The Allen screw is a super idea you had, IMHO. The pop rivets are so easy to use... why not? <shrug> But I was just using what I had laying around - I wouldn't use anything smaller than a #8 opening, tho - actually, if I hadn't had those rivets, I would have used a 1/4-28 NF nut and bolt or a 6.0mmx1.0 nut and bolt - about the size of a #10, roughly. A 1 oz medicine cup (e.g. Nyquil) is another handy (free) measuring device that works well.<br><br>We found that a #60 drill bit makes holes rather larger than optimum - most of these fellows refer to a "0.024" or "0.025" - that's about a #70 drill - TINY (the "regular" sizes go down to a #80). I suspect that within reason (say, no bigger than 1/32" - 0.03125" nominal) the hole size is not critical as long as the total "area" (sum of the holes) is not too much. We're piercing holes that are ~0.027" but they spring back a few thou smaller - IOW, right at the target size. But hey, if it works...<br><br>Also fiddled with the angles on the inner ring of holes - we think that if the inner jets don't combine into a single flame it burns a little cleaner - but it all boils the same near as we can tell.<br><br>Not being terribly patient with JB Weld's 15 hour cure time... after intitial set, we pop the epoxied parts into an oven warmed up to ~200 deg-F (heat turned off then) and in short order - about an hour - the JB Weld is fully cured. That's windscreen and pot support fabrication time...<br><br>Piggy-backing a reply to P_L here: I'm in agreement about the pot support not being versitile for smaller pots, but it works - I can fiddle this to death or just let the lads use 'em. Or both <grin>. The main thing I dislike about this whole setup is the number of discrete parts. There is an all-in-one (two parts, actually) alternative approach using a coffee can... hmmm. Seems bulky. Also, my math agrees with yours - longer trips, the commercial stoves with higher BTU value fuel are "better". OTOH, these are great for cash-strapped folks (kids) and they are reasonably safe. Heck, they work fine.<br><br>Regards to all,<br><br>Tom<br><br>

Actually, just to clarify- it wasn't the pot support I was worried about so much as the foil/flashing windscreen. I'm sure it's much more efficient to have it very close around the pot like that, but it doesn't seem very versatile- if you were carrying two pots, or a pot and a pan, it could be a problem. Or maybe you just open it up wider on the downwind side until it fits?<br><br>I think the idea has a lot of virtues, not just for kids, but for lots of short informal trips. It will take some mental re-training though, for me to figure out how long I want the stove to burn before lighting it each time. I'm sort of used to just turning it off when it's done...<br>

>>>Piggy-backing a reply to P_L here: I'm in agreement about the pot support not being versitile for smaller pots, but it works <<<br><br>Okay.. What if ....<br><br>Take the bending of the prongs idea to a new level. First, make the support screen about an inch too high. Next, clip off the horizontal wires strating from the top edge down an inch so you're left with a circle of 1 inch prongs. Form the screen into a cylander, just as you would for use, then use a needle nose pliers to bend them in towards the circle, forming a star configuration. <br><br>This would allow you to put smaller diameter cups on the stove. <br><br>And it still takes up the same amout of storage space. You could flip it over on the tuna can base, the pop can bottom dome should sit in the center of the star. Drop the empty stove on top.<br><br>BTW, I made my wire stand according to the deminsions on the instructions and the two ends of the cylander are about an inch short of meeting. Is there a reason for this? I'd prefer to cut the piece a bit longer to the two end come together. Then use a small wire hook, like a Christmas ornament hanger, to keep the gap secure.<br><br>

>>>It will take some mental re-training though, for me to figure out how long I want the stove to burn before lighting it each time. <<<<br><br>Measure the fuel amounts and record the burn time, amount of liquid and weather. eventually, you'll have a crib sheet to use.

If i remember the gap in the stand was for a damper to be installed to give you a simmer setting. <br><br>Didn't think about bending over the wire to make the stand less sharp and a little stronger, but it should work well as long as it doesn't extend to far into the flame. The first stand i made a little small to make it take up less room, the burner would heat the ends of the wire up to red hot. Which on small wire decreases the structural integrity quite a bit.<br><br>Personally i side with Tom on making the holes, used a scribe to make the pop rivet hole and a needle in vicegrips for the burner holes. And just to rub it in a little i do have drills in stock down to #80. However, i didn't have the rivet nuts on the shelf which is why i used a rivet and taped it. <br><br>I think the best concept to take away from this thread (the stable bottle is the best)is to use what you have and try it. This is not something that should be complicated, it's cheap and easy to fabricate. Make several with different burner configurations or fill options and see which one you like the best. And then send the one you like the best (or the least) to Chris for testing and evaluation.<br><br><br><br>

We made these windscreens from flashing to fit the "largest" kettle/pot they may use + about 1/4 - 1/2 inch gap. Used 1/2 width of a 12" wide roll - i.e., 6" high. <br><br>They simply "close down" to a smaller diameter for smaller diameter pots, altho I note that (coincidentally) all but one of the pots they own between the three of them is "close enough" to the same as max diameter to not matter. Pots/kettles with bales are handier for them (this isn't going to used with a skillet, but a cut-down area on the flashing would accomodate side-handled cookwear).<br><br>Corners are radiused on the flashing. I think I would like a dead-soft aluminum windscreen a la MSR better, but the lads are happy with these and they sure work well..<br><br>The pot stands, as you also suggested, have the "tabs" of cut wire bent and crimped around the cross wires (alternate directions to avoid bursting a joint). Something to do while waiting for the JB Weld to cure in the oven... We did not leave a gap in the hardware cloth, choosing to use about 12" long piece that is a bit taller than suggested. No simmer ring <shrug> - these are for boiling water as we see it.<br><br>1 oz of denatured (ethanol) alcohol brings a full quart (32 fl oz) of water to a rolling boil and holds it there briefly with any of the stoves. Mild breeze, ~600 ft ASL, 48 deg-F water and 41 deg-F ambient temperature. This includes all fuel used (preheat fuel sprinkled out of the filled burner). One of the stoves is faster - 4 1/2 minutes to full boil. The other two take just under 6 minutes. No simple explanation for the difference. BTW, times are ignition-to-boil (kettle pre-filled with water and fuel pre-measured and poured into the burner)<br><br>Oddly enough... 1/2 oz fuel boils 1/2 quart (16 fl oz) of water (barely)... Two quarts of water can be boiled with roughly 1.8 oz of fuel thus: Boil one quart. As soon as it is rolling, remove kettle and place a second kettle on the stove. The exact amount of fuel required varies between the three stoves. I fully expect that cold conditions will require a slight increase in fuel (preheat will take more). I have not checked BTU potential values to see if this all even makes sense - it's just empirical results.<br><br>Tests were done with an MSR stainless steel kettle with a lid on. Bails get too hot to handle without protection. There is also considerable "waste" heat, so kettle stacking to warm or preheat the upper kettle is very possible.<br><br>Surprised at the soot (not much, but there is some). My (old) paradigm with alcohol is blue flame, no soot. Now I know better...<br><br>Finished testing... stoves are packed for the next trip. The lads have "appointments" to show some other crew members how to make personal stoves - everyone who has seen them work wants one and none have said "well, I'd rather buy a _______ stove".<br><br>Tried one stove with mineral spirits - stick to alcohol. Huge flames (not high pressure, but big flames) and tons of soot - I'm sure we made a few zillion buckyballs on that test. Took forever to burn off 1 oz of fuel and it was a PITA to preheat.<br><br>As for myself, I'm sticking with my pressurized stove - whichever one I carry. But I am mightly impressed with these "free" stoves - they work very well. An Esbit is in my "Be Prepared" pack because it's small and will boil water; otherwise I would make one of these up for me to carry as well.<br><br>

Good idea. You need to cut gussets (darts?), but it should work fine. BTW, as I expected, the flames burn the galvanizing off - do your first burns outside - prol not enuff zinc fumes to give you zinc fever, but...<br><br><< Then use a small wire hook, like a Christmas ornament hanger, to keep the gap secure >><br><br>Not needed - 12" long overlaps just fine and it all hangs together inside the tuna can rim. YMMV.

<< And then send the one you like the best (or the least) to Chris for testing and evaluation >><br><br>Hmmm... wouldn't a better test be to send Chris a "kit"? Lemme rummage thru the "to be crushed" box a bit... yep! Found several kits ready for Chris to test... <grin>

Re: Soot<br><br>One of the links from the stove site recommended painting the bottom of the pot black. This should increase heat absorbtion AND hide the soot! :-)<br><br>I need to touch up my grill this summer, so I'll try painting the bottom of my pot at the same time.

Most paints will create toxic fumes when burned, some very toxic. Please be careful.<br><br>In experimenting with painting the finned cylinders of air-cooled engines to increase cooling, it was found that many high-temperature enamels have insulating effects that defeat the purpose of the blackening. Best results I am aware of with commonly-available materials was with stove paint.