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  #1  
Old 08-15-2013, 02:16 PM
Protocon Protocon is offline
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Tungsten Carbide- HOW DO I GATHER LARGE QUANTITIES!?

Hey Everyone!

I am a science fiction writer and am wondering where I would find a decent amount of Tungsten Carbide to melt down?

Enough to make 10 spikes? 2 and a half feet long, and 2 and a half inches wide. For sabot rounds.

I heard that if I melt tungsten trioxide with graphite, then I can create Tungsten Carbide. SO where do I get tungsten trioxide in large quantities? I'll figure out the graphite part myself...

How the hell do I get this stuff? Besides drill bits. If I could find a garbage bin filled with drill bits to melt down would that work?

These are simple and basic questions for something very complicated, so if you can't help it, feel free to express sarcasm or annoyance. I've got a thick skin.

Thanks everyone!

Last edited by Protocon; 08-15-2013 at 02:19 PM..
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  #2  
Old 08-15-2013, 02:24 PM
Mangetout Mangetout is offline
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Are you actually looking to obtain the stuff, or want to write a realistic scenario about obtaining it.

Either way, you can buy it in bulk from metal/alloy merchants.
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  #3  
Old 08-15-2013, 02:25 PM
Dewey Finn Dewey Finn is offline
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Well, you could just buy tungsten carbide. McMaster-Carr has it in the form of balls, rods or flat stock. Judging by the prices, though, your spikes are going to be expensive.
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  #4  
Old 08-15-2013, 02:27 PM
Habeed Habeed is offline
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What's the setting? Tungsten carbide isn't heavily regulated (versus depleted uranium), so your protagonist could just order some from here : http://www.alibaba.com/showroom/tungsten-carbide.html

Note that some of the listings on that link are big pieces of the stuff that you could presumably machine into sabot rounds. Your protagonist is going to need some specialized machine tools to do this, of course, and then casting equipment to pour the molten iron around the tungsten carbide spikes...

Also, since you're basically talking cannon ammo, he's going to need to build a cannon barrel and source himself a large quantity of propellant. I don't think the propellant is hard to obtain, since hand-loaders do it all the time, but making a pre-stressed cannon barrel doesn't sound easy.

Frankly, he might have better luck trying to steal a cannon from a national guard armory or something. Those places are minimally guarded with only a chain link fence with razor wire, typically. As I understand it, the tanks and mobile artillery are minimally guarded (maybe a few padlocks on the controls), it's the ammunition that is in a vault-like bunker and well protected. I'm actually not completely certain, I've seen the video were a man stole a tank, and I know that the armories I went to had minimal protection, however, the armories I've personally been at only had light vehicles. It's possible the armories that have tanks have better protection.

Last edited by Habeed; 08-15-2013 at 02:31 PM..
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  #5  
Old 08-15-2013, 02:30 PM
DCnDC DCnDC is offline
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A shit load of drill bits.
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  #6  
Old 08-15-2013, 02:30 PM
pravnik pravnik is offline
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Out of curiosity, how are you planning on melting them? Tungsten carbide has a really high melting point, around 5200 Fahrenheit, and tungsten trioxide melts at around 2700 Fahrenheit.
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  #7  
Old 08-15-2013, 02:33 PM
Protocon Protocon is offline
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Wow thanks a lot for the replies! This is why I go to this thread when I need to know weird shit.

There is no buy or purchase in this scenario. The government has withdrawn from that part of the world, as have all corporations and business.

So could the characters just end up finding a large supply of tungsten carbide in an old war factory?

Now that this might seem plausible, should my characters just find all the materials, already manufactured, necessary to assemble these tank rounds?


I would've liked to illustrate the process of manufacturing the rounds, but perhaps actually finding the rounds, whether assembled or not, seems much more realistic.

What do you guys think?

Last edited by Protocon; 08-15-2013 at 02:35 PM..
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  #8  
Old 08-15-2013, 02:35 PM
Habeed Habeed is offline
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I think he'd have to machine them from a rod into the sabot shape on a lathe. The tough part is what cuts tungsten carbide?

And the second part is melting lead and pouring it into a mold in the shape of a round of ammo.

Both sound technically doable, I know the tools to do all this can be bought somewhere.
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  #9  
Old 08-15-2013, 02:37 PM
Habeed Habeed is offline
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What does he need the tungsten carbide FOR? The only use for it is building a round of ammunition that can pierce armor. However, there's MUCH easier ways : this is a popular method : http://en.wikipedia.org/wiki/Explosi...med_penetrator

These are much easier to make, I think, and they don't require a cannon to fire them. The big ones, possibly built in Iran, have destroyed numerous American vehicles in Iraq. They will go through the armor on an Abrams.

Last edited by Habeed; 08-15-2013 at 02:38 PM..
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  #10  
Old 08-15-2013, 03:25 PM
Dewey Finn Dewey Finn is offline
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OK, I didn't realize this was a fictional scenario. Given the extremely high temperatures needed to melt it, why would the characters be attempting to make rounds out of tungsten carbide, instead of something more easily obtained and with a lower melting point?
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  #11  
Old 08-15-2013, 03:46 PM
Protocon Protocon is offline
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I didn't think regular steel would work for the perpetrator spike inside of a a sabot round. Would it work? Thought I needed something a lot stronger.

Were fighting gigantic war droids. Picture a war of the worlds type robot, just as tall. Lets say they are less armoured then a tank.

I think I might just go with the scenario that all this stuff is just found. Like I said I was really keen on illustrating how to make a sabot round but... can't do everything I guess. Some things just aren't believable.

Thanks again!!

Last edited by Protocon; 08-15-2013 at 03:51 PM..
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  #12  
Old 08-15-2013, 03:52 PM
The Great Sun Jester The Great Sun Jester is offline
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Well, if you're willing to pay the right price there's always...Skald.

War droids are easy: something sticky and corrosive with founder's sand mixed in for abrasion--aim for the joints. And wait.
Quote:
Originally Posted by Habeed View Post
I think he'd have to machine them from a rod into the sabot shape on a lathe. The tough part is what cuts tungsten carbide?
Diamond and, I think, ruby.

Last edited by The Great Sun Jester; 08-15-2013 at 03:56 PM..
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  #13  
Old 08-15-2013, 03:56 PM
aNewLeaf aNewLeaf is offline
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Quote:
Originally Posted by Protocon View Post
I didn't think regular steel would work for the perpetrator spike .
Please please please use that term somewhere in the story.
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  #14  
Old 08-15-2013, 03:59 PM
Cheshire Human Cheshire Human is offline
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Quote:
Originally Posted by Protocon View Post
So could the characters just end up finding a large supply of tungsten carbide in an old war factory?

Now that this might seem plausible, should my characters just find all the materials, already manufactured, necessary to assemble these tank rounds?
It's expensive stuff. Unless the place was highly industrialized, the government collapsed suddenly, and everyone was in a 'bug-out, save yourselves' situation, someone would have salvaged it and sold it where civilization still exists, rather than abandon it.
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  #15  
Old 08-15-2013, 04:06 PM
Habeed Habeed is offline
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Ok, so it's giant robots. IEDs that use EFPs are the ONLY thing that sounds like a survivable weapon. If you point a cannon behind a barricade (tank destroyer style) or a tank cannon at one of those robots, and fire, there's numerous possible sensors the robots can use to detect you.

They can detect the muzzle flash, which is a distinct signature if you use a ultraviolet and IR sensor in parallel and compare the output...

They can detect the incoming cannon round via radar, like used on certain Russian tanks.

They can engage the incoming round with explosive reactive armor.

They can return fire at the people who shot at the robot, with both direct and indirect fire. If the robots are networked, even if you kill one robot, you're still dead.

We don't have giant robots today, but we do have drones and attack helicopters, and this is about how it goes today. Anyone who does something overt like hold/fire a large weapon when an attack helicopter or drone is nearby generally dies. Running for cover doesn't help. See this video for an example : https://www.youtube.com/watch?v=7TZOxlTwAvA

An IED on the other hand, especially if it uses a hard wired detonator, is much harder to detect and far more survivable for the operator.

If you want your protagonist to survive for the sequel, he better have drones or small robots of his own...

Last edited by Habeed; 08-15-2013 at 04:10 PM..
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  #16  
Old 08-15-2013, 04:28 PM
Protocon Protocon is offline
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Quote:
Originally Posted by Habeed View Post
Ok, so it's giant robots. IEDs that use EFPs are the ONLY thing that sounds like a survivable weapon. If you point a cannon behind a barricade (tank destroyer style) or a tank cannon at one of those robots, and fire, there's numerous possible sensors the robots can use to detect you.

They can detect the muzzle flash, which is a distinct signature if you use a ultraviolet and IR sensor in parallel and compare the output...

They can detect the incoming cannon round via radar, like used on certain Russian tanks.

They can engage the incoming round with explosive reactive armor.

They can return fire at the people who shot at the robot, with both direct and indirect fire. If the robots are networked, even if you kill one robot, you're still dead.

We don't have giant robots today, but we do have drones and attack helicopters, and this is about how it goes today. Anyone who does something overt like hold/fire a large weapon when an attack helicopter or drone is nearby generally dies. Running for cover doesn't help. See this video for an example : https://www.youtube.com/watch?v=7TZOxlTwAvA

An IED on the other hand, especially if it uses a hard wired detonator, is much harder to detect and far more survivable for the operator.

If you want your protagonist to survive for the sequel, he better have drones or small robots of his own...
Godamnit. Hahaha. Ok, well. Listen I'm just trying to draw something epic. Trust me, when It's all over it will be drawn very epic. I appreciate the knowledge. i have never been in the military and quite frankly, I'll admit I have no idea what I'm talking about.

These droids look cool, but quite honestly I think any jet from the modern day would annihilate them. They still look fucking awesome though.

It's like pacific rim, right? Big robots sounds dumb as hell, but its not about the logistics, its about how awesome it looks.

Thing is, I just need to know how to acquire the hardware necessary to shoot something down. In the end, it's gonna look so badass, I swear.

So yeah. I just wanted to know some facts about how to acquire this stuff. Thanks a lot everybody!

Last edited by Protocon; 08-15-2013 at 04:29 PM..
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  #17  
Old 08-15-2013, 04:32 PM
gotpasswords gotpasswords is offline
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Hardware stores and jewelry shops are where I'd be looking for pieces of tungsten carbide.
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  #18  
Old 08-15-2013, 06:34 PM
the_diego the_diego is offline
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You don't melt and cast tungsten carbide. Read on powder metallurgy and sintering technology.
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  #19  
Old 08-15-2013, 06:53 PM
excavating (for a mind) excavating (for a mind) is offline
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As has been mentioned, Tungsten Carbide melts at an incredibly high temperature. Someone isn't likely to be able to melt and cast Tungsten Carbide without a dedicated facility for such a purpose.

First, a source of tungsten carbide. Old machine cutting tools. Cutter inserts. Manufacturers collect the broken inserts for recycling as the scrap cost is rather high. Perhaps your characters could find an abandoned scrap supply or raid a manufacturing center.

Second, they would have to crush the used inserts. A big hammer and lots of pounding. Smaller than pea gravel. Between the size of peppercorns and sand. It'll take a lot of pounding, but the stuff is pretty brittle, so if you hit it hard enough, you will break it up.

Finally, you would want a binder. Commercially, they use nickel (that is how the inserts themselves are made, with a very fine powder (almost flour consistency) mixed with nickel powder and pressed into shape and sintered around 2000F. Plenty hot, but a forced-air charcoal fire will do it.

For fiction, they could take coins, which are an alloy of nickel and copper, grind them up for a powder, mix it with the pulverized machining inserts and press it into a mold of the required shape. Although very delicate, the pressed forms would hold together well enough to go to a air-blast charcoal furnace to heat them high enough to get the nickel-copper powder to fuze with the tungsten carbide powder. Dimensional control wouldn't be the best, but you could grind to size once cooled.

Now, for non-fiction, this might not work, you would need the crushed tungsten carbide to be the consistency of sand or finer and the nickel powder would need to be much purer than ground-up coins, but I'd guess that the number of people who would be able to tell you what effect of the high copper content would be is very small, perhaps less than 10,000 people in the US, while the number of people who would agree with the basic steps would number in the hundreds of thousands, if not millions.

That is, it would probably work for a Sci-Fi novel. Certainly more believable than a universal translator. If scientific accuracy is of utmost importance, have your characters find a store of tungsten carbide and nickel powder from a manufacturer of the cutting inserts, and then they just have to mix them, press them in a mold, and sinter the blanks.
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  #20  
Old 08-15-2013, 08:47 PM
the_diego the_diego is offline
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You can make a 1 1/2 inch diameter sub-caliber sabot round to fire through a 90mm gun. The round doesn't have to be pure TC. Just the head. So find a way to sinter-forge a 37mm to 50mm bodkin head and attach a forged steel shaft.

I don't know how strong a nickel cement TC sinter would be. I think this will do for cutting tools and drill bits but might not be impact-resistant enough for artillery sabot rounds. The more accepted cementing metal is cobalt, itself pretty hard and strong.
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