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Stoker53
04-01-2005, 14:10
Just pulled the ebay trigger on an alcohol stove. I've done a quick search on WB and didn't get my answer. So I'll go ahead and ask.

Is there a significant performance difference..... iso vs ethyl? I suspect that they are both about equal but would love some input from the experts.


Thanks in advance.

Footslogger
04-01-2005, 14:12
I would only use Isopropyl as a last resort in an alcohol stove. It smokes and will blacken your pot and does not burn as hot as denatured alcohol.

'Slogger
AT 2003

Oracle
04-01-2005, 14:19
Stoker53,

If you can, go to a hardware store, and they will usually have what is listed as "denatured alcohol" in the paint section. This works very well. You can buy Heet in the yellow bottle from gas stations and automotive stores (be sure to buy the Heet that's in the yellow bottle only). And, as a last and most expensive resort, Everclear and Golden Grain can be bought at many liquor stores, and will work as well.

neo
04-01-2005, 20:21
you can use heet,or any other fuel line antifreeze,just make sure regardless
of brand that its methal or methonal not isoprophl,usually around a dollar
anywere that sells gasoline,if you are ever in kent ct,denatured is 30 cents an
oz at the outfitter,its 3.50 for 32 oz in the hardware store,i paid .79 cents
for 12 oz of fuel line antifreeze at the gas station,happy trails to ya:cool: neo

minnesotasmith
04-01-2005, 22:43
http://www.whiteblaze.net/forum/showthread.php?t=2607&page=1&pp=20&highlight=ethanol

I'd stay away from methanol/methyl alcohol unless it's deep winter due to being such a nasty poison, even then denatured ethyl alcohol sold for stove fuel will usually work fine. The ones that have as additives one or more of methanol, methyl ethyl ketone, methyl isoketone, etc., should work in deep winter fine. They won't be as poisonous if you spill some on you/inhale the vapors, will still light in most cold weather, and will give off more heat per volume than mostly methanol fuel will. Note that some paint strippers will say on the container that they also work as alcohol stove fuel. The yellow HEET bottles of gas line antifreeze are methanol, while the red iso-HEET are isopropyl alcohol without added water.

The problem with isopropyl, such as rubbing alcohol, is that above all it has 30% water. It's wasted weight to haul. Also, relatively pure isopropyl (whether or not water is added) may well have some issues igniting in very cold weather; pure ethyl alcohol will have less trouble igniting in cold weather than isopropyl does, and methanol even less trouble. Isopropyl (if without much water) will have somewhat more heat value when burned than will ethyl, which will have far more than methyl.

I'm working on an article on this subject for WhiteBlaze, but it's not done yet. I worked as the lab manager at a couple of ethanol production plants, so have a certain amount of professional knowledge on this subject that I'm happy to share with my fellow forum members.

minnesotasmith
04-02-2005, 09:57
Worth more discussion IMO.

Stoker53
04-02-2005, 10:16
Thanks MS....as a chem major myself I'm gonna avoid high methyl alc blends and just stick with denatured ethyl or PGA. Methyl alc scares me! It's even dangerous if you spill in on your hands. Initially I'm only going to use the stove for solo weekend jaunts but I am a little fascinated with these little stoves and can see why so many people use them. My very 1st backpacking stove as sterno and a folding metal box with a chrome grill on top. Guess I've come full circle.

I do have access to 99% IPA ( company I used to work for bottles alc - Swan Brand ) in large qtys from their outlet store. I may give that a try, a home, to see if I can live with a little soot vs higher IPA BTUs.

minnesotasmith
04-02-2005, 12:22
That's because its boiling point is closer to many of theirs, plus I understand it's made from different (less simple) precursors than are industrially-synthesized lower alchohols. The heavier stuff may not burn as easily, although if it does, it will yield even more BTUs (ergs for continental Europeans) than IPA does. The lower pet distillates can aid in ignition; even pure ethanol can get cranky about ignition below 45o F air temp if it's cool too, and IPA is even more persnickety.