Any one ever melt a penny with there stove. I made a penny stove two days ago and after starting to burn I didn't like it, tryed something new. Well I decided to move the penny over to let more fuel out of the center hole to speed up the burn. I wanted to move on to another stove but not while this one was still burning. It was a very slow burn, jets too small. When it finally burned out I decided I would much rather be cuddle up with my wife so I went to bed. Well I looked at my penny yesterday and it had melted during the burn. It looks cool. You can see where the copper started to peal back and the, I guess, nickel is showing through.


PS. sorry for such a long post.

Any one ever melt a penny with there stove.
Not likely. The melting point of copper is 1984 deg. F, aluminum is 1220 deg. F so the stove would melt long before the penny. Alcohol doesn't burn that hot.

That would be accurate if the penny was still made out of mainly copper. The modern penny is ~97% zinc with ~3 percent copper coating. Zinc has a melting point of 785 deg. F, so it is possible to melt the zinc before melting the aluminum

That would be accurate if the penny was still made out of mainly copper. The modern penny is ~97% zinc with ~3 percent copper coating. Zinc has a melting point of 785 deg. F, so it is possible to melt the zinc before melting the aluminum
Forgot about changing the composition of the penny. You're right. Anybody know how hot alcohol burns in such a stove?

alcohol burns hot enough to melt an aluminum V8 stove. Aluminum melts at 660°C or 1220°F. I know I melted one of my stoves. Lesson 1, never burn your side burning aluminum stove without a pot of something on it.

HuuMMMMM, something is not computing. the closest I can come to how hot alcohol burns is 425°C or 797°F. The worst grade of aluminum seems to be melting at about 850°F. How can 797°F melt 850°F? Well, IT CAN"T. what is wrong with this picture? :-?

HuuMMMMM, something is not computing. the closest I can come to how hot alcohol burns is 425°C or 797°F. The worst grade of aluminum seems to be melting at about 850°F. How can 797°F melt 850°F? Well, IT CAN"T. what is wrong with this picture? :-?Maybe because the can is an aluminum alloy? Alloys have different properties.

Found this
http://www.gsig.com/lasers/tech_tips/tech_tip_7.html
3000 series alloys are Al-Mn alloys. They are also soft but not as much so as the 1000 series. 3000 series alloys are often used for containers that need to be drawn by a die yet still retain some strength. Probably the most common example is the aluminum beverage can, but they can also be used for battery cans, transducer packages, etc. 3000 series have good corrosion properties.

HuuMMMMM, something is not computing. the closest I can come to how hot alcohol burns is 425°C or 797°F. The worst grade of aluminum seems to be melting at about 850°F. How can 797°F melt 850°F? Well, IT CAN"T. what is wrong with this picture? :-?
lug nut,

Could the answer to your question be buried in semantics?

As you know, melting point is the temperature at which a solid becomes a liquid. In your example, you state that melting point is 850F.

When one describes their stove as having "melted", has it really been transformed into a puddle, or has it been heated to the point of deformation?

Well no matter how hot your stove burns, I am holding in my hand right now one burnt up Penny.

Good point Roland.

Just wanted to add that beverage can lids are made from 5000 series aluminum.

Alligator,

1000 series Aluminum start to slowly melt - at 900-1100( melting point -1250 for pure 1100 Aluminum). there are those times of bad material. I done Third party inspection and have inspected bad stainless pipe or wrong chemical compostion - Niton

Bending Aluminum does weaken it, also what fuel was he using. Denatural may have been part of the cause.

Well no matter how hot your stove burns, I am holding in my hand right now one burnt up Penny.

Neato! Can you post a photo?

Bending Aluminum does weaken it, also what fuel was he using. Denatural may have been part of the cause.

I used only heet. I will post pictures this weekend of my poor penny. I have been carrying it around for the last two days in my pocket. People can't believe this little grey metal was a penny.

very good point, Roland. I will amend my statement to say "My stove was severely deformed, not melted" I was burning methyl alcohol. I still can't nail down how hot alcohol burns at. there are so many variables that muddle the calculations. Anyone have just a general range of °F?

Remember that the alcohol is vaporized in these stoves, thereby mixing it with oxygen...burning LIQUID alcohol burns at a certain temp...add oxygen by vaporizing the alcohol, and burn under pressure.... what happens to the temps then?

did a search supertroll and found this:
1. Flame temperatures depend upon so many factors that it is impossible to
reliably put a number on it. The temperature will depend upon the
composition of the vapor and air, the configuration of the fuel source,
the speed of the air, and so on...
2. I assume it is ethanol. If it is isopropanol the numbers will be
about the same. The ignition limits of ethanol are 3.28 -- 18.95 vol.
(alcohol/vol air)x 100. The Henry's law constant for alcohol is about 200
mol/l*atm. If Henry's law applies to the sanitizer the same as it does for
water. (You can assume this if, as I believe, the sanitizer is
predominantly water + alcohol + thickener) then a 10 gm /liter
concentration of alcohol (I just guessed about what this concentration
is.) is 2.17 moles/liter. Henry's law is: C =
Kh*P, where P is in (atm) and C is in (mol/l). So P = C/Kh = 2.2/200 =
0.01atm. Using the ideal gas law: PV=nRT 0.01 atm corresponds to:
n/V=0.01/0.082*298=4x10^4 mols/l The molar density of air (M.W. = 28) is
(n/Vair)= 1atm/0.08*298= 0.04 mol air/l.
So the Valc. / Vair ratio is 4x10^-4/ 0.04=0.01mol
alc./mol.air. The lower ignition limit for ethanol is 0.0328.
So the estimate of the sanitizer vapor pressure is somewhat lower
than the ignition limit. You might check with the manufacturer, but it
appears not to be a fire risk. Also there are regulations regarding the
ignition limits of a product. If ignition were a problem, they could not
ship the stuff by common carrier -- which I doubt.

Vince Calder

well, that sure cleared things up for me, eh? :D

Remember that the alcohol is vaporized in these stoves, thereby mixing it with oxygen...burning LIQUID alcohol burns at a certain temp...add oxygen by vaporizing the alcohol, and burn under pressure.... what happens to the temps then?

Except that is is physically impossible to 'burn liquid' ALL flame is cause by the vaporization of the liquid prior to combustion. Even in the case of a wood-fire, the solid itself doesn't burn, the volatile organics do (the ash left over is nonvolatile organics... btw a gassifier is so effecient because it volatilizes everything possible very effeciently).

However, as Lug Nut alluded to, Combustion Thermodynamics is extremely complicated and rarely understood. Suffice it to say stating that some burns a ### deg F is a complete misnomer. What CAN be said is that combusting a fixed amount of material releases a fixed amount of heat energy. How fast it combusts, and the concentration of space (aka reduced physical volume) within which it combusts will both elevate the apparent temperature that results.

(censored) this post (censored):eek: (censored) who the (censored)(censored)(censored)(censored) melting point......(censored) boiling point:rolleyes:
(censored)(censored)!!!!:D

hold in candle flame with pliers for about two minnuts.me and my son did this for pyro practice when he was like, 7 .great fun for the whole family.my personal fav is flattening coins on the tracks. now thats entertainment.

In high school, we sanded the very edge of a penny so we could see the nickel inside, then dropped it into a solution that reacted with the nickel and left the copper alone. The next day, we had an empty shell of copper. Man, that was a blast. Sort of.

I bet somebody on here even knows what the solution was, because I have no idea.

Man, this thread has wandered.

Still waiting on pics of the melted penny, though!

Rather obtusely technical and more complex than what follows; but, what happened was that due to the different coefficients of thermal expansion between the copper [plating] and the zinc exacerbated by formation of oxides and the concommitant oxide ablation in both metals the copper pulled loose from the zinc then due to the stresses in the thin and now surface oxidized copper plating layer it curled/further separated giving the appearance of its having apparently melted - all of which can occur well below the melting points of the initially relatively pure materials [oxide melting points are considerably higher]. [B]More correctly and succinctly put it burned rather than melted. Copper-zinc layer differential stress is basically the principle/phenomena used in bi-metallic thermostat designs [without the separation] and the oxidation analogous to the much more intense oxy-accetylene burning of steel whereupon the steel is literally set on fire by the abundance of oxygen and the additional exothermic heat of rapid oxidation.

Got pictures of my melted penny. My camera is only 3.2 mega pixeles but it shows my poor penny next to a shinny unburnt one.

http://whiteblaze.net/forum/vbg/files/8/5/0/2/100_0266.JPG

http://www.whiteblaze.net/forum/vbg/showimage.php?i=11581&c=694

PS. I will try tp get better nes to see closer. For now this is what I have.