Ian, After looking at that link again I see the solution was there all along. How my idea differs (I think) is you wouldn't need the internal grate as the bottom of the burner can would suffice. the vent is definitely more complicated than it needs to be though. Oh well,...........I'll start looking for cans. it's still chilly outside and the days are too short. it'll give me something to do.
Hi Ian, The stove is a pressurized gas burner (coleman fuel) so it would run fine as a standalone or with a windscreen. The idea I am considering is to have a windscreen that is heatproof enough with some additional components to also be reconfigured into a wood burner with the gas stove left in the pack. Then I would have a fastpack system for either fuel with full winter capability, and a reasonably low weight.. I need to now just focus on woodburners to learn the ins and outs and full capability, then make a windsreen adaption from steel and if that works, make the titanium version later being careful not to waste the material I scrounged for a reasonably low cost. Meanwhile the thread is getting quite lively just on the woodburner design and it is very interesting. Regards, Doug
Ian: The "gas wick" cited in the linked article is not described as far as I can see. Is it yet another can? Have you tried the Kalmin 70 riser sleeve? If so, how is it to work with? Pete
Never mind about the gas wick - found it: "The gas wick is a smaller diameter can suspended by wires inside the larger coffee can with its closed bottom up. The wick become very hot and draws gas and air up along its sides, and prevents air from going down the chimney." http://zenstoves.net/Wood.htm Pete
Sorry, you had me confused on the wick question. I will get around to reviewing the sites you have givern links for. It's all good stuff ! Doug
For those curious folk out there............at the time of the thread's beginning I had no shots of the smaller stove I talked about so this morning I fired it up and took a few shots for those interested. The stove to the left of the one burning is the one from earlier pictures I posted after being out in the weather a month and the stove to the right of the one burning is a similar stove that I copied off the internet but did not like the way it performed. The air space between the two cans was insufficient. There is a small can sitting underneath the stove with fire, ignore it, it is there only to keep heat away from my wooden deck and is not part of the stove. In conjuntion with the stove, I utilize a small windscreen/chimney (shown both on and off). Notice how the shape of the flame changes with it on! It helps to concentrate the flame to the middle by injecting air from the perimeter of the stove towards the middle. The pot support is nothing more than a length of 1/2 inch hardware cloth(parly visible at far left) that stands less than an inch higher than the chimney and one goes inside the other and both sit together on top of the stove.
I knew somebody would ask me so I took these to explain the pot support and windscreen working together and you can see how they can be used together or alone or not at all. Just the pot support. Screen and support used together. And finally the star of the show..........the pot. The windscreen does sit down better than shown but it was friggin hot and I burnt my fingers (almost) trying to set it in there with the stove going. In real uses situation you would place the windscreen and pot support on securely before lighting the stove. Now visualize, the wind screen and pot support slide into the inside of the stove for stowage and inside of those is still plenty or room for a container of your favorite firestarterthat goes inside your small mug which inturn still has room for a package or two of dried soup mix/coffee/tea/sugar/whitener. Many possible combos, but you get the idea. I am extremely happy with this system but the thing that continues to elude me is a pot of aproximately 2 liter capacity that the stove can fit into. Only thing I have found so far that was capable was another slightly larger can. My 4 liter pot will work for this but that is overkill for a one person setup. Mind you, a larger pot absorbs more heat than a smaller pot due to its larger surface area exposed to the flame and using a larger pot allows for larger quantities of hot water to be heated for things like washing dishes or taking a sponge bath etc. while on the trail. I can always make up for the extra size of the pot by packing more goodies inside the pot and around the stove to make up for the lost space within the back pack. Its a trade off I guess as the weight differnce between the 2 liter and 4 liter pots is very small indeed. I seldom am alone on an adventure so the 4 liter pot is usually my preference anyway. This smaller stove that I have built is very very packable. It weighs only the amount of two empty tin cans. And......when you consider you never have to pack fuel along with you I think you will soon see it actually has a smaller use footprint than that of gas/kero stove with fuel tank, not to mention the extra weight of the fuel you have to bring along. The hardest part of using this stove is learning how to light it. For best performance it is necessary to light the stove in such a manor that the fire spreads rapidly across the entire surface of the material at the top. Once you have managed to do so you will have a very predictable burn and heat output. Anyone who has ever found themselves in a situation where they are down to one last match and desparately need to get that fire going know the feeling of importance it is to have to get it right. For times like these I carry a pre-made firestarted for times when it is just too windy to do easily. I have have had good success using cotton balls soaked in petroleum jelly (vaseline). I spread out the cotton ball as much as possible and then build a tiny tee-pee fire above it with an opening to one side to later get a match into for lighting. Once done you light the cotton ball which burns up and lights the kindling you built the tee-pee from and then that material burns down and will slowly but uniformly ignites the stoves fuel below. Voila! Perhaps that makes things a little more clear. grin Ian....
" Anyone who has ever found themselves in a situation where they are down to one last match and desparately need to get that fire going know the feeling of importance it is to have to get it right." Never been there, but I did read Jack London's "To Build a Fire" to the grandkids at the winter campout a month back.....
I would hate to run out of a way of lighting a fire, so: Standard firelighting kit for me (duplicate carried by my son), not all in one pocket though Firesteel, Army model Cotton wool balls / Vaseline Waterproof matches in sealed case Zippo Turbo gas lighter Cramp balls / King Alfred's cakes several throw away Bics A couple of tea lights Sometimes I'll have things like hexamine blocks, home made sawdust/candlewax cones (cast those in old egg boxes, work very well), charcloth etc
Ian: Once again, a detail question. The flange separating the inner and outer cans in the burning packstove, what is it? Is it, again, part of the lid cut off from the larger can or something else; it serves the purpose of holding the windscreen and pot support quite well. That windscreen is very much like the iillustrated upper can in the downdraft gasifier with the gas wick. When you tried the stove with the gas wick.... I know that you wrote that it got all smoky. Could you ascertain the cause of the poor combustion? I'm going to try one about four inches in diameter; might as well pick your brain since you've done it. Also, for a draft control - I was thinking of keeping the lower inlets on the side and fitting a sleeve with matching holes and a wire handle around the base. Turning it one way or the other would open/close the inlets. "To Build a Fire" .....not under a tree. Pete
Hahaha, good eye and good question. It's a paint can lid with the center cut out! The size is one pint. Yes the windscreen is similar to the gas wick but has nothing in the middle restricting draft such as a can in the middle of it. I tried various things to make the gas wick work such as using larger and smaller can sizes for the inner can thereby increasing and decreasing the space between it and the outer can of the wick but no luck. The wick always seemed to choke down the stove. Perhaps a greater inflow of primary air from the bottom would create a smoother flow through? Havn't tried that yet. As for your air gate........if I am following your thought line correctly it should work fine but where mine here exceeds is that it has two totally independay air supplies from one another. The primary air comes in from the bottom and is regulated with an air gate and the secondary air comes in from the bottom sides of the outter can and is independant from the primary. Your method will indeed close or open the air supply but one airgate will be restricting the air or opening up the air supplies of both primary and secondary at the same time. In no way do I know all there is to know about these stoves but what I have found with regard to air so far and I could be wrong here too is this. Controlling primary air flow controls the rate of burn and amount of heat produced from that burn rate. If there is sufficient secondary air to match that of the burn then all will burn cleanly. However, cutting back on or having an inadequate secondary air supply will produce a stove that burns incompletely, burns for less duration, and smokes because of incomplete combusiton of the gases (in the form of smoke). So, reducing primary air supply slows down the burn. Reducing secondary air inhibits clean combustion. I so far have found that you can not have too much secondary air(within reason) you can however easily have too little secondary air and the burn will degrade accordingly You want lots of secondary air You want to be able to limit primary air for burn control without limiting secondary air. In order to have both of the above, you need two independant air supplies with one of them (primary) being controllable. Make sense? Ian....
Pete, here is something that I did not mention with regard to the gas wick. Although this may be a good feature if you can get it to work and I have not yet, the reason I decided to forget about it were simplicity and safety. I wanted a stove for camping that was efficient, small, and stable. By the time you put a pot on top of this stove it is fairly tall and a little top heavy from the liquids in the pot......not overly so but none the less top heavy. Now consider putting that pot another 5 inches higher yet by adding the wick section in between the stove and the pot and it starts to resemble a clown balancing a chair on the end of his nose. I just felt it was too ungainly for camping purposes. When you stop to consider that the stove and wick design were developed for use indoors it is a little different when you have flat cooking surfaces with known solidity. The wick was also to enhance the cleanlyness of the burn. They claim a blue flame burn but I don't see how that is possible anywhere in the burn cycle except in the transition area between gasifycation and charcoal phases. For camping purposes................realistically it is a mute point. The stove does everything we need it to do without the wick and is one half the size it would be with the wick. Big Bonus! You will probably want to try it anyway.......I did. Let me know if you have success. Ian....
