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oops56
2006-07-17, 02:34
Now this is easy to do a 1 in. hole down the middle 3/4 way one in from side i used a piece of fire stater to get it going 4 nails for pot stand not the best in the world but it works :dancing2:
http://i33.photobucket.com/albums/d52/oops62/th_wood1.jpg (http://i33.photobucket.com/albums/d52/oops62/wood1.jpg)

SGT Rock
2006-07-18, 06:26
Wood stoves burn wood, they are not supposed to be made from wood :D

KLeth
2006-07-18, 07:05
I know that principle as a "Finnish Stove". It's an ancient way of cooking that is still in use in the northern part of the world.
It can be made out of a log bu sawing in it and it can be done by drilling it in.
The nails are really not needed but is a nice touch. :biggrin:

Hog On Ice
2006-07-18, 10:43
I remember a similar technique using a coffee can packed with saw dust except for a central hole.

Take-a-knee
2006-07-18, 18:33
On a different tack, another improvised method of cooking is to use a coffee can for an oven. Find a flat rock and place your freshly (creek?) washed cornish game hen, still frozen, inside the coffee can. Invert the coffee can on top of the rock and pile as much pinestraw on top of it as you can, at least waist high, and light it. When it all burns down retrieve your "oven roasted" hen. A still-warm freshly killed grouse or other small game would take less cooking time. You'll have to experiment on your own.

Lanthar
2006-07-19, 14:49
Wood Stove: :confused: Wow...

Pine Straw / Coffee Can 'Oven': That's actually one cool idea that I will NOT be sharing with the scout troop... Good god, I don't even want to think what would happen if some of them lit off a pile of pine straw...

Take-a-knee
2006-07-19, 18:10
Actually, it doesn't burn that fast, at least not here in the southeast with our humidity. When you heap up the pine straw you clear the nearby area of most anything that will burn anyway. This is taught in the army's SERE course.

Lanthar
2006-07-20, 19:09
Actually, it doesn't burn that fast, at least not here in the southeast with our humidity. When you heap up the pine straw you [SHOULD] clear the nearby area of most anything that will burn anyway. This is taught in the army's SERE course.

:biggrin: I modified your statement slightly to reflect my concern with some of our boys...

Then again, I was talking with our committe chair about showing them the 'chlorine pool shock in brake fluid' trick... so I may be somewhat incosistent in my views... :damnmate:

ripvanarkie
2006-07-21, 00:14
'chlorine pool shock in brake fluid' trick...

I am not familiar with this trick, what happens?
Later,
Rip

Iceman
2006-07-21, 00:59
White smoke, followed by flame. Try a google search.

incognito
2006-07-21, 22:40
Nice going oops, put some potassium nitrate in there, makes it a little hotter, or a little magnesium to make it into a lantern, love those dual purpose stoves

Hog On Ice
2006-07-22, 13:15
speaking of cheap wood burning stoves I got inspired to make a hobo stove today

my inspiration was observing that a Heineken pot fits just about perfectly sitting on top of an empty Nido can I had laying around - the pot sits in the opening of the can up to the first major ridge around the Heineken can - great way to support the pot

then I judged the weight of the Nido can against my alcohol fuel and bottle and found it is lighter than the fuel bottle plus a typical amount of alcohol

lastly I looked at a short piece of pipe I sometimes use for gathering water and realized it would make a good blow pipe for the wood burner

anyways I punched and nibbled a hole in the side at the bottom and another in the opposite side at the top and put in a hardware cloth support just above the hole in the side at the bottom

now all that is left is to fine tune the holes - this should take me a few weeks of playing around

sigh and I thought I had beaten the addiction

Lanthar
2006-07-24, 16:48
White smoke, followed by flame. Try a google search.

As long as you don't put too much shock in at once (*fondly reminisces about the look of exasperation / horror on my mothers face as my father and I leap off the back patio in order to dodge a 6-foot fireball...*)

HOI, this Nido?
http://us.st11.yimg.com/us.st.yimg.com/I/asianmerchant_1908_26736889

Hog On Ice
2006-07-24, 17:30
Lanthar - yes that is the stuff the opening in the top is just the right size to hold a Heineken 24 ounce can

So far my experiments with the hobo stove have produced a serious accumulation of creosote - obviously I need to get more air into and out of the stove.

incognito
2006-07-24, 19:16
HOI ------ Glad to see you back in the stove build mode. Sounds like an interesting project.

Give it more oxygen than it needs!!!!!!!!

Vent it big time!!!!!!

JAK
2006-07-25, 03:49
A hobo stove with one of those "wood stoves" just fitting inside of it would be rather neat. Not all that efficient weight wise since dry wood is only 8000 btu/lb, but it would get better, and lighter, as it chars with use. It would be super-insulated at first. You could also add fuel as you go to conserve the stove. A 4"x10" stove would fit in a nalgene water bottle holder. If you used a dense hardwood like oak it would weigh about 3 pounds and might last a week or two. You would need a way to snuff it out. An air tight lid and side plug would work. If you start with only a 1" diameter hole you could use alcohol for the first few burns to get enough heat. Once it is charred you might be able to use a little bit of canola oil to conserve the wood. The efficiency of the stove migh make up for some of the extra wieght. If you normally get by on 8oz of alcohol for a short trip then perhaps you might get just as far on a small 12oz wood stove. 3"dia x 6" high maybe.

Perhaps the peace pipe was the original microlight hiking stove. :)

Lanthar
2006-07-25, 13:29
Lanthar - yes that is the stuff the opening in the top is just the right size to hold a Heineken 24 ounce can

So far my experiments with the hobo stove have produced a serious accumulation of creosote - obviously I need to get more air into and out of the stove.


HOI ------ Glad to see you back in the stove build mode. Sounds like an interesting project.

Give it more oxygen than it needs!!!!!!!!

Vent it big time!!!!!!
HOI, Unless you go true-gassifier-type (debatable in it's benefit as I believe you're looking for light-weight simplicity) you're never going to get ALL of the creosote to dissapear (though you can get a good bit with really good venting as incog said). What I would consider doing is venting it like: J. Falk's Wood Burning Trail Stove (http://site283.webhost4life.com/afmservices/trailgear/falk-wood-stove.htm), it seems to me that this would be a great way to set it up with a Henie-Pot.

I found my own can at home that 'mates' to the bottom of the henie-pot (I'm not sure what it was in a previous life)... the only downside I see is that the pot and stove won't 'nest' for packing (not that it really matters) so what I may do is look at a mating one and one large enough for the henie pot to nest in and punch a couple holes as a stand (using tent stakes) when I want to use the wood burning stove... (If I get some time this week I may whip that up and post some pics...)

JAK
2006-07-25, 14:37
HOI, Unless you go true-gassifier-type (debatable in it's benefit as I believe you're looking for light-weight simplicity) you're never going to get ALL of the creosote to dissapear (though you can get a good bit with really good venting as incog said). What I would consider doing is venting it like: J. Falk's Wood Burning Trail Stove (http://site283.webhost4life.com/afmservices/trailgear/falk-wood-stove.htm), it seems to me that this would be a great way to set it up with a Henie-Pot.

I found my own can at home that 'mates' to the bottom of the henie-pot (I'm not sure what it was in a previous life)... the only downside I see is that the pot and stove won't 'nest' for packing (not that it really matters) so what I may do is look at a mating one and one large enough for the henie pot to nest in and punch a couple holes as a stand (using tent stakes) when I want to use the wood burning stove... (If I get some time this week I may whip that up and post some pics...)I use a Kelly Kettle and a Swiss Canteen Stove. Both create a lot of creosote and soot, but with the Kelly Kettle it is on the inside and is a lot less messy. Also no pots to clean. With the Swiss Canteen Stove it is on the outside of the canteen, and it pretty much ends up everywhere, which is OK if you don't have much gear and you rolling around in the sticks and snow for a week, but not so great for a day hike. I think this stove was originally intended for use with a small gas burner. I might get a second one to keep clean and only use with a small alcohol stove. I prefer the Kelly Kettle usually, but the Swiss Canteen has some advantages in winter because you can melt snow with it and cook stuff directly, and melt the water if it freezes in the canteen. More compact for cross country skiing also.

Back to hobo stoves. I don't think you can ever stop the smoke on startup, but once the Kelly Kettle is burning well the flame shooting out the top is pretty clean. If course as soon as you put a pot of cold water in that flame you will get smoke and creosote. I think with wood you always have a blackened pot, but here are some ideas to reduce it for somewhat higher efficiency and less mess.

1. You need high temperature for the initial combustion, so minimize mass in that area and provide some insulation and baffles while still allowing sufficient air flow, but not excessive air flow, with either force or induced draft.
2. You need a tall chimney to induce a good draft. The Kelly Kettle works great at about 10". It would be difficult to balance the pot and wind screen on top of this however. This means the stove and pot stand must either be heavier, or hung from a branch, or a force draft must be provided.
3. Ceramic insulation allows higher temperatures but adds weight and thermal mass. Baffles and air spaces and perhaps a bit of fiberglass insulation in the air spaces should be enough for a light stove. Sand or dry earth could be used on site. A stove that is designed to be half buried might work well and also solve the height and weight problem, as long as their is dry earth or sand to dig in.
4. Aluminum will melt and burn in contact with flame unless it contains water, but if it contains water you will always get soot, even if the water is hot. Thin steel should be used for the primary and secondary combustion chambers. Thin aluminum could be used for the rest of the stove and wind screens and pots.
5. The secondary chamber could bring in some additional air, but really just provides time and space for volatile gases to finish burning before the hot gas comes in contact with the pot full of water.
6. Another strategy to reduce soot is too allow most of the volatile gases to burn off first before placing the pot. You are essentially making charcoal first. Charcoal will burn at higher temperatures with less air, and you should avoid soot if there is sufficient air and you allow combustion to complete before the gases come in contact with the pot. Once you are burning char the secondary combustion chamber can be alot smaller. This requires more time and fuel, but invloves less soot and potentially a more compact design, and you can save some charcoal for the next meal.
7. Another strategy is indirect heating, where the hot gases do not come in direct contact with the pot. Basically a pot within a pot, with the outer pot a permament part of the stove. In this case the outer pot should be steel, but the real pot can be aluminum. There should be good metal to metal contact to maximize heat transfer. There can be a problem with thermal expansion getting the pot out if the stove cools while the pot is still hot.

Without making it too complicated, I think a simple design would be a tall hobbo stove with a steel can drops about half way down into it that is just big enough that your aluminum beer can pot has a loose fit inside of it. Water between the cans might increase heat transfer. You would need at least one hole on the bottom to feed sticks and allow air in and to light it. The space between the stove and the outer pot might be enough of a chimney. You could keep it that simple, or add some complexity here or there. For example, some baffles and or insulation, underneath for example, might allow higher combustion temperatures, but add weight and complexity and space. If you can plus the hole on the bottom and put an airtight lid on top with a pinhole vent you can carry unburned charcoal and also use the stove to make charcoal for better combustion and lighter fuel. This would be a good trick if you were to have a meal or two above the tree-line, or in an area of high traffic where not wood fuel is available.

JAK
2006-07-25, 15:09
Compact wood stove using above idea. The inner pot could be a beer can, with or without top removed. If you add some water to outer pot you might even reheat a PET bottle directly. However, this might increase the likelyhood of growing man breasts or a third nipple. :questionm

Parts:
Inner Pot: Standard Aluminum Beer Can: 2.75"D x 4.75"H
Outer Pot: No.300 Standard Steel Can: 3.00"D x 4.44"H
Stove Pot: No.400 Cylinder Steel Can: 4.25"D x 7.00"H

This gives you about 2.5" on the bottom for a combustion chamber.
You could support the outer pot permamently somehow.
You could feed sticks in and keep pushing them as they burn.
I have no idea what these cans look like. Is a coffee can one of them?

http://www.cancentral.com/standard.cfm

incognito
2006-07-30, 00:56
Oops, how much does it weigh? (just kidding)

oops56
2006-07-30, 01:27
Now my stove can do two things at once
http://i33.photobucket.com/albums/d52/oops62/th_jiff2.jpg (http://i33.photobucket.com/albums/d52/oops62/jiff2.jpg)

JAK
2006-07-30, 11:27
Now my stove can do two things at once
http://i33.photobucket.com/albums/d52/oops62/th_jiff2.jpg (http://i33.photobucket.com/albums/d52/oops62/jiff2.jpg)Way cool.
I was thinking you could stack some angel food pans for melting snow also.

Love the ashtray on the wall by the way.

oops56
2006-07-30, 12:16
where i use to work i was in charge to put them up in the smoking area cause i smoke somehow one was left over

JAK
2006-07-30, 14:33
where i use to work i was in charge to put them up in the smoking area cause i smoke somehow one was left overFunny how often things seem to work out that way. :beer:

JAK
2006-08-07, 21:36
SO HERE IS MY LATEST DESIGN CONCEPT,
INSPIRED BY SIMPLE WOOD STOVE.

#1 4.0" diameter roll of toilet paper.
#2 Seal in one layer of muffler tape on top, bottom, outside, inside.
#3 1.5" diameter hole into side, centered 1.0" from bottom, also sealed with muffler tape.
#4 Drill a few holes into the toilet paper from the inside, near the bottom.
#5 Extend the sides up to twice the height, with a muffler tape, toilet paper, muffler tape sandwhich, such that the walls are about 1/4" thick.

Fire the stove up really for awhile by burning wood sticks in from the side without water on top. The toilet paper should gasify and char and vent out the bottom of the combustion chamber. The toilet paper in the top windscreen should be OK, but you might need a few pinholes just in case. The glue in the muffler tape should keep it all together. I am not sure how hot the muffler tape can get. If it burns through from the inside it could be resealed with another tube of muffler tape, or a thin steel tube.

To use the stove set pot on top, inside the insulated windscreen. The pot needs to be raised above the top of the toilet paper by some means by about 1/4", the same gap as on the side, perhaps a bit more for a smooth transition. A spark arrestor could be incorporated also. The area of the gap on the sides should be the same as the center of the toilet roll, about 1 sq inch per 250ml of water. This works out to about a 1/4" gap on pot sides and a 1.75" diameter chimney in the toilet paper roll for a 24oz pot. A 3"diameter x 6"tall pot would be ideal. A 3-7/16" diameter Heinekin Pot could be used by using a slightly larger diameter toilet paper roll, or my not insulating the top windscreen.

Well I have talked long enough. Time to build something. :damnmate:
Give me another week, as I am way behind on my report, totally unrelated.

oops56
2006-08-07, 22:50
You know Jak i must be brain dead i red this 4 5 6 7 times cant seam to get it in my head a picture or two would help

JAK
2006-08-07, 23:37
I'm hoping me actually building it might help also. :)

p.s. I won't be able to get at it for a couple of days.

p.p.s. The idea is that the insulated chimney down below provides higher combustion temperatures and space and time for complete combustion before hitting the cold pot. The vertical height of the chimney also provides enough draft to squeeze the hot gases past the sides of the cold pot. The gap on the sides is narrow enough to cause turbulent flow for better heat transfer, but not too narrow to cause incomplete combustion due to air starvation. The narrow chimney allows more kinetic energy in the combustion zone for better combustion and more momentum for a more effective draft. The insulated windscreen ensures that more heat is transfered into the pot that out the sides. By only pushing the sticks in as they burn combustion is controled to be more constant, and the combustion chamber can be smaller and hotter. With a small wood stove for camping the idea is not so much to increase efficiency to save fuel, but primarily to reduce smoke and soot. A woodstive needs to be somewhat taller and heavier than an alcohol stove because of this extra height in the bottom half, but the top half is essentially the same.