Esbit burner testing

Eric is funny 

Look at the size difference in the 2 large esbit stoves compared to the original that is sitting inside the one on the right. The large ones could easily be made into nice twig burners. I like dual fuel stoves :-)

“SERIOUSNESSLY”… is there a way to chemically alter ESBIT’s compound to make more heat?

I want MORE HEAT. (And then there’s de-tuned solid rocket fuel….) (Do I smell a dead horse?)

[edited MK]

We have to forget about more heat out of esbit and concentrate on conserving what is already there. I have the ultimate set-up that boils 2 cups of water with 2 four gram esbits under ideal conditions using a Toaks 500 without handles.

IF someone comes up with a more powerful fuel, I’ll be the first to purchase it and switch from wood to the newcomer

Eric,

Just start experimenting with Calcium Carbide, preferably in your back yard.

It has power

Found this but can’t say for sure if it’s true. California might frown on it.

When carbide comes in contact with moisture, it produces acetylene gas. Acetylene acts like ethylene and accelerates the ripening process, but is inadvisable because calcium carbide has carcinogenic (cancer causing) properties.

Yeah, but please note the very bright yellow flames: there’s a LOT of soot coming off those flames. Totally wasteful of the potential, since acetylene (with enough oxygen) makes a VERY hot flame.

We used to use carbide lamps when caving, with a slow controlled drip-feed of water and a single jet. “”Trog lamps”. They relied on the yellow flame of course.

Cheers

Oh My! look what’s out there Eric…power in a tube:

http://www.historicrail.com/Big-Bang-Gun-Bangsite-Ammunition/productinfo/M902823/

This will put a smile on Eric’s face in the morning:

As a moderator, I don’t like to get involved in thread drift. When the thread is about Esbit and someone mentions an alcohol stove or makes a pun, I’m not doing anything about it. This thread is getting a bit out of hand. I’d like to redirect the discussion away from women and back to Esbit please.

From the moderation page

“10. Do not deviate from the primary topic of the forum thread.“

My apologies.

So I’ve been experimenting with a new cone from TD using a tiny piece of Ti Foil bent into a U around two piece of 4g Esbit stacked on top of each other. This cone relies on a silicone band which allows me to adjust the Esbit to pot bottom distance. I’m wondering if you Esbit gurus can weigh in on any of the following:

1. Is there an optimum distance between fuel and pot when using Esbit or does it depend on the size of the pot and the stove?
2. Does the quantity/composition of the soot indicate anything about the optimization?

I know I need to just keep experimenting and logging my results but any wisdom that would help me get there would be appreciated.

Just in case it’s reevant, this is a small, narrow mug (MLD 475).

I would have to yield to Dan’s expertise on that magical distance.

The only thing I would note is that when I use 2 x 4 g tabs, I place them side-by-side, and normally in an Esbitmiser tray (without the lid). That allows me to warm a precooked stewy meal quite nicely, unless conditions are too windy.  But it would depend on your objective. I don’t normally go to a full boil.

If you are getting much soot, that suggests less than optimized combustion, but again Dan has the expertise – I just work here. I usually use a wet wipe to clean the pot base, after cleaning the spoon, pot lid, folding mug, and pot interior (for coffee, not stew); there shouldn’t be much (external) residue, so for coffee, I don’t need to further wash the gear between uses.

Is there an optimum distance between fuel and pot when using Esbit or does it depend on the size of the pot and the stove?

All dependent on the stove design and pot windscreen configuration

Does the quantity/composition of the soot indicate anything about the optimization?

IMO, if you produce a flat black, dry soot then it is not burning efficiently.  If you produce a brown, waxy looking soot that you can wipe a majority off with a paper towel, it’s burning pretty clean.  My 2 cents.

This is an old but interesting video.  They demonstrate an ESBIT stove that is virtually soot free.  The geometry does not lend itself to backpacking, but interesting never the less.  My 2 cents.

Top of esbit to bottom of pot should be 1-3/4″. More would be better but we have a tendency to want to keep the distance down to facilitate pot supports fitting inside of short/narrow pots.

Jon’s video shows clearly the farther away, the cleaner.

So we know the height from top of tab to bottom of pot for optimum heat transfer.

This setup seems to totally throw that out just in the name of getting “no soot”. No thanks, I’ll take faster boil/cook times with soot.

Long day at work today. Just reading your comments now. Thank you for sharing them.

“IMO, if you produce a flat black, dry soot then it is not burning efficiently.”

I am getting a very fine, black soot. What does “not burning efficiently” mean? Am I not fully combusting the Esbit fuel? Not enough oxygen?

Robert, I’ll try the tablets side by side. I assumed stacking them made more sense.

My goal is light weight. I want to burn fuel very efficiently. I don’t care about cooking time.

So I’ve been experimenting with a new cone from TD using a tiny piece of Ti Foil bent into a U around two piece of 4g Esbit stacked on top of each other. This cone relies on a silicone band which allows me to adjust the Esbit to pot bottom distance. I’m wondering if you Esbit gurus can weigh in on any of the following:

Adjust the distance to pot with silicone band so the top of cube is 1-3/4″ to the pot bottom. Bend your aluminum foil tray to act the same as a BGET.  Start with that. If you still get soot, increase distance to 2-1/4″.

If you continue to have soot, contact Trail Designs and see what they suggest. Air intake has to be sufficient to burn clean also. We’re into the Winter Solstice which may have an adverse affect on the efficiency 

Side-by-side for slow cooking (which I regard as preferable); stacked for more rapid and intense burn.

Unfortunately, it is not possible to do the subject fair justice, without devolving into the phenomenological dimensions of the flame, and of fire, witness Bachelard.

As a mathematical aside, the number of side-to-side combinations and permutations of two identical cuboid Esbit tabs is rather (dramatically) higher than I anticipated, though admittedly some configurations are constrained by gravity and practicality.

Say that with an Esbititish accent   “It is better to live in a state of impermanence than in one of finality.”

What does “not burning efficiently” mean? Am I not fully combusting the Esbit fuel? Not enough oxygen?
Exactly.
The soot is carbon from the Esbit tablets. By not burning it fully, you are wasting fuel weight and not getting all the energy available in the fuel.

Cheers

Robert, I’m quite surprised to hear that side by side burns slower. I assumed that the greater surface area means they would burn extremely quickly.

Dan, I have a couple of your BGET trays. I’ll switch over to those if the 4g tabs fit side by side (I think they do?). If not, I’m pretty sure I have an Esbitimizer that Robert mentions from you in my box of stove stuff. Or I’ll make a tray. Also, thanks for the distance recommendations.

Roger, thanks for confirming/elaborating. Air intake will be easy to experiment with, I can scratch a couple grooves into the ground and see if that gets rid of the soot.

I am led to wonder: has anyone ever tried putting a ‘chimney’ around an Esbit tray (air gap at the bottom of course)? I have NO idea whether this would improve the mixing of Esbit fumes and air for better combustion – or just make it worse.

Cheers

This is close to a chimney