a good bronze will make a functional, corrosion-resistant spearhead.

warty goblin
2013-08-03, 07:46 PM
Assuming they have a supply of bronze of the correct composition, wouldn't it be relatively simple to melt down and re-cast the bronze, allowing for near-perfect recycling of a material they can't create? A lost bronze spear would be a permanent loss of the raw material, recovering it would be a priority and finding a few kilos of the raw, unused material (e.g. parts of a specific machinery) would benefit the finders for generations.


I talked with a bronze caster recently. Apparently some parts of the alloy burn off when it is melted, so that although scrap bronze can be remelted, you want to add fresh to the crucible each time. Otherwise your alloy changes with repeated meltings into something less desirable.

Also any edged tool will require sharpening, which removes material that is difficult to impossible to recover.

Finally, bronze is relatively easy to create, so long as the ores are available. It has a lower melting point than copper, and is far easier to cast. But a couple kilos isn't very much of the stuff, bronze is as a rule denser than ferrous alloys.


I'd actually figure you could make a good fishing spear out of wood set with stone barbs. Which was probably how most such implements were fashioned during the bronze age, since the stuff was so monstrously expensive. The barbs would break every now and again, but if you had reasonable access to flint, replacing them would be the work of an afternoon or so.

paddyfool
2013-08-03, 08:30 PM
And for things that can't be painted and which will be in saltwater a lot (like ship propeller screws), the modern bronzes with all of the alloyed other materials are absolutely fantastic.

If modern materials exist in this setting, but the facilities to manufacture them don't... what if the harpoon head was recast from one of the blades of a fancy bronze propeller screw salvaged from a wreck? (Salvage should be a pretty feasible exercise for an amphibious species).

neonchameleon
2013-08-03, 08:46 PM
Sure, but there's a reason why bronze weapons were abandoned by pretty much every culture that figured out how to make steel.

The main one: The earth's crust is 32% iron (it's the most stable element in the universe). Bronze = Copper + Tin. Both rare.

Feddlefew
2013-08-03, 09:25 PM
I think using a Puddling Furnace (https://en.wikipedia.org/wiki/Puddling_%28metallurgy%29) might make steel making possible at their tech level. However, I'm worried that, without access to chromium, steel might corrode too quickly to be useful.

Coidzor
2013-08-04, 12:05 AM
My character is in a situation where they only have what was with them at the time of their abduction, and they were in the middle of drunken spear fishing. Since it's supposed to be use for catching large aquatic animals(like giant turtles and sea serpents) by an amphibious species, it's meant to get stuck in the prey and allow a group of hunters to restrain and kill it.

I also plan on picking up a knife ASAP.

...Your character wouldn't have a knife on them while they're out spearfishing?

They should already be dead ages ago if that's the case.

Feddlefew
2013-08-04, 12:20 AM
...Your character wouldn't have a knife on them while they're out spearfishing?

They should already be dead ages ago if that's the case.

They may or may not have had the knife with them. I'm still trying to decide if they lost it some time between getting drunk and waking up on a spaceship, or if they were too drunk to have brought one with them.

The rule was we could only pick one weapon to have with us, so I picked the one that was thematically appropriate and would be harder to make or find.

warty goblin
2013-08-04, 12:22 AM
...Your character wouldn't have a knife on them while they're out spearfishing?

They should already be dead ages ago if that's the case.

I don't even leave my apartment without at least a pocketknife. When I went home for a week, I had (counts)... six knives of various sorts. Damn things are just too handy not to have.

Coidzor
2013-08-04, 12:34 AM
They may or may not have had the knife with them. I'm still trying to decide if they lost it some time between getting drunk and waking up on a spaceship, or if they were too drunk to have brought one with them.

The rule was we could only pick one weapon to have with us, so I picked the one that was thematically appropriate and would be harder to make or find.

They're a hunter-gatherer. Emphasis on the hunter. They have a knife on them pretty much 24/7, what that knife actually is depends upon the tech level and culture. Anything from a flint knife for a neolithic individual to a Sami Knife (https://en.wikipedia.org/wiki/Sami_knife)/Machete or puukko (https://en.wikipedia.org/wiki/Puukko)/belt knife. If they get drunk enough to lose their knife... see aforementioned having died ages ago with that kind of bad habit and carelessness as a hunter-gatherer.

Feddlefew
2013-08-04, 01:14 AM
They're a hunter-gatherer. Emphasis on the hunter. They have a knife on them pretty much 24/7, what that knife actually is depends upon the tech level and culture. Anything from a flint knife for a neolithic individual to a Sami Knife (https://en.wikipedia.org/wiki/Sami_knife)/Machete or puukko (https://en.wikipedia.org/wiki/Puukko)/belt knife. If they get drunk enough to lose their knife... see aforementioned having died ages ago with that kind of bad habit and carelessness as a hunter-gatherer.

She's more of a jeweler in a society that expects everyone to be able to participate in sea monster hunt as a right of passage- in fact, her only other possession right now is her journeyman piece*. My original plan was to bring her kit of jeweler's tools, but the game master decided that it was OP, considering the amount of mischief she could get up to with it on an allegedly abandoned ship.

Depending on what the game master's finalized backstory is, the knife may be
-Confiscated, if this is a death match.
-In the possession of the character armed with only a knife.
-In storage where she can't get to it- the two items she has with her may be considered culturally unique** and thus were being studied when the ship was abandoned.
-Currently lodged in something.

* Her other top priorities are getting foot wraps and a bag to carry things in.
**Fishing spears are not unique. The way this one is built and meant to be used is.

paddyfool
2013-08-04, 03:35 AM
A note on that salvaged propeller screw idea: does anyone have any idea how hard it might be to recast or reforge a modern bronze alloy?

Gavinfoxx
2013-08-04, 02:34 PM
A note on that salvaged propeller screw idea: does anyone have any idea how hard it might be to recast or reforge a modern bronze alloy?

I'd suggest you wouldn't recast it, and would instead cut and grind it?

warty goblin
2013-08-04, 02:46 PM
I'd suggest you wouldn't recast it, and would instead cut and grind it?

With what? Unless you have angle grinders and belt sanders lying around, cutting metal is very difficult, and grinding extremely time consuming. It also wastes a lot of material. Melting down and recasting is a lot easier than grinding something out of a big chunk of raw material.

The good news in terms of taking something large like a ship's propeller and reducing to pieces of usable size is that bronze becomes brittle when heated. So toss it on a really big fire until it glows like a cherry, then smack it with a sledge hammer a bit until you've beaten off some pieces you can melt down.

JusticeZero
2013-08-04, 06:57 PM
If I recall, a major advantage of bronze is that you can recycle it by melting it and pouring it into the new mold. Steel required more tinkering.

Feddlefew
2013-08-04, 07:04 PM
If I recall, a major advantage of bronze is that you can recycle it by melting it and pouring it into the new mold. Steel required more tinkering.

Is this because steel will absorb carbon from its surroundings during heating, or...?

warty goblin
2013-08-04, 07:14 PM
Is this because steel will absorb carbon from its surroundings during heating, or...?

Iron and steel melt at much higher temperatures than bronze. They absolutely can be cast, lots of modern things are made from doing this, but it's a pretty tricky feat to pull off with charcoal. Wootz (Damascus*) steel is a crucible steel, which means that the iron ore is fully melted during the smelting process, but to the best of my knowledge this was just done to produce an ingot, not a finished product. The Chinese apparently could produce cast iron finished goods, but cast iron would make a crappy material for weapons.

Unless you can readily make fires capable of holding over 2000 degrees, and have some way of manipulating a mold at nearly those temperatures, your ironmongery is limited to hammer-work.


*One of the most abused terms. Depending on who you ask, Damascus steel is any steel with a wavy sort of pattern, a Wootz steel with a wavy pattern due to trace impurities of vanadium forming crystals in the surface of the steel, or sometimes even specifically pattern welded steel. The later really pisses me off, because pattern welding is entirely distinct as a process.

Feddlefew
2013-08-04, 07:33 PM
Iron and steel melt at much higher temperatures than bronze. They absolutely can be cast, lots of modern things are made from doing this, but it's a pretty tricky feat to pull off with charcoal. Wootz (Damascus*) steel is a crucible steel, which means that the iron ore is fully melted during the smelting process, but to the best of my knowledge this was just done to produce an ingot, not a finished product. The Chinese apparently could produce cast iron finished goods, but cast iron would make a crappy material for weapons.

Unless you can readily make fires capable of holding over 2000 degrees, and have some way of manipulating a mold at nearly those temperatures, your ironmongery is limited to hammer-work.


*One of the most abused terms. Depending on who you ask, Damascus steel is any steel with a wavy sort of pattern, a Wootz steel with a wavy pattern due to trace impurities of vanadium forming crystals in the surface of the steel, or sometimes even specifically pattern welded steel. The later really pisses me off, because pattern welding is entirely distinct as a process.


So, is that 2000 degrees F or C? I'm assuming the former, because that's just a bit (relatively speaking) lower than the temperature needed to melt glass. Am I correct in thinking that a glass furnace is similar to what they would need to make steel? Because it's not that hard to make a coal or charcoal fueled glass furnace. It's not like they'd be needing industrial sized amounts, anyway.

warty goblin
2013-08-04, 07:48 PM
So, is that 2000 degrees F or C? I'm assuming the former, because that's just a bit (relatively speaking) lower than the temperature needed to melt glass. Am I correct in thinking that a glass furnace is similar to what they would need to make steel? Because it's not that hard to make a coal or charcoal fueled glass furnace. It's not like they'd be needing industrial sized amounts, anyway.

I had my number wrong. Iron melts at 2800 F. I'd guess (and recalling a conversation I've had with a guy who does iron pours) that you'd want your furnace a bit over that, like around 3000 F. It also needs to hold that temp for a reasonably long period of time. I think you want to keep oxygen away from the surface of the metal if you're trying for a high quality output as well.

Bulhakov
2013-08-05, 03:49 PM
Since you're playing schizo-tech I'd go with something more exotic (consult your GM what level of "exotic" he'll allow).

My idea - bioengineered bone spear:
- almost as strong as steel
- can regrow itself if damaged or broken (e.g. by being soaked in an organic fluid, such as blood or liquefied manure)
- possibly can be reshaped in a similar fashion (or even change shape at will if the GM will allow it), to get some extra effects (e.g. armor piercing, but reduced damage, or extra barbed for damaging flesh)
Suggested looks:
http://archaeology-knigi.com/wordpress/wp-content/uploads/2009/10/8.jpg

Two extra bits of advice:
- tying a harpoon to yourself is generally a bad idea (unless you're spear-fishing while diving), best tie it to your boat, or better yet some sort of winch-pulley mechanism
- talk your GM into a small knife that is intended to be a tool, not a weapon (but is still a much better weapon than being empty-handed)

Edit: also the wire/chain can be some sort of an organic muscle fiber that will contract or expand if pulled in a specific way.