Optimizing my Esbit Performance and other adventures in reinventing the wheel.

[Ian]

Situation:

My project du jour. I'm trying to optimize my esbit fuel consumption and to assemble a simple, light, and efficient system to boil water and nothing else. This is going to be an ongoing project over the next few months and I'll update this thread as I go. As always, your input is appreciated.

With my current set up, I can boil 16 ozs of water and warm up another 8ozs just enough for a lousy cup of tepid coffee in the morning. Ideally, I'd like to be able to boil 32oz of 40* water with one tablet. The boiling temperature is overshooting my needs as I'm not trying to sanitize the water so in the field I only need it to reach 150*-175*F (dependent on what I'm trying to rehydrate) and my cozy will be able to sustain that temperature with < 10* drop over 10 minutes. At a minimum, if the 32oz with one tablet is undoable, I'd at least like to enjoy a relatively hot cup of coffee in the morning setting an alternative goal of 24ozs on one tablet.

Mission:
My tentative plan is to acquire or MYOG the few systems I'm aware of who specialize in optimizing the Esbit fuel consumption (Flat Cat & Caldera Cone.) My current system is < 6oz for SP 700ml pot, cozy, stove, ti spork, windscreen, heat shield, and ti wing. A singe Esbit tablet in its package is .5 oz. It would be pointless for me to adopt a more efficient system which would add several ozs to the basic set up.

Execution:
My ti wing is weight friendly at .5oz but the flame pattern over performs for the first few minutes and I lose precious heat. One solution is to buy a wider pot but I like how the narrow pot fits in my pack so I'm trying to make this one work. I'll eventually buy a wider pot to see how that affects the performance.

So I start my journey with my first failed project (don't try this one at home kids)-

The general theory was to cut the bottom out of a fancy feast can and fill the sides with holes. By eyeing it, it seemed that the distance from the tablet to the pot was similar to what it was with the tri wing. The tri wing (my current set up) with windscreen and heat shield will achieve a boil 10-10.5 minutes. The Fancy feast project was still limping along at 15 minutes with no end in sight. I was unwilling to pursue it any further as the 10 minute boil time is at the threshold of my patience in the first place.

This was the worst of all worlds as the fuel was nearly expired at 15 minutes. This project would not work for simmering either. I found an old thread where Craig W. used a fancy feast can and cut larger holes into the side. I'll try that tomorrow and see how it goes.

So here's my failed project in all its glory:

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To be continued….

[Bob Gross]

You started off saying that you were trying to optimize Esbit fuel consumption, and then you varied away from that later on (about time). Also, I guess you know that you are trying to exceed the specs on Esbit.

Why are you trying to use the cat food can? I think that you have cut down the air flow too much, and the windscreen cuts it down even more. For example, look at the wing stove. It needs no limits on air flow. The cat food can is fine if you are burning alcohol.

I've been using a wing stove to hold the Esbit cube, and I use a simple aluminum foil windscreen. The cook pot is the Snow Peak titanium bowl which has a volume of 20 ounces, but I normally boil with either 8 or 16 ounces of water in it. If I am boiling 16 ounces, then I use a whole Esbit cube. If I am boiling only 8 ounces, then I start with a whole Esbit cube and blow it out when the water has boiled. That leaves about a half cube left warm for later use.

Additionally, the titanium bowl has a stainless steel wire bail and a lid.

–B.G.–

[Dale Wambaugh]

I've used the wing stove with a 450ml mug and that works okay, but the distance is not optimal. Check the height on the original folding stove and better yet, the spacing on the Ultralight Outfitters Beercan Esbit Stove. Something a littl taller than the wing stove will be more efficient.

You can use a Caldera Cone with Esbit too. They make the Graham Cracker holder for the Esbit fuel, which covers two sides of the tablet to control the surface area. The theory is that the tablet initially puts out more heat than the pot can absorb if all the surfaces are burning.

Go to http://www.backpackinglight.com/cgi-bin/backpackinglight/xdpy/forum_thread/59489/index.html?skip_to_post=510471#510471 and scroll down a ways. There is good info on Esbit burners there. They state the best distance is 1.5" to 1.75" and a good windscreen is mandatoy.

The Zen stove website has a good page on solid fuel stoves and shows some MYOG designs:
http://zenstoves.net/SolidFuelBurner.htm

[Ian]

Good morning Gents,

I'm glad you both weighed in as I've read several of your collective threads and comments on this very topic in the archives.

Bob,

I agree that the air flow restriction was a fatal flaw of the cat food design. My hope was that this design would create a more efficient flame pattern but it just handicapped the fuel. The fancy feast stove is .2 oz a $.50. The ti wing is .5oz and $14. If an acceptable design can be created which performs in the neighborhood of the ti wing, then the person ends up with a stove that saves weight and money. Maybe unachievable but at .$50 a can plus the cost of esbit I'll give it a couple tries.

Part of optimizing my Esbit performance is geared towards boiling the most water per oz. Here's an extreme example:
Kit A weighs 3 oz but will only boil 16oz of water per tablet. Kit B weighs 16oz but will boil 32 oz of water per tablet. In my mind, Kit A is the winner since I would need to boil 6.5 liters of water (13 oz of Esbit Fuel) to catch up with the base weight of Kit B.

I am buying the bowl and I have a couple ideas for it. One is a two bowl system where one will be cut in a 1/3 to half and used as the platform for boiling water. I like the idea that they would nest together when in storage. I want to wait until I buy a couple other integrated systems and make more observations about how airflow plays into the fuel's performance.

Dale,

I've read many of your threads and comments on this topic as well and greatly appreciate you wealth of knowledge on this topic. I'm definitely going to buy the kits you mentioned to analyze and compare them from a weight to performance perspective. I've been a naysayer of beer pot kits but at some point I'll have to give them a try as well.

Final note. I just realized this morning that my original title is a spin on Hikin' Jims Adventure in Stoving. That was not my intention.

[Dale Wambaugh]

The Ikea stainless steel utensil holder with a couple Ti tent stakes makes a good Esbit pitaform. I made a clone of the Gram Cracker using scraps from another Ikea holder. You can cover the windward side with some foil if it needs more help. You can adjust the spacing by moving the stakes to another set of holes.

Another way to do Esbit is with an aluminum flashing windscreen/pot stand using stakes. A paper punch can make the holes. It works best if the windscreen can roll up and fit in the pot. A Gram Cracker or MYOG clone and some foil on the bottom will finish it.

[Jon Fong / Flat Cat Gear]

To get ideas, take a look at Four Dog Stoves. He released a video recently that says that their stoves can boil 4 cup using a single Esbit in 5 minutes.

http://www.youtube.com/watch?v=wO-92xtyvl8&feature=share&list=UU2y8-HLT8IgDZEF9_Lr3eJg

The best that I have every been able to do was to bring 4 cups of 70 F up to 185 F. I have read of people here on backpackinglight who have been able to boil 4 cups using Esbit. Good luck on your adventure – Jon

[Ian]

I look forward to sending you a check. I've been eyeing your kits for a while.

[Nick Larsen]

I'd have to dig up the thread where I listed all the info, but I think my modified caldera cone system weighs 2.5 or 3oz total, and brings 16 oz to a boil with just over half a tab. Easily get 3 boils on 2 tabs. Might be able to get it hot enough to cook your food on just 1/2 tab, but I haven't tried it yet.

ETA: Found it. 2.9oz and 4 boils with 3 tabs… Read through this thread, at least 2 other people listed systems with similar weights.

http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=61204

[Ian]

As Bob previously mentioned, Esbit only advertises that a single .5oz tablet will boil 16oz of water. I've found that even with my unsophisticated kit, I can achieve a boil with some fuel left over. What I'm trying to do is exceed reasonable expectations. I also realize that my water doesn't need to reach boiling temperatures to rehydrate my food or fix coffee.

So here is what I'm working with at the moment. My kit consists of a Snowpeak 700 (handles, lid, and hardware removed), a pot cozy, Esbit ti wing, heat/residue shield, aluminum windscreen, mini bic, foil lid, and a small green scrubby. Total weight is 5.1 oz. I can boil 16 oz of 40* water in about 10.5-12.5 minutes; there is normally some fuel left over but not enough to warm 8oz of water for coffee.

Photo of the complete kit

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Didn't come out great in the photo but the flames are crawling up the sides of the pot. I could buy a wider pot and make better use of the flame pattern:

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Remaining fuel doesn't register on my scale:

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Normal complaint about Esbit is the residue left on the pot. As I store my pot in my cozy, it doesn't come in contact with any of my gear when I'm backpacking. This picture is typical for ~ three boils. It washes off with plain water easy enough and looks like new.

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While the Snowpeak 700 is a great ti pot, it's more than I need and I regret not buying the 600. Every ounce saved equates to two extra boils. Fortunately I have kids who can use an upgraded cook kit so I can buy the 600 relatively guilt free. I'm also going to buy the Snowpeak titanium bowl to see how it performs.

[Ian]

I've been following this thread with great interest. Daniel used a Sol Ti pot to see how well it would work with Esbit. At this time, his kit weighs 16ozs which is nearly 11ozs heavier than my current system. While a very interesting use of this pot, the weight penalty equates to 22 Esbit tablets or 11 liters of water with my inefficient system.

While not for me, kudos to Daniel for thinking outside of the box and sharing his experience with this kit. I look forward to see the future refinements of this system.

http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=74676&startat=20

[Ian]

This is a disappointing kit. Removing the lid and mesh stuff sack will save 1.5 oz; I've decided not to use it for backpacking so I haven't tried to remove the handles. If I were to use this kit, it would include the integrated stand/windscreen, pot with handles, lighter, green scrubby, cozy, and foil lid. With this setup, it weighs in at 7.7oz or 1.6 ozs heavier than my current kit.

Not only is it heavier but the fuel efficiency is worse. Trying to boil 16oz of 40* water, it will use the entire Esbit tablet and barely reach boiling temperature before the fuel is gone. Add anything resembling a breeze to the equation and there have been times where it failed to boil the water.

I like that the pot has graduated marking and it is very stable. The down side is that when in storage, Esbit residue will contaminate the cook pot.

Due to the lack of performance, extra weight and issues with Esbit residue contaminating the pot when in storage, this cook kit has been retired to my truck and I do not recommend it for backpacking.

Picture of the kit. For weight purposes, I used the same cozy from my Snowpeak 700 cook kit:

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>13 minutes later and failed to reach a boil. In all fairness, the water is plenty hot to rehydrate a meal or for coffee:

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