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My Tungsten Cube (2019)

thume.ca

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Re: My Tungsten Cube (2019)

#161

Post by dvaun »

MgB2 wrote: post #129

I used to work with tungsten carbide cubes during my PhD thesis. They're used in multianvil high-pressure synthesis. With the right setup you can reach almost 20 GPa of pressure. Not as much as with diamond anvil cells, but you have more reasonable sample sizes (a few milligrams). And thats still like the pressure pretty deep into Earth's mantle. I also used the opportunity to snap a neat picture of a polished WC cub…

> They have the mean tendecy to explode into super sharp pieces when you're not expecting it, so wear goggles.

Well, I guess I need to buy a new wedding ring at some point.

Re: My Tungsten Cube (2019)

#162

Post by 6nf »

cwkoss wrote: post #27
Avshalom wrote: post #3

Gotta say I love the ad copy for the 10 pound cube: ADD to your collection! This cube is the larger version of the world famous tungsten cube COMPARE the density to our 2.5" Aluminum cube to enhance the experience

I wonder if anyone is manufacturing tungsten dumbbells. Would be very pricy, but also super cool.

'Official' sports kettlebells are all the same physical size but are available in a wide range of weights. For sizes 8kg to about 32kg they just use steel. For heavier ones they use lead. The very heaviest kettlebells contain tunsten.

Re: My Tungsten Cube (2019)

#163

Post by tyingq »

mbreese wrote: post #123
Taniwha wrote: post #101

Earlier quoted context omitted.

https://luciteria.com/metal-cubes/iridium-metal-cube-9995

To save people some time clicking through... A 10mm cube of Iridium weighs ~21.9g. And from this source, costs $9000. From the same source, a single gram is only $275. This means that due to the difficulty in working with this very dense metal, the cost of turning the Iridium into a cube is nearly $3000 (on top of the ~$6000 for the metal itself)!

Osmium would be heavier still (22.59 grams/cc), and a relative bargain at $1275 for the 10mm cube at the same source. Not polished/shiny though.

Re: My Tungsten Cube (2019)

#164

Post by MisterTea »

We use blocks like this in our electron beam welders to set the beam power, shape and focus on older machines (newer machines use a CPU/DSP controlled system). A small 25x25x50mm block sits on an adjustable height stand which is set to the height of the weld joint. You dial in the settings, hit the block with the beam and using the optics, visually check the focus and alignment. Then you move to the weld joint and start welding. For big power jobs we break out "the brick" which is 75x50x155. Its so heavy you need two hands to hold it and sometimes two people to place and line it up in the vacuum chamber.

Tungsten is the only metal you can reliably use as our machines have beam powers up to 15kW which can precisely deliver an enormous amount of heat into a pencil point sized area. Even at the common 1-3kW ranges the tungsten instantly liquefies when the beam turns on. Ive seen 1/2 thick aluminum turn into a puddle while the tungsten just gets a dent in it. You'd think copper is a good second bet but nope. Its good at heat sinking but melts way quicker.

Re: My Tungsten Cube (2019)

#165

Post by tyingq »

lacksconfidence wrote: post #157
anonporridge wrote: post #131

Earlier quoted context omitted.

It's not like that money disappears. Just think of it like buying gold bullion. Unlike say, a $9000 motorcycle impulse purchase, a block of raw metal should hold it's inflation adjusted value relatively well for decades and you can sell it whenever to recoup the money.

Gold bullion has a healthy market to sell back into though.I don't know the numbers, but i wouldn't be surprised if I could easily sell gold for 80% of "market" value, whereas probably closer to 20% for something like Iridium that has a very small adressable market unless I were to expend considerable effort finding someone willing to pay what it's worth.

Platinum might be a better fit in this "really heavy" category. 21.447 grams/cc versus gold at 19.3 grams/cc.

Re: My Tungsten Cube (2019)

#166

Post by hencq »

silisili wrote: post #78
SoylentYellow wrote: post #34

Earlier quoted context omitted.

I'm surprised the EMTs did not know how to remove the ring. Squeeze it with locking pliers and it will break into pieces.

Similarly, if missing pliers, you should be able to set it on a hard surface(like concrete or metal) and give it a few tough taps with something hard. They shatter shockingly easy.

Considering that in this case there's a finger inside the ring, I'm not sure if that's such an amazing idea.

Re: My Tungsten Cube (2019)

#167

Post by 6nf »

jacquesm wrote: post #106
dharmab wrote: post #88

Earlier quoted context omitted.

This sounds like an urban legend. "Ring cracker" tools are widely available, and can be improvised from common tools.

Scene of an emergency: hold still while I figure out how to improvise a ring cracker that can crack a solid tungsten ring without further injury to your finger.

There's videos showing exactly how to do it using vice grip pliers available in any hardware store, it's very easy and takes 20 seconds.

Re: My Tungsten Cube (2019)

#168

Post by silisili »

hencq wrote: post #166
silisili wrote: post #78

Earlier quoted context omitted.

Similarly, if missing pliers, you should be able to set it on a hard surface(like concrete or metal) and give it a few tough taps with something hard. They shatter shockingly easy.

Considering that in this case there's a finger inside the ring, I'm not sure if that's such an amazing idea.

Just use lighter taps :).

See: https://www.youtube.com/watch?v=yN71I3PKR6g

Re: My Tungsten Cube (2019)

#169

Post by jacquesm »

6nf wrote: post #167
jacquesm wrote: post #106

Earlier quoted context omitted.

Scene of an emergency: hold still while I figure out how to improvise a ring cracker that can crack a solid tungsten ring without further injury to your finger.

There's videos showing exactly how to do it using vice grip pliers available in any hardware store, it's very easy and takes 20 seconds.

Yes, it is. If you have vice grips handy. Emergencies tend to happen 'just like that', you don't get to prepare ahead of time unless you want to accessorize your tungsten ring with a pair of vice grips in your pocket.

Re: My Tungsten Cube (2019)

#170

Post by paulgerhardt »

fywacro wrote: post #145
MgB2 wrote: post #129

I used to work with tungsten carbide cubes during my PhD thesis. They're used in multianvil high-pressure synthesis. With the right setup you can reach almost 20 GPa of pressure. Not as much as with diamond anvil cells, but you have more reasonable sample sizes (a few milligrams). And thats still like the pressure pretty deep into Earth's mantle. I also used the opportunity to snap a neat picture of a polished WC cub…

FYI, tungsten carbide (tungsten + carbon) is a different substance from the pure metal tungsten... They have very different physical properties. But I do appreciate your story about tungsten carbide, too :-)

If anyone knows where to get a tungsten cube I would be interested. I’ve wanted one since reading this post a few years ago but every vendor usually sells alloys.
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