Darren Bos wrote:

But, for those with less experience, maybe it is worth pointing out the danger of CO poisoning?

David,

I see your point with the missing rail, the steel body and the low power. Still, I had a two-burner Optimus paraffin stove in Malena, with a steel body, and that held very well.

Actually, I was thinking of giving the Salsa another job (in addition to cooking): To heat the cabin. If it turns out to burn without making smoke, smell or soot, that could produce cheaper kilo-Watt-hours than my present butane-cartridge heater. Combined with a 12V fan, it would turn into a Poor Man’s Webasto.

The butane heater was supposed to be very safe in use and turn itself off if tipped over, or if the O₂ dropped below 16%. However, one day I returned to the boat, there was a suspect smell of gas. It turned out that the almost full cartridge had leaked empty during the last twelve hours. I opened up all hatches and cabin sole and left the place for an hour.

Therefore, I will rather deal with alcohol. I do any filling of canisters etc. in the self-draining cockpit. Any spilling can be washed away with water.

Arne

The hpv Salsa blue flame alcohol stove

If a blue-flame alcohol stove still is on my mind in the future, I might order the single-burner Salsa, or twin burner Mambo, from the German manufacturer, HPV . It seems that Germany, including DDR, has had a long tradition of making these stoves, and the Salsa and Mambo appears to be of quite high quality. However, its output is only 1.0 kW (burning 0.20 l/h), so an efficient pot could be welcome. See the description of it by this user. To me, it looks like the Salsa works much like the Maxie stove, but possibly, the burner lasts longer. Maybe a raised tank (with its own stop valve) would boost its performance a little, and make it less vulnerable to the boat’s heel angle? Wasn’t that what you did to your Maxie stove, David?

Personally, I could think of having two different single-burner stoves side by side each other, in Ingeborg, one hpv-Salsa and one Origo 1500

Arne

Darren, thanks for an interesting input.

Today I had a final go with the Origo ‘upgrade’. I had some (3/16”?) copper pipe laying around, so I bent it to fit into the central fire tube of the burner. Two rows of 1mm holes were drilled, see photo below, left. The idea was much the same as yours, to inject air into that central flame.

Boil tests showed about 4:30min to boil (dry kettle), about the same as without the booster, yesterday. Frankly, the aquarium pump was not strong enough to make much difference. On the photo below, right, one can see the flame with the booster off. As can be seen, the central flame is yellow while it turns blue when spreading out. Today was very calm, and this helps to get this nice flame  -  the Origo doesn’t like too much draft.

The kettle, made to fit electric stoves, actually appears to make good use of the alcohol burner. The handle does not get very hot. As for smell, I always cook with the main hatch open. The galleys of all my boats have been in this position.

I now have the option to keep on using the Origo, or to reinstall my (kerosene) Optimus stove from Johanna. For my simple use, I guess I will stick with the Origo. It is good enough and safer and simpler in use than any other stove I have had or used.

Until I find a stronger, but still cheap air pump, I’ll drop this project. What I have gained, apart from some experience, is a weird collection of funny-looking bent pipes and twisted copper and tin plates. Maybe I should frame them and hang them up one the wall. A temporary title could be

“Twisted products of a twisted mind”

Any better suggestions?

Cheers,
Arne

.. yes, the kettle is also important..

David,

I agree with you with respect to soot and CO. As can be seen below, my kettle has been blackened quite much. However, it doesn’t seem to build up much soot on it. I wonder if it has to do with my use of it. After other cooking, I generally fill the kettle up for heating dish-washing water. This I do with the burner on the lowest setting with all-blue flame. Maybe this helps to burn the kettle clean.

I can think of two more tests of the booster before I drop it: One is to use the shown ring of copper, and then raise the kettle about 10mm to improve airflow. The other is to use a thin copper pipe and bend it to a J-shape and fit it down the primary flame tube of the stove. With a number of 1mm holes in that pipe, hopefully that will add enough oxygen. That solution would not hinder normal airflow under the kettle.

Quite another thing is the shape of the kettle. Heating any normal kettle or casserole over an open flame is very inefficient.

The specific energy capacity of water is 4.183kJ/(kg K). In plain English that means that that it takes 4.183 seconds to heat a litre (= 1 kg) of water one degree (Celsius or Kelvin) if one Kilowatt heat power is added.

To heat 0.5 litre of water from 15°C to 100°C, one should therefore need an energy of...

0.5kg x 85°K x 4.183kWs/kgK =177.8kWs =177.8kilo-Joule.

If we add 2000 Watt (2kW) heat power right into the water with no loss, it will take just..

t= 177.8kJ/2kW=88.9seconds to bring it to boil.

Now, the makers of Origo 3000 claim that each burner produces 2kW.

Since I needed 4:30min. =270secons to heat that water,...

then the efficiency can only have been 88.9s / 270s = 0.33, or 33%. In other words; two thirds of the energy is lost!

Increasing the temperature on the flame will improve the efficiency, but my hunch is that that there is a lot more to gain from improving the kettle than from modifying the stove. Thinking of how the boilers of steam locomotives are built, should give a hint...

Arne

PS: Just to compare, now I tested my domestic 2kW electric water kettle. From cold, it took 118 seconds, and on the next test, with the now warm kettle, it took 93seconds to boil that 0.5 litre. That gives about 75 and 96 % efficiency...