high pressure alcohol stove

[lannyman8]

now this is just a test stove, i plan to tidy things up when i get the burning right...

this stove cost £00000 to me, its made of 4 coke cans, i did use some JB weld but did not wait long enough for it to dry, so when i tested it, it caught fire and burned off....

ok 2 coke can bottoms pressed together formes the pressure caseing, then put 1 thumb tack hole in the very centre.

take another coke can and cut 3/4 to 4/5 from the top, again as in making coke can stove. cut a burn hole and air vents in the side of the bottom but after you have very carefull pushed the seal pressure part inside so it sits in the middle.

now, with the last can cut the centre from the bace but leave as much of the lip as possible, punch or drill vent holes around the rim, now push onto the other parts, be careful not to split the can like i did....

quite basic really, the pic's should help...
























when i first filled the stove it was drip fed so i had to make more holes to relive the pressure for it to trickle in, the next stove should be more fuel effective with 1 pin hole, and i will try it with a candle on the bace instead of meths.

it was very windey outside and cold, but even with a bean tin wind shield it was badly effected by the wind, the next copper coil type should fare better though...

more on these to come (when i eventuly get some time to make them )...

thanks for looking.

chris.

 

[greensurfingbear]

For the sake of being impartial Other aluminium drinking cans are available

On a serious note, sweet looking make. Nice work mate


Orric

 

[Johnnyboy1971]

Don't know if this will be of any help but I noticed the pepsi cans from multi packs were a little stronger and rigid.

 

[lannyman8]

Don't know if this will be of any help but I noticed the pepsi cans from multi packs were a little stronger and rigid.

oooooohhh.....

thanks dude...

 

[Elines]

Looking good and will be interested in the next version.

Not sure I understand all the details yet but as regards the filling holes could you put in more in a small group and then put a penny on top to seal it when in use - this is what is done by Benjy at

http://www.bushcraftuk.com/forum/showthread.php?t=83420

Pics have disappeared but see video at post 9

A refinement I have seen elsewhere is:

• put the part that will have the holes in over a piece of wood
• place a penny on it
• bash the penny with a hammer to squash the penny into the aluminium to make an indent in the aluminium so the penny has a better, more airtight fit

Not sure if this actually makes any difference but can't do any harm

 

[shaggystu]

....Not sure I understand all the details yet but as regards the filling holes could you put in more in a small group and then put a penny on top to seal it when in use...

i think with this set-up the only burner on the sealed (pressurised) section of the stove is the filler hole itself, so i don't think that covering it with a penny would work in this instance, i might be wrong though.

interesting little stove this one, i've had a play with a few different designs of meths pressure stoves but haven't really found one that i get on with. this design is definately gonna get tried out at some point

stuart

 

[Elines]

i think with this set-up the only burner on the sealed (pressurised) section of the stove is the filler hole itself, so i don't think that covering it with a penny would work in this instance, i might be wrong though.

interesting little stove this one, i've had a play with a few different designs of meths pressure stoves but haven't really found one that i get on with. this design is definately gonna get tried out at some point

stuart

You are probably right Stu - I was looking at the three top pics and there seemed to be holes at about 12 oclock - 2 o'clock but these may be just marks/blemishes as the holes don't continue round the inside of the can.

And there I was thinking that the main thing I didn't understand was "but after you have very carefull pushed the seal pressure part inside so it sits in the middle" ..... so will be very interested in the fuller guidance

 

[shaggystu]

.....I was looking at the three top pics and there seemed to be holes at about 12 oclock - 2 o'clock but these may be just marks/blemishes as the holes don't continue round the inside of the can.....

i came to the same conclusion, some kind of blemish on the can, we could well both be wrong though. it's a bit tricky to tell what's going on from the pictures, but then meths burners are really tricky to photograph well (the photo's do photoshop quite nicely though, the psychodelic mutant space squid in my avatar is actually a photoshopped "whitebox" stove).

all this talk of stoves has me edging closer and closer to my box of empty cans and further away from what i'm supposed to be doing, i'm just hoping that i've not got much meths left or i'll be at it all day and then there will be trouble when she gets home

stuart

 

[Martyn]

Let me see if I understand this right Chris? You basically have 2 stoves, a sealed one with a couple of small burner jets in the middle, sitting on top of an open one, which at the moment you have filled with meths. The bottom one heats up the top one and pressurises it, causing a fierce flame?

I've tried similar semi-pressurised stoves (the photon) and they work well, but my gut reaction to your design is that you will have problems keeping the top flame lit without some kind of pilot light and that it will be very fuel hungry. My guess is the big meths flame on the bottom part, is keeping the meths flame on the top part lit. If you use a candle on the bottom part to economise on fuel, what will keep the top part lit? Might work, but you'd have to experiment with jet size, placement and number, so that it stays lit under the given pressure (heat from a candle). Nice idea, looking forward to where you take it. Could be a good winter stove if you can balance the pressure thing.

 

[mountainm]

Let me see if I understand this right Chris? You basically have 2 stoves, a sealed one with a couple of small burner jets in the middle, sitting on top of an open one, which at the moment you have filled with meths. The bottom one heats up the top one and pressurises it, causing a fierce flame?

I've tried similar semi-pressurised stoves (the photon) and they work well, but my gut reaction to your design is that you will have problems keeping the top flame lit without some kind of pilot light and that it will be very fuel hungry. My guess is the big meths flame on the bottom part, is keeping the meths flame on the top part lit. If you use a candle on the bottom part to economise on fuel, what will keep the top part lit?

I was wondering the same - using a tea light on the bottom of a normal pop can stove - then perhaps a circular wick instead of a pilot light if the pressure blows the jets out - to work in a similar principle to a fire hoop - ie. if it goes out in one area it relights itself

 

[Martyn]

I was wondering the same - using a tea light on the bottom of a normal pop can stove - then perhaps a circular wick instead of a pilot light if the pressure blows the jets out - to work in a similar principle to a fire hoop - ie. if it goes out in one area it relights itself

He might be able to do it from balancing the jet size against the pressure generated. The problem is the pressure isn't a constant. As the stove heats up, the pressure will go up. For it to work, the jet hole would have to be big enough, for the flame to stay lit even with the fuel inside rapidly boiling - being the theoretical max pressure. Problem with that is it would take a while to get to that pressure. Your wick idea might be better. Kind of like the priciple behind the SVEA 123 stove. Either that or a burner/spreader plate of some kind ...as is used in most pressure stoves. The way the pressure is regulated in the Borde bomb, is that only the fuel in the pipe loop is getting heated from the flame, so once it's hot enough to jet, it self-sustains and doesnt over pressurise. That's going to be the problem with this design I think.

 

[lannyman8]

i came to the same conclusion, some kind of blemish on the can, we could well both be wrong though. it's a bit tricky to tell what's going on from the pictures, but then meths burners are really tricky to photograph well (the photo's do photoshop quite nicely though, the psychodelic mutant space squid in my avatar is actually a photoshopped "whitebox" stove).

all this talk of stoves has me edging closer and closer to my box of empty cans and further away from what i'm supposed to be doing, i'm just hoping that i've not got much meths left or i'll be at it all day and then there will be trouble when she gets home

stuart

no your right, its a hole, well 3 in total, i had to make them because i was at work and had nothing to put the meths in with.....

 

[lannyman8]

He might be able to do it from balancing the jet size against the pressure generated. The problem is the pressure isn't a constant. As the stove heats up, the pressure will go up. For it to work, the jet hole would have to be big enough, for the flame to stay lit even with the fuel inside rapidly boiling - being the theoretical max pressure. Problem with that is it would take a while to get to that pressure. Your wick idea might be better. Kind of like the priciple behind the SVEA 123 stove. Either that or a burner/spreader plate of some kind ...as is used in most pressure stoves. The way the pressure is regulated in the Borde bomb, is that only the fuel in the pipe loop is getting heated from the flame, so once it's hot enough to jet, it self-sustains and doesnt over pressurise. That's going to be the problem with this design I think.

you may well be right, im going to play with this though untill i get it right, i really want to make it work well for fast brewing on the go, with a nice fuel thats semi friendly...

 

[Martyn]

you may well be right, im going to play with this though untill i get it right, i really want to make it work well for fast brewing on the go, with a nice fuel thats semi friendly...

I cant see why it woudn't work Chris. I reckon you just have to play around with the jet sizes, number of them, placement etc until you hit on a combo that self-sustains with a candle flame under it. Might take a few prototypes but there will be a sweet spot somewhere. Might be a bit of a gas guzzler though.

 

[lannyman8]

I cant see why it woudn't work Chris. I reckon you just have to play around with the jet sizes, number of them, placement etc until you hit on a combo that self-sustains with a candle flame under it. Might take a few prototypes but there will be a sweet spot somewhere.

im going to move the vent holes to the upper rim, that way it should keep the pressure in the top more, and then self combust and just put the 1 hole in so less fuel/gas can escape which should make it more fuel friendly.... and try the candle and see how that goes, if not i will make a very small lip balm tin stove to make the fuel last longer, its also a back up stove if needed....