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jayw288
06-26-2014, 10:22
I just made myself a fancy feast stove the other day and had a question regarding how much fuel I need. I'll be using it in the morning to boil water for coffee and in the evening to boil water for food. How much fuel would I need for 3-4 days of use? Or how long would an 10oz bottle of fuel last using it twice a day to boil water?


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Odd Man Out
06-26-2014, 10:39
I think you will need to test it for yourself. The efficiency of your system is based not just on the stove, but also on the pot and windscreen you are using. I would put the amount of water in the pot that you need to boil (first for breakfast and then for dinner). Load up the stove with more than enough fuel to boil that. Then time to see how long it takes to boil and how long it takes for the flame to go out. For example, if you find that with 2 oz of fuel, you boil your water in 4 minutes but the flame goes out in 8 minutes, then you probably need about 1/2 of your fuel (1 oz) for breakfast.

Keep in mind that real life conditions (wind, air temp, water temp, etc) will affect the boil times, making it difficult to guess the right amount of fuel to use. Guess too low and you run out of fuel before your water is hot enough. Guess to high, you will have more fuel than you need and waste the extra. Consider that if you are only heating water for coffee in the AM, you may not need to bring it to a boil, depending on how you make your coffee and how hot you want it.

Another option it to make a device to snuff the flames so that excess fuel can be retrieved. This takes some of the guess work out of how much fuel to use, but pouring unused fuel out of a cat food can stove can be tricky. Getting an device to suck fuel might be a good idea if you go this route. Some balk at taking extra stuff, but if it allows you to use fuel more efficiently, then in the long haul, it may be a good investment. Sort of a personal preference thing.

Another option, is to get a rough estimate of how much fuel you will need with some simple testing and then take twice as much as you need. Then when you get back, measure how much fuel you used and calculate the average daily use. With practice, you will find out what is appropriate for your system. For 3 to 4 days, the amount of extra weight you carry until you get your system tuned in won't be a back breaker.

Testing is part of the "fun" of stove building!

Deco
06-26-2014, 10:50
I generally assume one "feast" can of fuel per meal. Admittedly I like to take my time during meals and keep my water warm for tea and such. By assuming one can of fuel per meal I assure myself a little extra fuel. 16 oz of fuel will last me about 10 days so I would think your 10 oz would suffice for a 3-4 day trip.

Ricky&Jack
06-26-2014, 10:51
Yeah, if you don't have time to experiment by trying the stove out at home (you can just add an ounce of fuel, place your pout on top, and see if it is enough to boil or not) then Just buy a regular 10oz bottle of Heet with you, and use it on the trail. that should be more than enough for a 3-4 day trip.

Then when you return, you will know exactly how much to take next time

jayw288
06-26-2014, 11:05
Thanks for the ideas. I'll probably pick up a can of fuel from home depot and have some fun this weekend. There's a state park 15 minutes away and I love an excuse to take a overnight trip.

Damn Yankee
06-26-2014, 12:22
I used my FF stove a few weeks ago while SW fishing with my brother. I filled the can with fuel to the bottom of the lower row of holes, used a wind screen and it took about two oz. of fuel because of the wind conditions.

FarmerChef
06-26-2014, 15:35
I use a penny stove so not a direct comparison. Definite +1 on the testing method recommended by OMO and yes, various factors will affect your burn time/btu output. As for reclaiming fuel, I can snuff mine out with the lid of a can (also serves as the base of the stove) and then pour through one of the burn holes back into the HEET bottle. The hole makes a nice "spout" and a tiny stream of fuel that is easy to pour. The FF will be slightly messier with the big holes but if you pour carefully you could work it out. Knowing how much fuel to use in advance and with experience will make this much easier over the long haul.

garlic08
06-26-2014, 18:01
Another thing to keep in mind to save fuel is that you don't really have to boil the water. I remember from chemistry that extra heat is required to get water to actually boil after reaching 212F (delta H vaporization). If you're going to cook pasta, 210F, say, is good enough, and you'll save fuel. Again, that's part of experimenting with your stove. Some hikers use pot cozies to save fuel, too.

Another factor with alcohol is the breakeven point of fuel weight. I've heard different numbers, but many agree that if you routinely carry more than 10 ounces of alcohol, you might be better off with gas. It all depends on your hiking and camping style.

Turk6177
06-26-2014, 18:15
I use the same stove. 3 to 4 days should be between 6 and 8 ounces cooking twice a day. I fill my stove until the liquid is just below the bottom holes in the stove. This generally enough to boil two cups of water and then some.

jayw288
07-04-2014, 19:40
After some experimenting with a couple different alcohol stoves I think I'm going to stick with my MSR Micro Rocket. At 3.5oz it really isn't saving much weight to switch to alcohol. I made a coke can stove which did better in boil time (16oz water to boil) and total burn time (2oz of alcohol burn to end) compared to the fancy feast. But neither were anywhere close to the MSR. For the few oz of weight addition, I like my MSR.

zelph
07-07-2014, 08:50
I had some thoughts the last 2 days after reading the comments in this thread on what I didn't like about the fancey feast SuperCat stove.

When removing the pot, the stove stuck to the bottom of the pot. When the water boils you have a natural tendency to remove the pot. Some alcohol is still in the stove and sometimes the stove will release from the pot and fall to the ground with flames spreading far and wide.

The boiling alcohol causes a seal to occur between pot and rim of stove.

July
07-07-2014, 09:19
I had some thoughts the last 2 days after reading the comments in this thread on what I didn't like about the fancey feast SuperCat stove.

When removing the pot, the stove stuck to the bottom of the pot. When the water boils you have a natural tendency to remove the pot. Some alcohol is still in the stove and sometimes the stove will release from the pot and fall to the ground with flames spreading far and wide.

The boiling alcohol causes a seal to occur between pot and rim of stove.

Zelph, received my Super Stoves last week. Took one on a trip this past holiday weekend thru the Grayson Highlands Mt Rogers area. Could not be more satisfied, stove performed wonderful. We averaged a coffee in the morning and hot meals at dinner. Thanks for the great little stove!

Odd Man Out
07-07-2014, 10:19
I had some thoughts the last 2 days after reading the comments in this thread on what I didn't like about the fancey feast SuperCat stove.

When removing the pot, the stove stuck to the bottom of the pot. When the water boils you have a natural tendency to remove the pot. Some alcohol is still in the stove and sometimes the stove will release from the pot and fall to the ground with flames spreading far and wide.

The boiling alcohol causes a seal to occur between pot and rim of stove.

Back when I was experimenting with Supercat stoves, I found that having a small gap between the stove and the pot will increase the power of the stove. This can be accomplished by having a pot stand. This also helps make the pot more stable, but for some they like not having to use a separate pot stand. You can also do this if you have a wire (like a copper wire used for home wiring with insulation stripped off) that loops through a jet over the top of the pot. Make several of these around the perimeter. I found that the increased power made it possible to get good performance with only one row of holes (sometimes called a Simmmercat stove). The extra power made it burn somewhere between a simmer cat and super cat (I always thought the super cat gave too much heat for my taste). This has another advantage in that your stove has a greater fuel capacity. Also, I never had a problem with the stove sticking to the pot, since you don't have so much contact between the pot and the stove. This also, cuts down on the dampening effect of putting a cold pot on a stove, decreasing your priming time a lot. I've moved on to other designs, but if you are interested, you can do your own experiments.

Another Kevin
07-07-2014, 10:42
Back when I was experimenting with Supercat stoves, I found that having a small gap between the stove and the pot will increase the power of the stove. This can be accomplished by having a pot stand. This also helps make the pot more stable, but for some they like not having to use a separate pot stand.

If you're using a pot stand, why on Earth would you use an open sideburner? Go with a pressurized design and get a lot more efficiency.

Odd Man Out
07-07-2014, 14:01
If you're using a pot stand, why on Earth would you use an open sideburner? Go with a pressurized design and get a lot more efficiency.

I know, but this is in response to the OP. Plus there are those who want a stove the is very easy to build, and the simmer cat fits the bill. Not everyone is into stove building.

Wil
07-07-2014, 14:18
... I found that having a small gap between the stove and the pot will increase the power of the stove ... I found that the increased power made it possible to get good performance with only one row of holes (sometimes called a Simmmercat stove)I use the Simmercat all the time, found in my experiments that a greater amount of total heat, over the length of the burn, was extracted from a given amount of fuel than with the double row. Longer to boil, but more than compensated for by the longer burn time. I typically use about 1/2 ounce per meal. I make 3/16" holes instead of 1/4".

BTW I haven't had pot stick, in over 200 meals, surprised to hear that. Priming is a pain, but I hold the pot raised over the flame immediately after lighting to use ALL the fuel. This also speeds up the priming time as it heats the stove and fuel a bit faster.

zelph
07-07-2014, 19:25
Zelph, received my Super Stoves last week. Took one on a trip this past holiday weekend thru the Grayson Highlands Mt Rogers area. Could not be more satisfied, stove performed wonderful. We averaged a coffee in the morning and hot meals at dinner. Thanks for the great little stove!

Good things come in small packages.:) Thank you kindly for the feedback.:)

Odd Man Out
07-07-2014, 21:03
I use the Simmercat all the time, found in my experiments that a greater amount of total heat, over the length of the burn, was extracted from a given amount of fuel than with the double row. Longer to boil, but more than compensated for by the longer burn time. I typically use about 1/2 ounce per meal. I make 3/16" holes instead of 1/4".

BTW I haven't had pot stick, in over 200 meals, surprised to hear that. Priming is a pain, but I hold the pot raised over the flame immediately after lighting to use ALL the fuel. This also speeds up the priming time as it heats the stove and fuel a bit faster.

Your test results see spot on. Typically, more powerful stoves are less efficient (just like cars). I found that with my tricks of suspending the pot 1 or 2 mm above the rim of the stove, you can put the pot on the stove immediately after lighting. It burns slowly, but doesn't go out, until it primes and then the jets light up. Slightly less hassle. It was pointed out that it might seem silly to have a pot stand for a stove that doesn't need one, but I should have also pointed out that I'm a bit clumsy and spilled more than one meal, so using a pot stand with a wider base was worth it in my case. I didn't have the stove sick, but I have had flare-ups when lifting the pot. As I said, I'm now using another style. Keep tinkering Wil!

Paws60
07-09-2014, 22:12
I use a Jet Boil with a 3.5 oz container. To boil two cups of water i get on average 22 uses or boils per canister. If I were to use oil for fuel I then would need 22 oz of fuel to do the same job if you figure 1 oz of oil per burn.

Leanthree
07-10-2014, 01:06
I use a Jet Boil with a 3.5 oz container. To boil two cups of water i get on average 22 uses or boils per canister. If I were to use oil for fuel I then would need 22 oz of fuel to do the same job if you figure 1 oz of oil per burn.

I think this article and graph do a good job: http://thru-hiker.com/articles/stoveweight_vs_time_14days.php

The crossover is after 14 days the canister stove becomes lighter in their experiments. Obviously each person's set-up and qty water boiled would change this a bit.

I plan on 1 fluid oz of fuel per pint of water I need to boil. Noting that ethanol weighs 0.8oz/fluid oz on a 5 days of breakfast/dinner trip (so a 6 day trip eating breakfast the first day in town and dinner the last day in town) I am looking at 8 oz of fuel plus 1 oz stove: 9 oz total. This gives me a bit of a fuel buffer as I can normally pour some back into the bottle depending on wind, temp, etc.

Compare this to a canister that has 3.5oz of fuel + 3.7oz empty canister + 3 oz stove and the alcohol start weight wins just at the start. If you do average weight per day of hiking alcohol looks even stronger:

Alcohol weight Day 1: 9 oz, Day 2: 7.4 oz, Day 3: 5.8 oz, Day 4: 4.2 oz, Day 5: 2.6 oz, Day 6: 1 oz. AVERAGE DAY: 5 oz
Canister weight (assuming 22 burns per 3.5 oz fuel or 0.16 oz/burn .32 oz/day) Day 1: 10.2 oz Day 2: 9.88 oz day 3: 9.56 oz day 4: 9.24 oz day 5: 8.92 oz, day 6: 8.6 oz. AVERAGE DAY: 9.4 oz. If you can get a partially empty canister that will run out perfectly, you can knock this down to 7.5 oz/day but it is still 50% heavier than an alcohol stove.

There are plenty of reasons to use a canister stove (larger groups, faster boil times, wildfire restrictions, etc.) but for most trip lengths for a solo hiker, alcohol is lighter.

Paws60
07-10-2014, 07:51
Thanks Leanthree nice article.
From my experience with others around the shelter during meal time. Those using fluid to boil water seem to take several more minutes then I do. I'm packed away while they are just coming to a boil. I personally enjoy the hassle free process of getting my water to boil. Yes I agree I probably can save a few ounces by going to liquid fuel. But at the end of the day hiking, all i want is an easy warm Hassel free meal. I'm just putting in my two cents on what works for me. Hope all this helps others decide, every one has different needs and wants.

OhioHiker
07-10-2014, 08:18
I use a empty Kureg K cup to measure fuel into my alcohol stove.

With a wind in calm conditions it takes about 10min to bring to a complete boil.

It burns out shortly after that. Maybe at 12-15min. 27692

jayw288
07-10-2014, 09:24
I personally enjoy the hassle free process of getting my water to boil. Yes I agree I probably can save a few ounces by going to liquid fuel. But at the end of the day hiking, all i want is an easy warm Hassel free meal.

This was my biggest problem with the alcohol stove. I'm in the camp that will add a few ounces for the ease and simplicity of a canister stove. At the end of the day, a 4-5 ounce difference in weight does not compare to the benefits I get from the canister stove in ease and cook times IMO.

Paws60
07-10-2014, 09:45
To clarify I really don't bring the water to a boil. In the past boiling water was to hut to use. So for oatmeal or any warm beverages I just bring it to a steaming point not a boiling point.

Another Kevin
07-10-2014, 11:14
Everything in its place.

For most of my clueless weekends, I'm doing fairly short miles and in no hurry. While I'm waiting for water to boil in the evening, I'm probably inflating my Therm-a-Rest, unstuffing my sleeping bag, updating my field notes, and similar things. While I'm waiting for my morning coffee, I'm packing up most of my stuff. The alcohol stove suits this laid-back style.

I use a canister when there's high fire danger, or if some reason I expect to be in a hurry at mealtimes. This doesn't happen often.

I use a naphtha stove if I might have to melt snow for water. That takes a lot of fuel, and the high energy density of naphtha is a big win.

I use a hobo stove mostly as a curiosity. These have a pretty high 'fiddle factor' even for me, and I don't like soot all over everything.

overthinker
09-17-2014, 15:32
Quick and dirty answer: 1 ounce of fuel per burn to boil 2 cups of water.

Two burns a day x number of days = ounces needed.

You can probably get by with less for the morning cuppa, since you probably don't need fully boiling water.