Fossil. from the little I know about gas and canisters, I think it is generally safer to pierce cans that are as full as possible. If you take natural gas as an example: it may/can explode if subjected to a spark/ignition source (maybe you drilling in to the can) if it is at 10-15% volume, whereas it will be safe at other volumes (90% etc.). The classic example of this is when the I.R.A. tried to blow up a gasometer some years back. It only burned, as it was full.
One of the other considerations (if we take propane/butane as an example) is that escaping liquid may be very cold. As you will probably know, propane escaping from a cylinder as a liquid will come out at minus 73c.
I have cut several "femresh" type or medical aerosol canisters in the past, but as i was not worried about explosions, I first emptied them fully, then I simply cut them directly to the required size with a tube cutter.
However if you were determined to drill into any canister, it may be safer to mount your drill in a vice or other device, and then push the canister onto it. Thus any escaping gas or liquid would vent towards the drill, and not you. And yes it may be a good idea to cover your drill in a plastic bag first, to avoid it getting the "salon" look, from a full cans worth of hair spray etc.
You mentioned that you use bag ties to fasten hardware cloth pan supports.
Why not simply use the horizontal wires and bend them around the vertical at the 'other side' (i.e. cut off the last vertical, leaving exposed horizontals)? You could even make them into hooks that could be undone to allow the diameter of the support to be adjusted/wrapped around a bottle.
You could fine tune the size by selecting the position of the hook/bend on the exposed horizontal wire.
Charles the Kiwi (sorry for the long delay in replying)
The gold-coloured aluminium bottles for the WBS clone were 'Joshua Galvin Protective Leave-In Conditioner' (or something to do with protecting your hair from the sun). They came in a three-pack, wrapped in cellophane, and had red pump tops. There's loads left in my branch; it's foul muck. Plus a huge assortment of other aluminium bottles; sadly, mostly aerosols, so no neck to speak of.
Last night's experiments included trying one of my open-topped burners as a side-burner, to work like Ray's close-to-the-top jet suggestion. I couldn't get the thing to prime and not put the jets out when I put a pan on top.
I tried lowering the pan to pre-warm it, but couldn't get the flame ring to survive.
What I did notice is that the flame lost its yellow tips as I lowered the pan, and, when I raised the pan again, and the yellow flame returned, the hot water started to bubble.
So I need to experiment with burner to pan separation. I think the bubbling thing isn't because the flame is giving more heat, but rather that it is concentrating the heat in a smaller spot.
I also made a centre-jetting low-pressure red bull burner, which primed quickly with a little spilt fuel, and gave a nice narrow flame ring, which is what I was looking for to use with small diameter pans. I used 12 0.8mm jets, just around the inner diameter of the dimple. The flame was a little yellow, but I'll experiment with pan height as above to see if I can fix that. I didn't do any timed tests.
The advantage of this stove is that is doesn't need an inner wall or the removal of the dimple. The minor disadvantage is the faff of priming.
Then I went on to start work on the Fresh Box Stove, cutting the top and bottom off the bottle. I've drilled 10 0.8mm holes in the walls, and mated the two halves, and I'll try it out tonight.
Hi CP, I could use the existing wire to form the join in my pot stands, and have done often. And have also done all the things you mention, such as matching pot/bottle size to the stand. For a while I toyed with the idea of having hooks so that the pot stand could be "undone", and perhaps even stored flat, but this proved more troublesome than it was worth.
The advantages of using bag ties are:
They can be used with many types of pot stand material (such as disposable bbq grill tops, which are ultra strong, and also act as a form of wind shield)
If necessarily they can be tied more losely to allow the stand size to be adjusted, but also prevent it from accidentily opening.
They are lighter than wire (this is almost irrelivent in weight terms, but is a mental thing, and a good after dinner food topic)
most importantly, wheras most folks bend their wire stays around the nearest vertical join (in the other side of the pot stand) wire can be wrapped in a figure 8 style (simultaniously around both the vertical and horizontal) so that it prvents the two joined halves being able to move up or down against each other (this means that you need less ties than wires, which are often placed: one above, and one below the opposing horizontal joints.
lastly (for now LOL), it needs no tools to make this joint, so is easy to do out in the field.
Hi Bog trotter. I don't know if you actually have the gear mentioned in your link, but having looked at it a few things struck me....
Hi Ray, I bought the side burner option so I didn't need the stand. It does look rather clumsy, and not really needed..
Making them yourself vs. getting out more.. Making them yourself can become rather obsessive with the result that you never achieve the ultimate you 'could' create. For a few quid, I'd rather get out more and admire others meths burner creations. (I have yet to see one actually being used )
Hi bog, your post made me chuckle. Yes I know I said I should get out more... but I do actually get outdoors for a good walk every day. If you lived closer to me, then maybe you might catch a glimpse of an illusive meths stove in action ( I use mine between 2 and 4 times per week).
For my own personal use, I will just pick up whichever stove comes to hand, And often swap stove varieties, "to keep my hand in". So whenever I'm out to go lightweight I'll take a pepsi/coke stove, but during my afternoon or evening walks I could use anything from meths, gas, hexi or petrol stoves or even just a flask.
I only get fussy, or into fine detail when I make stoves for others. I have 50 stoves to knock up soon, and it then becomes sensible to get the best results, use the least material, and get production down to the shortest time.
Sadly at the momoment I only get out three nights per week, but I guess that isnt too bad (plus it gives me time to work on my 10g 150mm "Y " profile aluminium pegs )
I have some questions for the q&a part of this thread please!
Anyone have any thoughts on the possible use of the smaller tins from tuna fish, with the ring pull lids on them, that come in the little cardboard over-wrap packs of threes? Also basic sardine can type tins that are shallow and long/thin too. A lot of USA blogs of folks talk of using this type of food can for stoves on the trail very successfully indeed. I cannot give any definite locations for this online, but take my word they are mentioned a lot it seems to me. And too, they sadly do not go into too much of the details on their construction either, more's the pity! I'm not worried about the longer life/more robust sourcing of Alu type metal cans as such here, for my future stoves I want to construct. I know that Frum, and others say they're superior things to use because they don't tend to degrade and rust in use in the outdoors environment.
That long lastingness of constrution approach is not a problem here in my mind for me. I am mostly here really thinking of improvisational emergency expediency first off, more than any other criteria in the design and construction process. Something that if needs be must, can be built there on site rather than being home made then trekked in with ones kit overall. I think it more of a survival skill that might well one day come in handy, to be able to fabricate an expedient stove if I had to. For instance then and there on a trail somewhere in the world, if my own stove has been lost to me by theft or accident.I just feel I could do with learning to jury-rig up a replacement to be going on with in the wilds. An efficient, viable workable stove for essentials like cooking ones food over and too boiling water upon. For the basics of outdoors survival, at the end of the day, safe food and purified water.
So, primarily I am concerned with just first off what I might well indeed be able to build on the trail there maybe. Out of those easy to find discarded food cans and all. None of this fine finishes, or pleasing to the eye 'factory' production line 'look' necessarily speaking here then! I do realise that lots of you guys are first off trying very hard to achieve that nice stunning attractive end result though. But what if you had to just only do the job out there, not in your workshops on benches, with nice power tools and handy vices though?
Hi trevor. The cat stoves you talk of are very useful, and very easy to construct. When I used to teach survival techniques to military personnel, these were always favourites with students. Not only can they be made from cans scavaged from anywhere, but if you had a tin of food, then the tin itself can become the stove.
Funnily enough, this type of stove can also be used to boil or simmer with. For boiling, the stove can be used with just fuel inside (meths, alcohol, twigs, petrol, deisol, parrafin, kerosene, hexamine etc.), but to simmer with them, or conserve fuel, you can fill them with sand or small stones, or gritty soil. This acts as a wick and thus slows the fuel combustion rate.
Another way to control the heat input into your food (in wilderness use) would be to suspend your pot avove the cooker, and then raise or lower it depending on the level of heating you require. this can be done in several ways, including suspension from an improvised "a" frame, or on a platform of stones.
These stoves do burn fairly slowly compared to commercial items, and are also not very fuel efficient.
I have personally used this type of stove quite a lot, and used to manufacture them in the field, as and when required. For fuel I often "borrowed" a small amount from any vehicle nearby, beit a landrover (petrol/deisol) or a helicopter (avcat/kero)
As stated somewhere above, for cold weather it would be advisable to try to obtain a second can to invert and place under the stove to act as an insulator/cold barrier.
Tools needed to construct this type of stove could be:
a knife or
scissors or
an old style tin opener or
a screwdriver or
even bashing the tin with a pointy stone for long enough.
Sorry I dont have any online links to put up, but I'm sure CP or someone else will oblige.
> Sorry I dont have any online links to put up, but I'm sure CP or someone else will oblige
The Cat stove is probably to be found at the Wings archive (see my list of links earlier in the thread), but I don't actually read too many websites, preferring to get on with my own thing most of the time. Google is your friend.
In those last pics there CP thats an interesting looking potstand, is it home made?
Thats where Ive been putting my jets on my last batch of stoves (as on the coke one in my last lot of pics) I got some confusing results though.
I tried the coke can stove(see my last pics) which has 8 jets pointed at the centre and gives a good flame pattern for narrow pots (Alpkit mug). also had two other stoves of the same design except one had 16 jets and the other had 32 jets all pointed in the centre.
The 8 jet coke stove I couldnt get it to give the same performance as last week? all the conditions fuel amounts etc were the same but it ept burning out at approx 8min30sec and not quite acheiving a boil.
The 16jet one I had high hopes for didnt quite achieve a boil either but it did run on the same amount of meths for a staggering 21 mins.
The 32 jet one did achieve a boil in 21min 30 sec and ran out of fuel abou a min later. I nearly fell asleep waiting on it!
I had really high hopes for the 16 jet stove and am a biot dissappointed. Something must be different though to get such varying results from the same stove though (8 jet)
BBF, it's a Mini Trangia potstand/windshield. It's about the right height for the red bull burners, so I've used it for my timed measurements to get a consistency (all my tests have been with 20ml of fuel, 500ml of tapwater in the Trangia 27 Duossal pot, and Mini Trangia lid). I picked it up in a clearance sale in my local Millets quite recently... It's also good because the flame is visible for photos...
How much water are you trying to heat? The Alpkit mug is only 750ml, so I don't understand why you're not getting a boil in about ten minutes, even with the pot filled to the brim. (oh, looking back, I see you may have been using 450ml).
I regularly get a boil in about 7 minutes, whatever design of burner I use. And most of the burners jet until the fuel is used up. With the open top burners (Trangia-like), the jets lose their oomph when the fuel falls below the fuel ports in the inner wall; pressure in the outer wall is thus lost.
I wonder if you're demonstrating how poor a conductor Ti is...
Did you use the same construction method for all the stoves? i.e. were the inner and outer can parts the same depth in all cases? I'm wondering if you're suffering from a problem of what we might call carburation; the fuel not vapourising, because heat isn't getting to the fuel.
Oh; the little Fresh Box Stove burnt for an amazing 6m30s on 5ml of fuel. It managed to boil the 100ml of water in the mackerel tin (which was lying around handy in the recycling pile after I lit the stove; I was so shocked that it worked I wasn't ready with water...) in about 4 minutes.
> Hi CP, I could use the existing wire to form the join in my pot stands
Yes, it was such an obvious idea, I didn't think it was original. It's interesting how we have different views of what is 'good'; we're each using different judgement criteria to assess the same thing. I like the idea of using just one material to make something, as that seems elegant to me; looking back over my posts, I can see this aspect of my thinking coming out, e.g. dislike of JB Weld and rivets. But I can equally understand the versatility of a bag tie.
> wheras most folks bend their wire stays around the nearest vertical join
I'd envisaged bending one horizontal wire up, and one down, so that they mate above and below the opposite horizontal. This holds the two ends stable relative to each other.
Oh; the little Fresh Box Stove burnt for an amazing 6m30s on 5ml of fuel. It managed to boil the 100ml of water in the mackerel tin (which was lying around handy in the recycling pile after I lit the stove; I was so shocked that it worked I wasn't ready with water...) in about 4 minutes.
I also have a mackeral tin in my recycling pile, so I put 100ml of water in, and with 5ml of fuel achieved a rolling boil in 1min 56secs. The fuel ran out at 2min 39sec. When everything cools down I'll run another test with same water and fuel volumes on my "fuel economy" stove.
The Fresh Box Stove is just a bit of fun, Frum... I can't imagine it actually being useful; I was just amazed that it even worked at all...
I've started looking at energy contents of fuels, with a view to trying to calculate actual energy efficiencies. Oddly, there seems to be quite a variation in quoted bond energies that come up online. And bond energies aren't necessarily the best way of calculating heats of combustion. But it's a start...
I've just done the duation test. 5mls fuel, 100 mls water. 3min 50 to rolling boil, 6min 12 sec to burnout.
As you say CP, this test was just a bit of fun, but it made me think. That mackeral/sardine tin holds just over 150ml - almost a teacupfull. So I weighed the tin, plus my economy stove, plus a wire potstand and it came to 26 gms. When I added the fuel bottle the total was 44gms (1 1/2 oz) for a nice little daywalkers cuppa kit.
)
I just feel I could do with learning to jury-rig up a replacement to be going on with in the wilds. An efficient, viable workable stove for essentials like cooking ones food over and too boiling water upon. For the basics of outdoors survival, at the end of the day, safe food and purified water. 
