cast your own heat sink!

[john_lawson]

UHmmm GEEK here

 

[chopper]

Correction:  299792458_ms = speed of light

you mean m/s...not milliseconds

 

[ElektroFreak]

[quote author=299792458_ms link=1227164847/20#30 date=1227222899]Correction:  299792458_ms = speed of light

you mean m/s...not milliseconds [/quote]

See..........only a geek would know that  

 

[scopeguy20]

The two things that occur to me are;
Why Aluminum?

Why not casting bronze, coin silver, (90%), or sterling silver, 92.5% or brass?

These metals are easy to obtain, cast at lower temperatures and will transport or wick heat as good or better than Aluminum, so why use Aluminum?

 

[thebucketmouse]

The two things that occur to me are;
Why Aluminum?

Why not casting bronze, coin silver, (90%), or sterling silver, 92.5% or brass?

These metals are easy to obtain, cast at lower temperatures and will transport or wick heat as good or better than Aluminum, so why use Aluminum?

No reason in particular, other than that aluminum seems to be the most easily available. Where can I get a small amount of these metals?

 

[ElektroFreak]

bronze and brass should be easily found in your house right now... you can find scraps of both types of silver at any jeweler. I'd imagine most jewelers have a fair amount around that is unsuitable for jewelry, and they probably would let it go cheap...

 

[Mohrenberg]

[quote author=scopeguy20 link=1227164847/20#35 date=1227227784]The two things that occur to me are;
Why Aluminum?

Why not casting bronze, coin silver, (90%), or sterling silver, 92.5% or brass?

These metals are easy to obtain, cast at lower temperatures and will transport or wick heat as good or better than Aluminum, so why use Aluminum?

No reason in particular, other than that aluminum seems to be the most easily available. Where can I get a small amount of these metals?
[/quote]

i thought the other thing that absorbed heat better than aluminum was gold and diamond?

anyways, i just melted down a cheap clip i had that went to a crappy .22 rifle i bought at wal-mart..... aluminum is easy to find.......
are pennies made of pure copper??? if so just melt some of those......
or your mom's jewelry

 

[pullbangdead]

Old pennies are cure copper, newer pennies have a zinc core that is then covered with copper. The zinc actually melts at a lower temperature than the copper too, so you can get the zinc out of it and have zinc and copper both separated.

But there are actually laws against destroying money nowadays, because the actual value of the metal in some coins is getting very close to, or surpassing, the face value of the coin. If it wasn't illegal, you could turn a VERY good profit just by going to the bank, buying rolls or coins, melting them, and selling the metal. At the moment, the metal itself in both US nickels and US pennies is worth more than the face value of the coin. http://www.usatoday.com/money/2006-12-14-melting-ban-usat_x.htm

And as far as being better heat absorbers, there are a couple of things that go into how good a heatsink is, it's not just one simple value. Generally, good conductors make good heatsinks, but that's not all there is to it as far as material properties go.

 

[thebucketmouse]

How would you separate the zinc from the copper?

 

[pullbangdead]

Make sure you're somewhere that molten metal won't do any harm when it falls and splatters, on top of a bucket of sand should be ok. Hold it with a safe pair of pliers and just use a butane torch or something like that that gets hot enough to melt the zinc (about 700K), and the zinc should melt and run out before the copper gets too soft. Maybe cut it in half or something like that to let the zinc out easier.

I THINK I've seen someone do it before without cutting it, possibly the copper got soft enough that it deformed and let the already-liquid zinc out, and the expansion of both the zinc and copper due to heating maybe helped? But it's been a long time, so I really don't remember.

But the zinc will melt at just a little more than half of the melting temperature of the copper, so it shouldn't be hard to melt one without melting the other and let the liquid follow gravity.

 

[Balisong]

Coin silver is rather rare to find just in your change though....but silver is the best conductor found naturally. Also, you have to remember that aluminum melts much lower then all the other metals mentioned, so that still may be the best choice because it will not require as much to melt.

 

[Dark_Horse]

Another "molten-metal" safety-tip: Water-can be a a real problem around high temperature-liquids. If you accidently let even a single-drop of water fall into your crucible, the water will be turned into steam violently, it can spatter the molten-metal around at lower temps like with lead, but it can be like a bomb with molten-aluminum. If you choose to experiment with this stuff, it is really important to check out the safety-items first. Lasers can blind, this is true, but a foundry can really mess you up.
**gets off soap-box**
DH