Straight Dope Message Board

Straight Dope Message Board (http://boards.straightdope.com/sdmb/index.php)
-   General Questions (http://boards.straightdope.com/sdmb/forumdisplay.php?f=3)
-   -   What is the heaviest metal available to consumers? (http://boards.straightdope.com/sdmb/showthread.php?t=357911)

Jayrot 02-08-2006 04:52 PM

What is the heaviest metal available to consumers?
 
Here's the background. I build and fly a lot of model airplanes and we often balance them with a piece of lead in the nose. Lead is used, I think, because it's heavy and can be melted down easily and shaped.

Out of curiosity, what is the heaviest metal out there (by size) that can be purchased normally (no plutonium, sorry). I'm envisioning a little BB of some metal that weighs almost as much as a cubic inch of lead.

I remember some thread about office toys and whatnot, and some posters mentioned various, exotic metal hunks that can be purchased on ebay that are curiously heavy for their size.

Any suggestions? Doesn't have to be meltable, but non-dangerous metals would be a plus!

Tapioca Dextrin 02-08-2006 04:59 PM

Quote:

Originally Posted by Jayrot
non-dangerous metals would be a plus!

Dense and non-dangerous? How about a BB made of 24K Gold?

Cagey Drifter 02-08-2006 05:01 PM

you're asking for trouble with this thread title. :smack:

Jayrot 02-08-2006 05:02 PM

Why? Am I going to club someone over the head with some heavy metal, or what?

Cornelius Tuggerson 02-08-2006 05:03 PM

The metal they use for non-DU KEP munitions is called Tungsten . It is not radioactive and is pretty heavy as far as metals go, but might cause leukemia. I figure that is probably your best bet since they like to use the densest materials possible when making tank shells - hence the switchover to depleted uranium.

Jayrot 02-08-2006 05:05 PM

Interesting. Leukemia is no bueno, but lead isn't exactly a walk-in-the-park as is.

Argent Towers 02-08-2006 05:06 PM

pantera

Jayrot 02-08-2006 05:09 PM

Quote:

Originally Posted by Argent Towers
pantera

Nope, that's only 15g (without the case).

Electronic Chaos 02-08-2006 05:20 PM

Quote:

Originally Posted by Jayrot
Why? Am I going to club someone over the head with some heavy metal, or what?


I think he means you'll be getting a few replies like Argent Towers's.

Terminus Est 02-08-2006 05:24 PM

Iridium

AWB 02-08-2006 05:39 PM

Bismuth is one heavier in the periodic table than lead, and the heaviest element that has a stable isotope. Anything element on the table higher than bismuth is radioactive.

charliefoxtrot 02-08-2006 05:57 PM

Quote:

Originally Posted by AWB
Bismuth is one heavier in the periodic table than lead, and the heaviest element that has a stable isotope. Anything element on the table higher than bismuth is radioactive.

Isn't bismuth used as a substitute for lead in shotgun pellets?

Supposed to be less poisonous.

ultrafilter 02-08-2006 06:00 PM

Quote:

Originally Posted by Argent Towers
pantera

Please. Pantera barely qualifies. If you want the heaviest metal out there, go with Electric Wizard or Crowpath. Although I'm confused about the "available to consumers" qualifier--I'm pretty sure everyone wants to sell as many copies of their album as possible.

Seriously, the property you're looking for is density. Otherwise, you could just use a lot of aluminum to get the weight you need. As far as I know, lead is the densest commonly occurring metal.

yabob 02-08-2006 06:31 PM

Quote:

Originally Posted by ultrafilter
...
Seriously, the property you're looking for is density. Otherwise, you could just use a lot of aluminum to get the weight you need. As far as I know, lead is the densest commonly occurring metal.

Probably correct, depending on what you mean by "commonly occurring". The densest metallic element is osmium or iridium depending on which source you read (they are very close at any rate). They are about twice the density of lead, and you could probably obtain some if you wanted to. The problem is that osmium and iridium are precious metals, and a quick check shows that iridium is cheaper currently, only about $200 per troy ounce. Tungsten is very nearly as dense (about the same density as gold), and probably cheaper, since it's an industrial, not precious, metal. Some densities:

Osmium - 22.61 g/cm
Iridium - 22.65 g/cm
Platinum - 21.45 g/cm
Gold - 19.3 g/cm
Tungsten - 19.25 g/cm
Lead - 11.34 g/cm
Mercury - 13.534 g/cm
Silver - 10.49 g/cm

The trouble with tungsten from your point of view is that it's going to be very difficult to work with. It's noted for it's extremely high melting point (3422 C, 6192 F), it's incredibly difficult to machine, and very hard.

Valgard 02-08-2006 06:34 PM

I don't know how easy it is to get your hands on Iridium or Osmium but Platinum is commonly used in jewelry-making and it's got an extremely high density (specific gravity of 21.4, higher than gold and tungsten at 19.3, uranium at 19.0 and lead at 11.3).

So put some Bling On Your Wings :-)

RandomLetters 02-08-2006 06:35 PM

Quote:

Originally Posted by ultrafilter

Seriously, the property you're looking for is density. Otherwise, you could just use a lot of aluminum to get the weight you need. As far as I know, lead is the densest commonly occurring metal.

Gold is quite a bit denser then lead (19.3 grams/cm^3 vs 11.4 for lead) , and while expensive, it is something that a person can obtain by a quick trip to most malls.

Gold is also fairly soft, making it easier to work with then many of the other dense metals like osmium, iridium, tungsten, or platinum.

Q.E.D. 02-08-2006 06:42 PM

Quote:

Originally Posted by AWB
Bismuth is one heavier in the periodic table than lead, and the heaviest element that has a stable isotope.

Not anymore.
Quote:

Bismuth has long been thought to be unstable on theoretical grounds, but not until 2003 was this demonstrated when researchers at the Institut d'Astrophysique Spatiale in Orsay, France measured the alpha emission half-life of Bi-209 to be 1.9 1019 years, meaning that bismuth is very slightly radioactive, with a half-life over a billion times longer than the current estimated age of the universe.
Ok, so it's not going to set off any radiation alarms, but still. ;)

yabob 02-08-2006 06:48 PM

Quote:

Originally Posted by charliefoxtrot
Isn't bismuth used as a substitute for lead in shotgun pellets?

Supposed to be less poisonous.

Yes. Bismuth is generally believed to be comparitively non-toxic. It's pretty dense, which makes it desireable as a substitute for lead shot, but not as dense as lead - 9.78 g/cm. Some studies question the non-toxocity of bismuth:

http://www.news.utoronto.ca/bin6/041115-679.asp

Argent Towers 02-08-2006 07:19 PM

Quote:

Originally Posted by ultrafilter
Please. Pantera barely qualifies. If you want the heaviest metal out there, go with Electric Wizard or Crowpath. Although I'm confused about the "available to consumers" qualifier--I'm pretty sure everyone wants to sell as many copies of their album as possible.

I was joking, hence the small text.

antechinus 02-08-2006 09:42 PM

Quote:

Originally Posted by faldureon
The metal they use for non-DU KEP munitions is called Tungsten . It is not radioactive and is pretty heavy as far as metals go, but might cause leukemia. I figure that is probably your best bet since they like to use the densest materials possible when making tank shells - hence the switchover to depleted uranium.

Quote:

scientists from the CDC and state health departments concluded that exposure to tungsten was not associated with the incidence of childhood leukemia in Fallon
Pubmed

spingears 02-08-2006 09:56 PM

Quote:

Originally Posted by Jayrot
Here's the background. I build and fly a lot of model airplanes and we often balance them with a piece of lead in the nose. Lead is used, I think, because it's heavy and can be melted down easily and shaped.
Any suggestions?

I'd stick with lead, It's economical, easily shaped, cut, etc.

Handle with gloves, respirator when melting, sanding, etc. Minimum hazardous material exposure.
To quote Alfred E. Newman, "What? Me worry?" :smack:

Give the EPA a coronary! :)

wolf_meister 02-08-2006 11:08 PM

[hijack]

Q.E.D.
That is interesting about the half-life of Bismuth 209 (well at my age, it's exciting :D )
On my website I have a time converter that spans a range of units from the Planck time all the way up to the half-life of Bismuth 209, the value of which I found was 2 1018 years. I think that value has been around for decades. Was that the theoretical value to which you referred?
Anyway, if the new value 1.9 1019 years is correct, I guess I'll have to update that converter.

Not only that - think of the marketing potential of that new data:
Bismuth 209 - now with 95% less radioactvity!!!
:: Calling my broker right now to get a good price on Bismuth 209 futures. ::

[/hijack]

David Simmons 02-09-2006 07:24 AM

Quote:

Originally Posted by spingears
I'd stick with lead, It's economical, easily shaped, cut, etc.

Handle with gloves, respirator when melting, sanding, etc. Minimum hazardous material exposure.
To quote Alfred E. Newman, "What? Me worry?" :smack:

Give the EPA a coronary! :)

I'm a firm believer in industrial safety but I don't think it's necessary to go overboard.

Thousands of printers and Linotype operators handled tons of lead in type-metal (lead, tin and antimony) and breathed the fumes from the melted metal for many, many years. I would be interested in seeing life expectancy data showing that they suffered great harm. Ingested lead, such as in lead based paint, can be injurious to small children who tend to eat everything they touch. However adults aren't growing and rapidly developing bone and such and their brains are fully developed and in fact are usually on a downhill curve.

Reasonable precautions: Don't eat it. Don't handle it all day and then lick your fingers, or drink the water you wash your hands in.

yoyodyne 02-09-2006 08:09 AM

You can get osmium or iridium BBs at $31 and $16 per gram. Gold is currently about $18 per gram, and is easily available and workable. Tungsten is cheaper but unworkable. You can get it as small pellets or as fishing weights though. Tungsten used in shotgun shells is an alloy that is designed to bring it to near the same density as lead.

Mr. Goob 02-09-2006 08:31 AM

I've machined tungsten in a lathe. Drilled and tapped the ends and have the coolest darts in the bar.

Yes it's very hard, but with the right tools it's no worse than some of the alloys that have come through my shop. Unless you have access to a machine shop I'd say it would be very tough to do at home.

N9IWP 02-09-2006 09:14 AM

There was a place on the net that sold tungsten cylanders (tho at the time I was aware of them they were out of stock). They also sold magnesuim cylanders of the same size and someone used them as desktop items. Can't find the place now though.

Brian

bradministrator 02-09-2006 09:54 AM

There was a model railroader who weighted N-scale locomotive bodies with depleted uranium to get more traction. This was back in the 70s or 80s, and I believe he worked for a defense contractor.

Ruken 02-09-2006 10:24 AM

Quote:

Originally Posted by yoyodyne
You can get osmium or iridium BBs at $31 and $16 per gram. Gold is currently about $18 per gram, and is easily available and workable. Tungsten is cheaper but unworkable. You can get it as small pellets or as fishing weights though. Tungsten used in shotgun shells is an alloy that is designed to bring it to near the same density as lead.

Iridium is rather inert; I'd go with that. Does anyone know if osmium metal will oxidize in air? The stinky tetroxide is some nasty stuff.

yabob 02-09-2006 11:01 AM

Quote:

Originally Posted by Ruken
Iridium is rather inert; I'd go with that. Does anyone know if osmium metal will oxidize in air? The stinky tetroxide is some nasty stuff.

webelements says:
Quote:

The solid metal is not affected by air at room temperature, but the powdered or spongy metal slowly gives off osmium tetroxide, which is a powerful oxidising agent and has a strong smell.
Note that the name "osmium" came from the "strong smell" of osmium compounds.

The tungsten fishing weights would be a cheaper way to go, and the OP might find some in the right size and shape for his purposes. Unless he has access to a machine shop like Mr. Goob's, he's not going to get them into any other shape. I'd love to see those darts, or, more specifically, pick one up. A commercial fabricator has this to say about tungsten:
Quote:

Tungsten is very difficult to machine and fabricate. With experience, it can be turned. Milling is all but impossible. It is only done with great difficulty and high cost by those most experienced with it. Forming must be done at very high temperatures and with careful stress relieving. Welding is not recommended and riveting is difficult at best. Extreme care must be exercised when designing a component from tungsten. Rembar will readily provide assistance during the design stage upon request. Rembar offers tungsten in powder, sheet, wire, rod, and pressed/ sintered forms. If it is possible to fabricate the part needed from tungsten, Rembar can do it for you.
From http://www.rembar.com/Tungsten.htm

Jayrot 02-09-2006 01:09 PM

Cool, thanks for the responses, all.

Anyone know where I can get 1oz chunks of Iridium? I'd be cool, just for the showoff factor, even if it didn't end up being all the much smaller than a similarly heavy hunk of lead.

Hooleehootoo 02-09-2006 01:19 PM

It appears to me (from this source )that the price of tungsten is around $3/ gram, and from here that the price of gold is about $18/gram. Since the two metals have density that is nearly equal, it would only take a bit of a denser matrial such as Iridium to make something with the density of gold. Then you gold plate it, (to some thickness... maybe a few mm) and you have yourself a pretty good counterfeit. How do people that buy bullion avoid getting taken like this?

Q.E.D. 02-09-2006 01:24 PM

Quote:

Originally Posted by Jayrot
Anyone know where I can get 1oz chunks of Iridium?

Here. Enjoy! :)

Q.E.D. 02-09-2006 01:30 PM

Quote:

Originally Posted by Hooleehootoo
How do people that buy bullion avoid getting taken like this?

It might have the same density, but the electromagnetic signature would be very different. This property is used to detect counterfeit gold bullion and coins, by using a purpose-designed metal detector. It works the same way as discriminating hobbyist metal detectors do to differentiate between valuable items, such as gold jewelry and coins, and buried junk, like tin cans and nails.

Corii 02-09-2006 01:37 PM

Quote:

Originally Posted by Q.E.D.
Here. Enjoy! :)

Here's another source too: http://www.elementsales.com/

yoyodyne 02-09-2006 01:42 PM

Quote:

Originally Posted by Jayrot
Anyone know where I can get 1oz chunks of Iridium? I'd be cool, just for the showoff factor, even if it didn't end up being all the much smaller than a similarly heavy hunk of lead.

They will also cost you about $500 each :)

Q.E.D. 02-09-2006 01:50 PM

Quote:

Originally Posted by Q.E.D.
This property is used to detect counterfeit gold...

That was supposed to read "...could be used..." I don't know for certain whether such a device is actually used for this purpose; there may be other methods that I'm not aware of. Paging samclem!

yabob 02-09-2006 01:59 PM

Quote:

Originally Posted by Q.E.D.
It might have the same density, but the electromagnetic signature would be very different. This property is used to detect counterfeit gold bullion and coins, by using a purpose-designed metal detector. It works the same way as discriminating hobbyist metal detectors do to differentiate between valuable items, such as gold jewelry and coins, and buried junk, like tin cans and nails.

Even not considering this, a couple more points - I doubt that you can buy tungsten in ready made ingots formed to mimic gold bullion, appropriately stamped. You would face considerable expense getting the stuff formed into that shape, given the fabrication difficulties. Also, I suspect a lot of the protection for a gold buyer comes from a non-technical source. I doubt that gold bullion changes hands in any significant quantity without substantial identification and registration procedures. It would be difficult to cover your tracks well enough to prevent getting caught when somebody uncovered the deception.

BTW, if you follow the other links in this thread, $3/gram is very high. I suspect that is for extraordinary purity or specialized forms like wire or foil (your site is a research supply house). The guy selling the "pellets" on EBay is selling them for about $1/gram, and the 1/2 kg "desk weight" cylinders are priced at $99:

http://cgi.ebay.com/ws/eBayISAPI.dll..._BIN_Stores_IT

Chronos 02-09-2006 02:10 PM

For those wondering why bismuth isn't the densest stable element, there are two things which determine the density. First, there's the masses of the individual atoms, and second, there's how far apart the atoms are. How far apart the atoms are in turn depend on the size of the atoms and on the crystalline structure (some arrangements of atoms are more "efficient" than others). Although bismuth has a slightly higher atomic mass, it's forms much less space-efficient crystals, so lead is still denser overall (and gold, tungsten, etc. are denser than lead).

wolf_meister 02-09-2006 03:57 PM

Here's a link to a thread from a few months ago about tungsten:
http://boards.straightdope.com/sdmb/...d.php?t=332945

(I mentioned the fact it has almost the identical density as gold. I guess Q.E.D's electronic detector would foil my plans for that ... darn :( )

Duke of Rat 02-09-2006 04:32 PM

Slight hijack..

Can't you shift some gear forward in the plane and get away from having to use any dead weight??

/slight hijack

Kevbo 02-09-2006 06:04 PM

Quote:

Originally Posted by Duke of Rat
Slight hijack..

Can't you shift some gear forward in the plane and get away from having to use any dead weight??

/slight hijack

Probably not, at least in my experience. One trick is to design them with a overlength nose, but few kits do that, certainly none that are intended to be "scale".

Using a heavy alloy doesn't buy you much unless you have no room for ballast. without having to move your battery aft. However, putting the ballast as far forward as possible does require less of it. I haven't seen them in a while, but you used to could buy extra-heavy brass prop nuts for exactly this reason. You could cast lead-shot epoxy mix into a spinner.

AWB 02-09-2006 08:57 PM

Quote:

Originally Posted by Q.E.D.
Not anymore.

Ok, so it's not going to set off any radiation alarms, but still. ;)

A 19-quintillion year half life? Did they watch a gram of it for 10 years, and 1 atom fissed?

It is strange that 209Bi is so stable, when some of its cousins have a half-life of minutes.

Ale 02-09-2006 09:23 PM

Quote:

Originally Posted by Duke of Rat
Slight hijack..

Can't you shift some gear forward in the plane and get away from having to use any dead weight??

/slight hijack

Even better is building a light tail section; with good planning and a bit of know-how its easy to scrap a lot of unecessary weight from a typical model plane airframe.

Jayrot 02-09-2006 09:34 PM

Bingo. Conventional wisdom is that every gram of weight you add to the tail will require many times that in the nose to balance. We do try to put the gear as forward as possible, but often you have no choice for things like aileron/flap servos which are mounted in the wing, often behind the CG.

Weight is not always a bad thing. It's not uncommon to intentionally add many ounces of weight on a big day to get more momentum going and penetrate the wind better. "Lead sled"

I'm talking high performance gliders here, btw.

Jayrot 02-09-2006 09:37 PM

Also meant to mention that space if often at a premium, especially up in the nose, hence the search for a particularly dense material.

SciPhi 09-19-2016 02:50 PM

Heaviest metals available to consumers
 
This is an old thread, but I thought I'd add this since it answers the OP's question and this thread has a pretty high ranking.

This site has exactly listed the densest metals:

http://www.engineeringtoolbox.com/me...ties-d_50.html

Formatting has been lost in pasting but it's readable. They are obviously not listed in order. On the left is the metal and to the right is their density (in case that wasn't obvious. Based on this list, I would say brass would probably be the most practical. But what do I know?

Metal or Alloy Density
(kg/m3)
Actinium 10070
Admiralty Brass 8525
Aluminum 2712
Aluminum - melted 2560 - 2640
Aluminum - 1100 2720
Aluminum - 6061 2720
Aluminum - 7050 2800
Aluminum - 7178 2830
Aluminum bronze (3-10% Al) 7700 - 8700
Aluminum foil 2700 -2750
Antifriction metal 9130 -10600
Antimony 6690
Babbitt 7272
Barium 3594
Beryllium 1840
Beryllium copper 8100 - 8250
Bismuth 9750
Brass - casting 8400 - 8700
Brass - rolled and drawn 8430 - 8730
Brass 60/40 8520
Bronze - lead 7700 - 8700
Bronze - phosphorous 8780 - 8920
Bronze (8-14% Sn) 7400 - 8900
Brushed metal 7860
Cadmium 8640
Caesium 1873
Calcium 1540
Cast iron 6800 - 7800
Cerium 6770
Chemical Lead 11340
Chromium 7190
Cobalt 8746
Constantan 8920
Columbium 8600
Constantan 8880
Copper 8940
Cupronickel 8908 - 8940
Delta metal 8600
Duralumin 2790
Electrum 8400 - 8900
Eroded metal 7860
Europium 5243
Gallium 5907
Germanium 5323
Gold 19320
Hafnium 13310
Hatelloy 9245
Indium 7310
Inconel 8497
Incoloy 8027
Iridium 22650
Iron 7850
Lanthanum 6145
Lead 11340
Light alloy based on Al 2560 - 2800
Light alloy based on Mg 1760 - 1870
Lithium 534
Magnesium 1738
Manganese 7440
Manganese Bronze 8359
Manganin 8500
Mercury 13593
Molybdenum 10188
Monel 8360 - 8840
Neodymium 7007
Nichrome 8400
Nickel 8908
Nickel 20 8090
Nickel 200 8890
Nickel silver 8400 - 8900
Nickeline 8770
Nimonic 8100
Niobium 8570
Osmium 22610
Palladium 12160
Phosphor bronze 8900
Platinum 21400
Plutonium 19816
Red Brass 8746
Silver 10490
Sodium 971
Solder 50/50 Pb Sn 8885
Stainless Steel 7480 - 8000
Steel 7850
Tin 7280
Titanium 4500
Tungsten 19600
Uranium 18900
Vanadium 5494
White metal 7100
Wrought Iron 7750
Zinc 7135
Zirconium 6570
Yellow Brass 8470

Duke of Rat 09-19-2016 03:21 PM

Heavy metal zombie, and the OP never got the correct answer: The best nose weight is a lighter tail.

Pork Rind 09-19-2016 03:28 PM

Quote:

Originally Posted by David Simmons (Post 7085127)
I'm a firm believer in industrial safety but I don't think it's necessary to go overboard.

Thousands of printers and Linotype operators handled tons of lead in type-metal (lead, tin and antimony) and breathed the fumes from the melted metal for many, many years. I would be interested in seeing life expectancy data showing that they suffered great harm. Ingested lead, such as in lead based paint, can be injurious to small children who tend to eat everything they touch. However adults aren't growing and rapidly developing bone and such and their brains are fully developed and in fact are usually on a downhill curve.

Reasonable precautions: Don't eat it. Don't handle it all day and then lick your fingers, or drink the water you wash your hands in.

Up until about 2 years ago, I had a Linotype and a companion Ludlow Typograph and used, er, screwed around with 'em almost every day. I got my blood tested yearly and never had any lead presence. Metallic lead is just not skin soluble, and you'd only have dangerous fumes if you ran the crucible insanely hot. The casting process would stop working properly long before you hit that spot.

Sorry for the hijack. In the spirit of the thread, I'll note that my darts are 80% tungsten, 20% dunno. Find a set at a thrift store and there's a cheap source of dense metal.

Boyo Jim 09-19-2016 03:48 PM

Quote:

Originally Posted by RandomLetters (Post 7083713)
Gold is quite a bit denser then lead (19.3 grams/cm^3 vs 11.4 for lead) , and while expensive, it is something that a person can obtain by a quick trip to most malls.

Gold is also fairly soft, making it easier to work with then many of the other dense metals like osmium, iridium, tungsten, or platinum.

How much money can you afford to lose if your plane flies over a tree line and never reappears?

Bones Daley 09-19-2016 04:24 PM

The most interesting new use for tungsten carbide IMO is in the production of high-end slides (bottlenecks) and picks for guitarists . http://www.wolframslides.com.

I have held in my hand the Wolfram slide owned by Martin Simpson, and it is unbelievably heavy ... anybody who has seen him play doesn't need to be told what a superb tone it delivers.

If I could afford it I would order one tomorrow.


All times are GMT -5. The time now is 12:54 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

Send questions for Cecil Adams to: cecil@chicagoreader.com

Send comments about this website to: webmaster@straightdope.com

Terms of Use / Privacy Policy

Advertise on the Straight Dope!
(Your direct line to thousands of the smartest, hippest people on the planet, plus a few total dipsticks.)

Publishers - interested in subscribing to the Straight Dope?
Write to: sdsubscriptions@chicagoreader.com.

Copyright 2017 Sun-Times Media, LLC.