Adding water to Metho what does it do

[Tony]

Nik wrote
(Most definitely do NOT put anything other than metho in it (with the exception of a tiny bit of water, if you're into that method).

After reading a comment by Nik in another thread I am wondering what people think adding water to Methylated Spirits stove fuel is supposed to do. I have been told a few different versions and I would like to find out what other people think it does. eg: I have often been told that it improves efficiency, is this a myth or otherwise.

Clarification: I have done extensive scientific type testing with alcohol stoves using different alcohols and water mixes, I will publish my results soon on BW-T, your comments will help in the writeup.

Tony

[corvus]

Warning re excess water in your Trangia metho ,the brass burner has a wick inside and this can expand if you use too much water causing lack of performance . I always found that running pure metho every now and then whilst being sooty usually rectified the problem.
corvus

[Son of a Beach]

A very small amount of water added to the metho makes it burn a little cleaner (ie, less soot to clean off the bottom of your pots). This is what the the Trangia people tell you in their instructions, anyhow. In my experience, I think it works, a little, but not enough for me to worry about.

I went through a phase of doing it, regularly, but if you refill your metho before completely emptying it, how do you know how much water is left in it. If the water sinks to the bottom, and the metho floats on the top, and you add more metho, AND add more water, have you then doubled the amount of water that was in there? This appeared to be the case, and after two or three refills, you could end up with quite a lot of water in there which could then cause problems with the internal wick (as corvus said), and of course make the metho burn too cool.

After having tried a little water with the metho for a while, I decided it wasn't worth the effort. The little soot that does get onto the pans scrapes off fairly easily anyhow.

[Franco]

It depends on what type of alcohol you are burning. It is my understanding that in Europe most of the alcohol there (ethanol) has a purple dye that cause the formation of soot and the 10% or so of water counteracts that. I experimented adding water to the 95% pure ethanol we have here to "cool" the output of the White Box stove. I did that after I realised that in the US most burn methanol. The result was a smaller "bluer" flame. (my problem was a too wide flame for my 13cm wide pot)
During my tests it appeared that adding water did also slow down the boil but I retained the same total burn time using 10-15% less fuel.
Franco

[Tony]

Hi Corvus, franco and Nik,

Thanks for your replies, I was unaware of a wick inside the Trangia burner until Corvus pointed it out, I eventually found it it is very small and I am wondering what it is supposed to do.

It was a public holiday in Canberra yesterday and I spent the day in my shed doing tests with my old Trangia 27 on methylated spirits/water mixtures. The results are leaning toward that water added to Methylated Spirits does improve efficiency as to why.

During my tests it appeared that adding water did also slow down the boil but I retained the same total burn time using 10-15% less fuel.

Franco thanks for your test results they confirm my results, adding water does slow down the heating process and this does help improve the efficiency but something else is happening which I have been unable to put my finger on yet.

I have certainly read that adding water to alcohol reduces the soot the accumulates on the pot, and I have yet to do some tests to confirm this. I personally like my pots to be blackened on the bottom and shiny on the sides, BW-T forum users interest as to why, this paper is very interesting # Heat Losses in a Cook Pot at Constant Temperature Alan Berick, Aprovecho June 10, 2006 it can be obtained from http://www.aprovecho.org/web-content/pu ... s/pub2.htm.

Tony

[Son of a Beach]

I was unaware of a wick inside the Trangia burner until Corvus pointed it out, I eventually found it it is very small and I am wondering what it is supposed to do.

I think it's much like a wick in an oil/kero lamp. It draws a small continuous feed of fuel from the reservoir close to the flame where it can get very hot, and burn and/or vapourise at the targeted point at the top of the wick. In the case of a Trangia burner, you want the metho to vapourise as close to those little holes as possible, so that it burns as vapour as it passes through the holes, not as liquid sitting in the middle/bottom of the reservoir. I'm guessing a bit here, but I think that's the principal.

[corvus]

Wick in Trangia is for the reason Nik mentioned that's why some instructions for "Tuna Can Stoves" call for a wick

[Tony]

Thanks Nik and Corvus,

thanks for your explanations, I am learning a lot from this exercise.

I asked a friend in the US who designs and makes wicked alcohol stoves, if he had seen a Trangia wick and he sent me some pictures from a burner that he had cut up and his explanation of what he thinks it does it does. I have posted his pictures in case others would like to see what is inside a trangia burner.

I would like to thank Zelph from bplite.com (he makes some nice lightweight alcohol stoves too)

Tony

There are some very nice closeup photos of the wick. My thoughts are the material bring up the fuel along side the hot walls/rim of the stove and keeps it there until it's all used up (capillary action). The series of photos show how the stove was taken apart. I'll get you the url's and you can post them on the forum you mentioned. Let me know if you want them and I'll pm them to you.

http://img.photobucket.com/albums/v228/ ... ion015.jpg
http://img.photobucket.com/albums/v228/ ... ion014.jpg
http://img.photobucket.com/albums/v228/ ... ion013.jpg
http://img.photobucket.com/albums/v228/ ... ion010.jpg
http://img.photobucket.com/albums/v228/ ... ion009.jpg
http://img.photobucket.com/albums/v228/ ... ion006.jpg
http://img.photobucket.com/albums/v228/ ... ion005.jpg
http://img.photobucket.com/albums/v228/ ... ion004.jpg
http://img.photobucket.com/albums/v228/ ... ion003.jpg

[james cav]

This may have been covered but water and metho mix just fine as they are both polar compounds for lack of a beter word. Metho is just ethanol or alcohol if you prefer. They dont split or form layers they are just happy to be mixed. Hmm could have used liquids thats a better word! hehehe.

[corvus]

Unlike a Single Malt which needs a few drops of water to release the tension of the alcohol

[lexharris]

Metho is just ethanol or alcohol if you prefer.

With a small amount of methanol added to made it undrinkable, hence the name, methylated spirits. Methanol is poisonous, ethanol is not (although that may be debatable after a heavy night on the turps.. ) In some countries metho is called denatured alcohol I think.

[lexharris]

Unlike a Single Malt which needs a few drops of water to release the tension of the alcohol

Do you find it really needs that much water?

[Tony]

Hi Lex,

Metho is just ethanol or alcohol if you prefer.

With a small amount of methanol added to made it undrinkable, hence the name, methylated spirits. Methanol is poisonous, ethanol is not (although that may be debatable after a heavy night on the turps.. ) In some countries metho is called denatured alcohol I think.

Thanks for that information, Australian, British and NZ Methylated spirits seems to be about 95% ethanol but US Denatured alcohol is a completely different story, there seems to be a no standard mix, I have seen denatured alcohol data sheets with ethanol content as low as 30%, 50% Ethanol is common and high concentrations of methanol is also common, 92% ethanol content is the highest content I have seen in the US. Denatured alcohol is not available in Canada, they only can get Methanol, which has only about 2/3rds of the heating energy of Ethanol.

Methanol is not the only addative to methylated spirits, it also has water and Methyl isobutyl ketone, fluorescein, methyl alcohol* or denatonium benzoate. The additives in Metho are nearly imposable to distil out.

Tony

[corvus]

Sheech with all those additives no wonder my soup was undrinkable when unbeknown to me some meths had leaked into the billy and dried prior to me using it

[lexharris]

Denatured alcohol is not available in Canada, they only can get Methanol
Tony

Surprising, I thought MeOH was not at all good for you. But then again my wife came home from the supermarket with some "fabric rust remover" a while ago. Works really well she said. I checked the ingredients - 8% HF. How these things get on the supermarket shelves I do not know.

[lexharris]

For the boffins amongst us, these Wikipedia entries make interesting reading:
http://en.wikipedia.org/wiki/Methylated_spirit
http://en.wikipedia.org/wiki/Methanol
http://en.wikipedia.org/wiki/Ethanol

[Tony]

Hi Lex,

Denatured alcohol is not available in Canada, they only can get Methanol
Tony

Surprising, I thought MeOH was not at all good for you. But then again my wife came home from the supermarket with some "fabric rust remover" a while ago. Works really well she said. I checked the ingredients - 8% HF. How these things get on the supermarket shelves I do not know.

You are right Methanol is very toxic both to drink and inhale the fumes both burnt and un-burnt, I have done a series of stove efficiency tests using Methanol and got headaches and felt sick from doing them.

Tony

[lexharris]

Sheech with all those additives no wonder my soup was undrinkable when unbeknown to me some meths had leaked into the billy and dried prior to me using it

Hey corvus, it's probably a good thing the soup was undrinkable, that methanol can have some nasty effects. But then again if you DID drink it ..... here's an extract from Wikipedia:

"ethanol can be used to treat methanol poisoning by blocking the enzyme until the body can excrete enough methanol through the kidneys, lungs and skin. In a documented case, a ship worker poisoned while cleaning out a methanol tank was successfully treated with administration of a good portion of the liquor in the ship's "medicine chest."

So I guess all Trangia users should always carry a good portion of single malt in case of accidental metho poisoning....

[corvus]

Changed to gas after that experience-still carry medicinal spirits tho

[hikin_jim]

After reading a comment by Nik in another thread I am wondering what people think adding water to Methylated Spirits stove fuel is supposed to do. I have been told a few different versions and I would like to find out what other people think it does. eg: I have often been told that it improves efficiency, is this a myth or otherwise.

Clarification: I have done extensive scientific type testing with alcohol stoves using different alcohols and water mixes, I will publish my results soon on BW-T, your comments will help in the writeup.

Tony

Tony,

Did you ever get a chance to post the results you mention in your post (above) anywhere? This is a subject I am quite interested in.

HJ

[Orion]

Jim, here's the thread you were looking for: http://bushwalk.com/forum/viewtopic.php?f=15&t=1440

Tony published his results in full on backpackinglight.com: http://www.backpackinglight.com/cgi-bin/backpackinglight/alcohol_fuels_part_two.html

[hikin_jim]

Jim, here's the thread you were looking for: http://bushwalk.com/forum/viewtopic.php?f=15&t=1440

Tony published his results in full on backpackinglight.com: http://www.backpackinglight.com/cgi-bin/backpackinglight/alcohol_fuels_part_two.html

Thank you!

HJ

[Tony]

After reading a comment by Nik in another thread I am wondering what people think adding water to Methylated Spirits stove fuel is supposed to do. I have been told a few different versions and I would like to find out what other people think it does. eg: I have often been told that it improves efficiency, is this a myth or otherwise.

Clarification: I have done extensive scientific type testing with alcohol stoves using different alcohols and water mixes, I will publish my results soon on BW-T, your comments will help in the writeup.

Tony

Tony,

Did you ever get a chance to post the results you mention in your post (above) anywhere? This is a subject I am quite interested in.

HJ

Hi HJ,

Orion beat me to it, you will find part one interesting too http://www.backpackinglight.com/cgi-bin ... t_one.html

Happy reading.

Tony

[hikin_jim]

Tony (and Roger Caffin):

EXCELLENT work. I'm sure I've read those two articles on BPL in the past, but it's helpful to be away from an article, get some additional field use and experiments in, and then re-read the articles in light of one's experience.

The main conclusions of the 2nd article are quite practical:
1. Don't waste flame up the sides up the pot. Water up to 25% may be used to control the flame.
2. Don't bother with IPA, it's a nasty waste of time
3. If you can't get a decent ethanol based fuel, use methanol.

HJ

[Tony]

Tony (and Roger Caffin):

EXCELLENT work. I'm sure I've read those two articles on BPL in the past, but it's helpful to be away from an article, get some additional field use and experiments in, and then re-read the articles in light of one's experience.

The main conclusions of the 2nd article are quite practical:
1. Don't waste flame up the sides up the pot. Water up to 25% may be used to control the flame.
2. Don't bother with IPA, it's a nasty waste of time
3. If you can't get a decent ethanol based fuel, use methanol.

HJ

Hi HJ,

With those conclusions you just about have it nailed it with alcohol, with pot diameter vs flame diameter, a pot that is around 2-4 cm larger diameter that the visible flame diameter is around optimum and that goes for center flame stoves and side flame stoves, I have not tested flame diameter vs pot diameter with canister stoves, the results might be different.

I decided that with any fuel or weight saving that adding water to alcohol fuel will give is so small, it is not worth the effort.

Tony

[hikin_jim]

... with pot diameter vs flame diameter, a pot that is around 2-4 cm larger diameter that the visible flame diameter is around optimum and that goes for center flame stoves and side flame stoves...

Ah. I didn't realize that I'd need that much "clearance." Interesting. Thank you for that.

I've basically given up on side burners. People talk about how efficient the Jim Wood's Super Cat is. Efficient? Really? I've never been able to get much in the way of efficiency from one, and I've experimented with a couple of different configurations of the basic design. To it's credit, it is very light, very easy to make, and you don't need a separate pot stand.

I decided that with any fuel or weight saving that adding water to alcohol fuel will give is so small, it is not worth the effort.

Agreed. It's amazing the lengths that some Ultralighters will go to in order to make some strange alcohol set up work. I want something like a Trangia burner: pour in the fuel into a nice big opening, strike a match, and away you go. No priming, no small fueling openings, no fiddly bits. I was a bit interested in water, but then thought better of it because of the fiddle factor. Then I read part two of your BPL paper on alcohol that you did with Roger. Adding water just doesn't seem like it pays.

My current area of research is a light weight alcohol stove that burns high ethanol content alcohol cleanly and efficiently without water. I've been working with a local stove designer. We think we've got a good design, but we need to do more testing. Hopefully, it'll come to something.

HJ

[South_Aussie_Hiker]

Adding water to metho what does it do

Stoves which produce black, sooty smoke are not completely combusting all the alcohol, just like a car running extremely rich. It means there's not enough oxygen to complete the combustion process.

Adding water essentially slows the stove down a little - and hence there is enough oxygen to ensure complete combustion.

Less unburnt/incompletely burnt fuel being wasted = more efficient.

Same concept on a gas hiking stove - place your finger (completely at your own risk ) over one of the air holes on the stove neck while it's running - the flame will flicker and probably start producing soot - because not enough oxygen is getting to the gas. You may also lose the hair on the back of your hand if you aren't careful.

[sailfish]

If the water sinks to the bottom, and the metho floats on the top, and you add more metho, AND add more water, have you then doubled the amount of water that was in there? This appeared to be the case, and after two or three refills, you could end up with quite a lot of water in there which could then cause problems with the internal wick (as corvus said), and of course make the metho burn too cool.

Alcohols (methanol, ethanol) are soluble with water. The water does not separate on the bottom but is dispersed evenly in solution. However the boiling point of these alcohols are lower than that of water so only a proportion of the water is boiled away with the fuel vapour causing the concentration of water in the remaining fuel to rise.

Ken

[Son of a Beach]

I used to add a little water to the metho in my Trangia (when I still used metho). But my reasons were not the efficiency. I did it solely to stop the black soot building up on the bottoms of the pans. They stay quite clean when a bit of water is used.

Once they get sooty, the soot gets onto everything the bottom of the pot touches, sometimes making a real mess of things. This is frequently a problem if you have two pots where one fits into the other (like the Trangia) resulting of the inside of one pot getting soot in it.

[Orion]

My current area of research is a light weight alcohol stove that burns high ethanol content alcohol cleanly and efficiently without water.

You mean this doesn't already exist?

With all of the metho/ethanol stove users in the world you'd think it would be easy to point to a "go to" stove, if not a whole raft of them, that worked reliably and had the fuel-air mixture right. I fiddled briefly with a few ethanol stoves this past year (Trangia, Penny, Cat) and none of these worked all that impressively.