View Full Version : Making an alcohol flame VISIBLE
Shiraz-mataz
01-14-2006, 14:06
After finishing my first Pepsi can stove I couldn't wait to take it to work and show it to my fellow geeky engineer friends. We took it outside at lunch, put a little alcohol in it and fired it up! Or was it fired up? We couldn't tell! The only way we knew for sure that the side burner holes had ignited was by holding a little piece of paper next to them. Unsatisfactory! Being safety-minded, I started to wonder if there was some way to make the flame visible with an additive.
A few Google searches later landed me on a chemistry web site where they discussed this same problem in a lab for high schoolers. It said to make the alcohol flame visible, add 10 grams of table salt to 1 liter of alcohol. After working through a long series of conversion factors I came up with more manageable units of just under half a teaspon of salt per cup of alcohol.
I mixed up a little batch and noticed that salt does not dissolve easily in alcohol. I had to kind of mush it up like a mortar and pestle. I put about half an ounce of the mixture in the Pepsi can stove and lit it off. Sure enough, it bloomed into a beautiful orange flame! It was noon and my alcohol stove was churning away with a very visible ring of fire. There was no noticeable degradation in performance but after it burned out I found a very slight powdery residue inside the can. I can only assume that is from the salt. I've only done the test one time so far so we'll see if continued use of salt clogs the ports or not. In the meantime, if you're concerned about the safety of using alcohol stoves because you can't see the flame, here is one way to solve the problem.
Does anyone else have experience using salt, or some other additive, to make an alcohol flame visible?
saimyoji
01-14-2006, 14:21
One thing to consider: adding salt will increase the rate of oxidation (rusting) of your stove/pot. Will it make much difference in the life of the stove/pot??? :-?
Lanthar Mandragoran
01-14-2006, 18:34
One thing to consider: adding salt will increase the rate of oxidation (rusting) of your stove/pot. Will it make much difference in the life of the stove/pot??? :-?
Maybe if you're using a stainless pot, my guess is that fire causes it to proceed even more rapidly.
The main benefit I see from this is for 'testing' flame patterns...
I found using alcohol stoves in a small puddle of fuel on a wooden table or shelter floor seemed to make the flames QUITE visible in a short time.
Of, course, there WAS the limitation of those black rings that resulted......:dance
Blue Jay
01-14-2006, 20:10
Damn, if this gets out there will be no hikers without eyebrows for me to laugh at. Thanks for nothing, people are always spoiling my fun.:banana
jasonklass
01-15-2006, 12:22
You could use popcorn salt from the supermarket. It's really fine and will probably dissolve faster than regular salt.
After finishing my first Pepsi can stove I couldn't wait to take it to work and show it to my fellow geeky engineer friends. We took it outside at lunch, put a little alcohol in it and fired it up! Or was it fired up? We couldn't tell! The only way we knew for sure that the side burner holes had ignited was by holding a little piece of paper next to them. Unsatisfactory! Being safety-minded, I started to wonder if there was some way to make the flame visible with an additive.
A few Google searches later landed me on a chemistry web site where they discussed this same problem in a lab for high schoolers. It said to make the alcohol flame visible, add 10 grams of table salt to 1 liter of alcohol. After working through a long series of conversion factors I came up with more manageable units of just under half a teaspon of salt per cup of alcohol.
I mixed up a little batch and noticed that salt does not dissolve easily in alcohol. I had to kind of mush it up like a mortar and pestle. I put about half an ounce of the mixture in the Pepsi can stove and lit it off. Sure enough, it bloomed into a beautiful orange flame! It was noon and my alcohol stove was churning away with a very visible ring of fire. There was no noticeable degradation in performance but after it burned out I found a very slight powdery residue inside the can. I can only assume that is from the salt. I've only done the test one time so far so we'll see if continued use of salt clogs the ports or not. In the meantime, if you're concerned about the safety of using alcohol stoves because you can't see the flame, here is one way to solve the problem.
Does anyone else have experience using salt, or some other additive, to make an alcohol flame visible?
Heh heh... show off...
Get one of you engineer friends to hold their hand over it! :D
Maybe add a little bit of white gas or diesel? Recently Patrick showed us what happens with pure white gas, but I'm thinking maybe 70 or 80% alcohol, rest gasoline, or something else.
I figure this will be an exciting (maybe even dangerous :D ) experiment, especially at dusk when the glow will be more visible. So before I try this, have any of you been down this road?
Stag,
MIXING fuels, now you're talking...
Shiraz-mataz
01-17-2006, 11:28
UPDATE...
I thought the idea of mixing in a little white gas sounded good so yesterday I put a splash of white gas (about 10 drops) in with the alcohol. This was a quickie test so I'll repeat it with more accurate measurements. The results looked promising. The flame was now at least visible due to the presence of the white gas but was not out of control as seen in straight-gas tests. Definitely more convenient than trying to get salt to dissolve and no residue in the burner. I'll keep you all posted.
i just shut off the light in my workshop.
i've used the 'wooden table' method too, accidentally, but like the original poster, didn't like the black residue (burn marks?)
there's also the epidermal-phalangal thermometer method, but it's slightly painful. still a useful backup though, when you're in the woods and can't turn off a light...:D
MacGyver2005
01-17-2006, 16:03
Hey man, we both live in the same area! And, we are both engineers! Do you work on base? Shoot me an email or a PM, my email is JMcAlister @ Gmail.com. My father and I completed our Thru in 2005, it would be cool to meet up with someone else. I hope to hear from you soon.
Regards,
-MacGyver
GA-->ME
Shiraz-mataz
01-17-2006, 16:07
Hey man, we both live in the same area! And, we are both engineers!......
:bse HA! I was hoping there'd be a neighbor in this forum! Look for an email (Gmail) from me.
Danny
MacGyver2005
01-17-2006, 20:50
:bse HA! I was hoping there'd be a neighbor in this forum! Look for an email (Gmail) from me.
Danny
Danny, email probably bounced because I put spaces in my email when on a public forum so that it does not get "harvested" by third parties. PM sent, you should be able to get email to me know.
Regards,
-MacGyver
GA-->ME
Just did the first test of this mixture. One was 1 table sp of HEET and and 1/2 tea sp of coleman. Second was 1 table sp of HEET and 1 tea sp of HEET (I think this is about 75% HEET--3 tea = 1 table??).
The flame was visible and did not flare up, really a mild flame IMO.
Next step is try it in the stove.
BTW, be careful trying this - I burned the hair on my fingers during the first light.
mweinstone
01-18-2006, 21:31
to check if a stove is lit hold you hand far above and move down till you feel warmth.i get mad when anyone gets burned and i get mad when people mix fuels and i freak out and grab the fuel bottle and take it away and i tell your teacher on you.please be more carefull .dont waste time mixing fuel when allways following saftey first rules work so well to keep us alive. one of your fuels could seperate and if you loaded up your stove with it that would be that.
Well, yeh, caution and safety need to come first. The idea of using gasoline with alcohol is not new. Maybe 10 years ago Arco marketed blends of gasoline with methanol and ethanol for use as motor fuel. The reason they added gasoline was to make the flame visible. A car wreck with 20 gallons of burning methanol could be a real problem for the fire fighters.
Best I recall, Arco's blend was 80% alcohol and 20% gasoline--brand names M80 and E80. So, I doubt Arco would market a product that had the potential for separation. That said, your point is still well taken.
I know how to check for the flame. The singing (not a burn) happened when the match was used to light the fuel. Actually this is common around fires. So, I switched to longer matches--problem solved.
Especially with kids and hikers with too much JD, having an invisible flame is IMO a bad idea.
Stag
Shiraz-mataz
01-20-2006, 17:39
I've just posted photos from my side-by-side comparison tests of making an alcohol flame visible. Check them out here...
http://www.whiteblaze.net/forum/vbg/showimage.php?i=9821&c=516
I feel that adding salt resulted in the best flame in that it was visible and NOT out of control. The alcohol with white gas added was obviously visible but it was generating a big plume of flame which is probably not desirable. The only down-side to adding salt can be seen the the adjacent photo which details the residue left inside the Pepsi can stove.
Dances with Mice
01-20-2006, 20:56
As a scientist I appreciate the way you set up your experiment, executed it, and presented your results. It is obvious you have no agenda other than the pursuit of truth. Kudos, sir, on a job well done.
Your photo shows the stove with the alcohol/gas mixture burned with less control than the stoves with pure alcohol & alcohol/salt. I accept your conclusion as most probably true, but wonder if you’ve considered whether the photo may show the effects of the fuel mixture rather than the true flame pattern of both stoves?
In other words, how can you determine the flame pattern of the alcohol stove? You can’t, it’s invisible under the conditions of the photograph. Based on your photo nobody can determine the flame pattern of alcohol stoves. Agreed?
Considering that, does the alcohol/salt photo represent the entire flame pattern? Nobody can say since you’ve already shown that some alcohol flames are invisible at the photo conditions. Does that make sense? I’m not saying you're wrong….I’m just saying…
So then does the alcohol/gas mixture make the entire flame pattern visible, or does it make more of the flame pattern visible? Again, nobody can say.
And finally the most important question (to a scientist employed by private enterprise): Who cares?
Seriously. So what? Which fuel mixture in that stove boils water faster, or with less fuel, or more reliably under difficult circumstances like high winds or cold temperatures? That's really what your audience wants to know.
Shiraz-mataz
01-20-2006, 21:34
Seriously. So what? Which fuel mixture in that stove boils water faster, or with less fuel, or more reliably under difficult circumstances like high winds or cold temperatures? That's really what your audience wants to know.
Actually, my reason for delving into this was centered on safety. I like the novelty of a homemade stove, and I think using alcohol as a fuel is cool. It kind of goes against the grain for someone like me who cut their teeth on propane and white gas! But you're presuming that my "audience" only cares about the topics you mentioned. Granted, reducing weight, increasing reliability and improving performance are all worthy tasks but my first inclination was to alter parameters that would affect visibility of the flame in daylight conditions. In my job, safety is paramount, and that was my motivation here.
My one "control" was the 100% alcohol stove and I tried two variables for improving visibility. I think the results were actually pretty telling and worthwhile. As a follower of the scientific process I know that this is only the first step. Having seen the flame pattern of the 100% alcohol stove in the dark, I know it compares favorably with the salt solution. (Maybe photos of those two would be good to see?) The next step would of course be a performance test. You'll have to stand by for that - give me some time, geez!
Dances with Mice
01-20-2006, 21:42
Well done. You did establish the question you wanted to answer, then did it. Thank you for reminding me.
I answer the question of "is it lit?" by using a pine needle dunked into the stove's alcohol to light the stove. When the pine needle suddenly burns, the stove is lit. And knowing alcohol, once the stove is lit it will stay lit. Further testing risks loss of eyebrows.
Shiraz,
Good pictures-your alcohol/gas flame looks out of control. When I did my test, I concluded that I needed a different hole size/pattern for the stove. It looks like smaller holes, but more of them, might help. Seems like there is just too much fuel available to burn with the gas/alky mixture in a conventional alky stove. Watch some one light off a MSR with white gas and you can see some super big flames if too much fuel is used for priming.
I am off to my stove research laboratory to try some nem stove ideas.
Oh yea, be really careful with this stuff--it could get a lot worse than no eye lashes.
atraildreamer
06-11-2006, 17:23
Try Diamond Crystal salt...very fine. :p
Gasoline & alcohol...get your affairs in order. :eek:
The 80/20 gas/alcohol blend was sold as "Gasahol" in the 70's, right after the first oil embargo. :(
Use some JB weld to adhere a small length of nichrome wire in an arch from one side of the stove to the other. (wire diameter to be .oo5 or there abouts) If there are flames, their heat will cause the wire to glow red hot. Red Hot wire DO NOT TOUCH-DO NOT ADD FUEL
I use fiberglass wicks for my alcohol stoves(open flame). I soak them in a saturated solution of "Twenty Muleteam Borax" mixed with water. Take them out and let them drip dry overnight.
Causes the flames to be Azure Blue. Kinda like the color that the copper sulfate makes:confused:
I'm going to use your suggestions nhalbrook.