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Use of Silver for a Heatsink?

Seoul_lasers

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You can buy Jewellers silver relatively cheaply. $14 per Oz. Alternatively you could also go with CMW® ELKONIUM 22 silver, copper alloy. It's used in high power low loss power connectors. This would be cheaper than going all silver.

DO NOT melt old currency! It's worth a lot more as a coin than just a piece of silver.
 



Wolfman29

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Where can one get CMW ELKONIUM 22 silver, copper alloy? I figure it would be cheaper and probably easier to machine.

Also - where can you get Jeweller's silver? Link?
 

JollyKillBill

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You can buy Jewellers silver relatively cheaply. $14 per Oz. Alternatively you could also go with CMW® ELKONIUM 22 silver, copper alloy. It's used in high power low loss power connectors. This would be cheaper than going all silver.

DO NOT melt old currency! It's worth a lot more as a coin than just a piece of silver.
Historical Silver Data and Charts - London Fix (all the way down the bottom, there is a chart called "Multi year silver" goto the 2000 - 2013)

The spot price is more then double that, the current spot price is $30.29 Au.

How could you possibily get silver lower then spot price from a jeweler?, I once tried to get a ring sized and she wanted to charge me ~$1.5 a gram (~$45 per oz) plus time and work. Jewlers are complete rip-off artists, by the way spot price at the time was ~$29.5 per oz

Also when did you last buy silver?, a few years ago? Well the price has risen considerably, also if you look at the charts I provided, the last time silver was $14 per oz was February 2010 or you could even say September 2009 because Feburary was ~$15.

Or is jeweler silver not real silver?, like german/tibetan silver, I don't know I'm only a PM's investor what would I know.

And I was wanting a pure silver heat sink, both for its great thermal properties and as an investment, can't really do that with copper or the other stuff.
 

Benm

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Silver used in jewelry is normally 925 silver, meaning it contains 92.5% of silver or more. The remainder is probably copper and some other small quantity metals.

In theory you could get an ounce of silver jewelry for 92.5% of the price of an ounce of pure silver if it had no decorative value at all anymore (a crushed ring, something like that).

As far as jewelers being rip offs: The price of silver jewelry is often caculcated by the value of the metal itself, increased with some amount for the craftmanship involved. On a simple ring this markup could be 20%, but on complex jewelry it can be much more than that. On really intricate pieces the markup can exceed the price of the silver.

If the object is something hefty like a silver plate, the value will be very close to the silver price value. For delicate work like decorated earrings, broches and such, it will far exceed the silver value. After all, it would also be costly to fashion those out of metals with little intrinsic value like bronze, or silver plated copper.
 

Seoul_lasers

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Silver used in jewelry is normally 925 silver, meaning it contains 92.5% of silver or more. The remainder is probably copper and some other small quantity metals.

In theory you could get an ounce of silver jewelry for 92.5% of the price of an ounce of pure silver if it had no decorative value at all anymore (a crushed ring, something like that).

As far as jewelers being rip offs: The price of silver jewelry is often caculcated by the value of the metal itself, increased with some amount for the craftmanship involved. On a simple ring this markup could be 20%, but on complex jewelry it can be much more than that. On really intricate pieces the markup can exceed the price of the silver.

If the object is something hefty like a silver plate, the value will be very close to the silver price value. For delicate work like decorated earrings, broches and such, it will far exceed the silver value. After all, it would also be costly to fashion those out of metals with little intrinsic value like bronze, or silver plated copper.
Correct it's generally not pure silver and contains Cu or Sn to make it
easier to work with. Also not as expensive as
pure Ag.
Btw, the AgCu alloy that I mentioned
will need to had at a metal specialty
store or contacting the company directly.
 

Teslanium

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DO NOT melt old currency! It's worth a lot more as a coin than just a piece of silver.
I agree, coins in good or better condition are worth more than their metal content and should be kept as such, but local coin shops may be a source of coins that are too damaged or worn to be of numismatic value, and sometimes can be had at spot (or less if you're lucky).

FWIW, US coin silver is an alloy of 90% silver and 10% copper (recent silver issues such as the 1oz Silver Eagle have a much lower base metal content).

T.
 
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Blord

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I wouldn't melt a 1oz Silver Eagle. The value of the coin is far more than than the value of metal it made of. Buying those dull looking silver bars will be the cheapest solution.



 

chipdouglas

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just a mention... the silver hosts that ryan (strdast) makes us, are not pure silver. I sent him pure silver but he turned it into sterling. Pure silver is too soft for a host. I'm actually a little rough with mine, and sterling is a little too soft for me too.

michael.
 

Seoul_lasers

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just a mention... the silver hosts that ryan (strdast) makes us, are not pure silver. I sent him pure silver but he turned it into sterling. Pure silver is too soft for a host. I'm actually a little rough with mine, and sterling is a little too soft for me too.

michael.
Well alloying Ag with Cu will be your best bet then. It'll have EXCELLENT heat conducting properties as well! It might not be as good as pure Ag, but it'll be so close, you won't care.
Pure silver is a little excessive due to the cost and the fact you'll get tarnish (Silver Oxide) on it. It won't look nice.

---> You can get Sterling Silver blanks and Ingots from jewellery supply stores. Sometimes Jewellers who make their own necklaces have leftover scraps...
Never know.
 

JollyKillBill

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Pure silver is a little excessive due to the cost and the fact you'll get tarnish (Silver Oxide) on it. It won't look nice.

---> You can get Sterling Silver blanks and Ingots from jewellery supply stores. Sometimes Jewellers who make their own necklaces have leftover scraps...
Never know.
Pure silver is only 7.5% more then sterling (if you can get it for spot price) so why not go .999?
Also tarnish isn't "silver oxide" (Ag2O), its "silver sulfide" (Ag2S)
Silver oxide - Wikipedia, the free encyclopedia
Silver - Wikipedia, the free encyclopedia
Silver sulfide - Wikipedia, the free encyclopedia
Tarnish - Wikipedia, the free encyclopedia
http://forums.silverstackers.com/topic-34785-tarnish-and-polish.html
Silver tarnishes by the formation of a layer of Ag2S (tarnish). This layer of tarnish has a relatively uneven thickness and undulating surface at a microscopic level. During tarnish formation, Ag has been consumed from the nice shiny coin surface to build the tarnish layer, and the consumption of silver metal during this reaction is not perfectly even across the coin surface, forming ndulations, pits and a host of other surface imperfections.
When the tarnish is "cleaned" using the galvanic reduction technique (electrochemical), the sulfur is expelled, and the silver from the tarnish is transformed back to it's pure metal form and deposited on the coin surface. However, the silver remains on the surface of the coin in the form of microscopic rough particles, sitting on a now microscopically pitted and uneven metal surface.
This rough silver surface, covered with tiny silver particles is now much more porous, with a lot of tiny crevices, hollows and pits. So, the effective surface area has become relatively much higher, and the crevices and gaps are more conducive to collecting or absorbing any moisture, gases or contaminants that may be around (like a big sponge). Thus, re-tarnishing will occur at a faster rate.
Benm said:
In theory you could get an ounce of silver jewelry for 92.5% of the price of an ounce of pure silver if it had no decorative value at all anymore (a crushed ring, something like that).
I go on ebay (and other online auction sites), garage sales, weekend markets, auctions, estate sales, pawn shops, antique shops, thrift stores/op shops etc, even family and friends to look for SS, I often find silver (and gold, once I found a platinum ring) for much less then what it is worth, eg. I bought A couple of 68g SS spoons at an antique shop for $8 ea, I got a 52oz SS tray for $28 etc. so it doesn't have to be un-wearable or destroyed or crushed to get at spot price or under.
 

Seoul_lasers

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Pure silver is only 7.5% more then sterling (if you can get it for spot price) so why not go .999?
Also tarnish isn't "silver oxide" (Ag2O), its "silver sulfide" (Ag2S)
Silver oxide - Wikipedia, the free encyclopedia
Silver - Wikipedia, the free encyclopedia
Silver sulfide - Wikipedia, the free encyclopedia
Tarnish - Wikipedia, the free encyclopedia
http://forums.silverstackers.com/topic-34785-tarnish-and-polish.html




I go on ebay (and other online auction sites), garage sales, weekend markets, auctions, estate sales, pawn shops, antique shops, thrift stores/op shops etc, even family and friends to look for SS, I often find silver (and gold, once I found a platinum ring) for much less then what it is worth, eg. I bought A couple of 68g SS spoons at an antique shop for $8 ea, I got a 52oz SS tray for $28 etc. so it doesn't have to be un-wearable or destroyed or crushed to get at spot price or under.
Thanks for filling me in on the Tarnish being sulphur related. I always thought of it as oxidation, but I was wrong. Anyways...
Great for finding silver items.
 
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Blord

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You could easily drill a 12mm hole in that ingot. No need to worry about overheating the diode. :D
 

Mrcrouse

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I'd be happy to bore a 12mm hole in that for you. Don't think I'll be able to recover the chips though. ;)
 

Weegidy

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I think that most lasers under 5 watts should be just fine in a well machines copper heat sink. If you're doing something like trying to melt the planet than you might want to consider Ag. :)
 

Seoul_lasers

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I think that most lasers under 5 watts should be just fine in a well machines copper heat sink. If you're doing something like trying to melt the planet than you might want to consider Ag. :)
Correct we are trying to melt the planet. :na:
So pass the silver please.

If you got the money... Silver might be interesting to use. I'll agree copper is just fine.
:lasergun:
 







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