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Dan Durston
(dandydan) - M

Locale: Cascadia
Starlyte on 04/03/2013 20:00:21 MDT Print View

"So, do you need to raise the stove, or can you just drop the pot?"
Ideally you cut the cone down so the pot sits at the right height. The saves weight and the cone packs up even smaller, thus freeing up more pot space for other items. Raising the stove/dropping the pot is a good way to experimentally achieve the right height and it's fine to do long term if you'd rather keep the option open to go back to the 12-10.

The dimensions of different Sidewinders vary, but in short you want your pot roughly 1.8 - 2" off the ground with the Starlyte (I don't have my numbers in front of me, and it does vary a little cone to cone since diameters/cone volume varies). I think the smaller Sidewinders (0.6L) position the pot a bit high even with the stakes gone, so you need to jack the stove or trim the cone, the 0.9L sidewinder is a bit high too, while the 1.3L puts it pretty close to ideal or a bit low and the bigger sidewinders MIGHT put the pot too low without the stakes.

"What has been surprising has been the Starlytes in the Cone for the Keg. They maintain their efficiency, but the speed of heating is boosted"
Interesting. I suspect what is happening here is that in the smaller cone, the Starlyte stove is getting hotter which increases the rate of fuel evaporation and thus we get even more fuel being burned (even hotter still) until eventually it reaches an equilibrium (or achieves a melt down). Dan/Zelph, have you ever gotten a Starlyte so hot it runs into problems? I wonder if there is any danger of approaching the temperature limits? If not, some sort of device that reflects tons of heat back on the stove (ie. sort of an inner cup) might lead to really fast boils (and faster fuel usage).

Edited by dandydan on 04/03/2013 20:11:29 MDT.

William Chilton
(WilliamC3) - MLife

Locale: Antakya
Re: Starlyte on 04/03/2013 23:53:06 MDT Print View

Dan, I can understand stoves getting hotter and faster fuel evaporation leading to faster/hotter burning. I've read several threads (about other stoves) where this appears to happen. However, it always appears to be accompanied by higher fuel use. What I don't understand is that with the Starlyte in the Keg-F cone, fuel consumption decreased.

Dan Durston
(dandydan) - M

Locale: Cascadia
Cones on 04/04/2013 06:40:09 MDT Print View

Fair enough - that is surprising.

Jon Fong
(jonfong) - F

Re: Re: Starlyte on 04/04/2013 11:11:57 MDT Print View

First off, it is a well-designed stove. You are correct in that when alcohol stoves are in a hotter environment, they tend to vaporize faster. That being said, faster vaporization doesn’t always lead to inefficiencies. In my experience, wick based stoves tend to throttle the vaporization rate a bit (in the direction of goodness). If the flame pattern spreads larger, but still remains small relative to the pot diameter you are good to go. There is also the thermal integration with the long skinny pot inside the tall, skinny cone. Weird things can happen at the system level. My 2 cents - Jon

Harald Hope

Locale: East Bay
quick note on 04/04/2013 17:12:25 MDT Print View

I believe that stove comparison could use an update, I am easily able to not only match, but exceed, what sgt rock reports for not only his cat stove, but (by far) the pepsi can stove he used, in my current testing, and that's with a simple penny stove that takes maybe 20 minutes give or take to make (how to will be forthcoming). And this is with narrow pots, not wide. A 900 ml and a 750ml, the 750 is slightly wider and squatter than the 900ml.

I'll post more complete results later, but this AM, for example, outside, with a real wind, not stove fan updraft, I was able to get a 17.5 ml boil of 500ml with over 1 minute of boiling, rolling, with a new pepsi can stove I tried this morning.

Last night, in tests, I got to 99.5C/211.1F temperature, not quite 100/212, but pretty darned close, using a digital deep fryer thermometer. Outside temp about 16C, water temp 25C, roughly.

I haven't yet tested minimum fuel to boil 500 ml in this latest pepsi can stove, penny style, modified, but it looks like 15ml would not be far off the mark, ie, 11.4 grams, ie, 0.4oz per 500 ml boil, which is only .1 oz per boil difference from gas cannister stoves from what I gather, give or take.

However, I am also finding that the height of the windscreen, when there is wind present, ie, real world situation, not indoor test, is very important, a 4" screen just does not cut it, a 5" one does ( assume there's a wind vortex or something that forms and goes down to the flame area at 4", but not at 5", not sure yet), with same stove/stand, slightly different pots, and wind screens 1 inch difference, it's interesting to see the differences, it's between a full boil with 1minute of boiling to not quite reaching a full boil at all, not sure why or what the actual difference is, I'm going to pursue that a bit more fully to see if I can pinpoint it, the shorter screen goes with a very thin walled stainless steal pot I found, so it may be a difference in how heat is reflected back to the stove, I"m not sure yet.

For economies sake, I am using slx, but for heaven's sake, do NOT use this stuff indoors, I consulted with a real chemistry professor, and he said students are not allowed to even open methanol without using the enclosed, ventilation fan running, toxic chemical handling boxes, whereas of course, ethanol is just fine. So the somewhat glib assumptions of safety re handling high methanol content fuels like HEET/slx might be worth a thought if you care about your health.

Re the cone holding up the pot, in early tests last year, or the year before, the heat would slightly deform the screen, and make getting the pot out a real challenge, which is when I stopped using method, I like to be able to lift the pot out easily, without having to get the screen off. That's when I decided to go with the straight screens, I'm suspecting that what is wrong is not the cone/no cone shape, but rather simply too short straight screens, which are too far from the pot walls, ie, diameter is too big. I'm using, after a lot of testing, pot diameter + .8 inches screen diameter, ie, a .4 inch gap. This can be easily tested however. But I have been noticing 4" screens being sold, and in my opinion those are too short, and will cost you far more in extra fuel consumed than they will save in weight.

Edited by hhope on 04/04/2013 17:34:20 MDT.

John Coyle

Locale: NorCal
Caldera Cone Under Glass on 04/04/2013 17:25:37 MDT Print View

Well I got my two Starlyte stoves with lids in today and I tried two preliminary burns on top of my stove at home. I don't have time for a lot of testing because I help out at my church on Thursdays, but here is what I did on a preliminary basis.

In the first test I used an MSR Titan .85L pot with a four row hardware cloth potstand from smokeeater908. I carefully measured out 1/2 oz of SLX alcohol fuel and put it in the REGULAR Starlyte which was sitting directly on the kitchen stove-not jacked up. I did not use a windscreen. I didn't keep track of the time because I am more interested in fuel consumption than speed of boiling. The Starlyte not only boiled the two cups of water, but the water continued to boil for several minutes after boiling was achieved.

On the second test I used the Caldera Cone Sidewinder Ti-Tri cone with the ,9L REI/Evernew pot. I used the MODIFIED Starlye on top of two layers of carbon felt from MiniBullDesigns. I think it jacked it up about 1/2 inch, but I didn't measure it. I did not use the tent stakes to elevate the pot but rested it directly on the cone. Again, using 1/2 oz of SLX the two cups of water boiled and continued to boil for several minutes after initial boil.

I've been fooling around with alcohol stoves for about 3 years and this is pretty impressive performance in terms of fuel consumption. With most alcohol stoves it would take about 3/4 oz of fuel to get the same results. Due to time constraints, I didn't get to read any of the comments since my last post, so I apologize for that. When I have more time, I can read through all the posts and do some more testing. The real test is outside under field conditions.

Harald Hope

Locale: East Bay
test outside on 04/04/2013 17:40:10 MDT Print View

do make sure to test outside, indoor testing, due to the lack of moving air, removes a key variable, and a critical one.

But those are great fuel consumption/boil times for the starlight design, it's clear that alcohol stove/cannister stove reviews need to do a lot more homework before they make claims of any alleged weigh savings etc.

Also of course make sure your measuring device for the alcohol is accurate, I found that using tablespoons or tblspn measuring sets have a huge margin of error in the actual quantity, so I use an irrigation syringe, 10 ml size, to calibrate the measuring mini cup I use, which I mark in 2.5 ml intervals, my initial attempts to do that without the correctly marked syringe were over 15% off, maybe 20%, not sure.

Jon Fong
(jonfong) - F

Maybe it's time to revisit Sgt. Rock's Ion Stove with the Caldera Cone on 04/04/2013 17:40:22 MDT Print View

Sgt. Rock did a lot of work on the Ion stove:

He was able to boil two cups using 12 ml in about 8:30. I tried making his stove and it required 13 ml and the time was a bit longer. Given a nice Sidewinder with the right shims, it may be a practical way to get to a super efficient system. My 2 Cents - Jon

Harald Hope

Locale: East Bay
yep on 04/04/2013 17:50:32 MDT Print View

yeah, I read the sgt rock ion stove article, that was very interesting, he's clearly doing very solid research, which is refreshing to see, and it's what made me decide to test an optimized, slower burning, penny stove design. I wish there were some way to get smaller pieces of insulation so I could test that difference, ace hardware has a very small roll, but it's still gigantic for my needs. The article he should update is the older one, where his fuel consumption / heat reached is way out of date, even for him. I've come across that article many times googling and following stove talk, so it's something that is cited frequently, as it was here for example.

However, once you get the flames down in size, the height of the pot stand gets more critical, and that's a variable I'm not really testing at this point because it's too hard to make an adjustable height pot stand, I did make adjustable diameter wind screens to find the optimal diameter, and that was very useful.

However, I believe though I'm not certain that the more efficient the stove is, the weaker the flame, and the more prone to wind the design will be, ie, these designs have to be tested out in the open air with moving wind etc, not at home inside, otherwise it's not a fair test.

For example, lifting up the wind screen off the ground outside, in the wind, is going to create a lot of turbulence and probably ruin the burn time, in fact, I would guess the water would never boil at all in a windy situation with the screen lifted up all around the edges. so to me that's not a real thing.

If I'm not mistaken, your stoves are also non too shabby when it comes to efficiency, heh.

By the way, given that most gas cannister stoves say not use a wind screen at all, one has to wonder what their true real world efficiency is outside. Or with a partial, top only windscreen, etc, another area I just see no real data, except for the jetboil. I'm trying to do most of my testing outside, both for accuracy and real world conditions, and because slx is toxic and should not be burned inside for any reason.

Edited by hhope on 04/04/2013 18:01:25 MDT.

Dan Yeruski
(zelph) - MLife

Re: yep on 04/09/2013 15:08:29 MDT Print View

Stove designing takes a lot of time and effort. Sgt. Rock kinda set a "Bench Mark" for us. Optimum Conditions to start with. No breeze, 70 degree starting water and air temperatures. Denatured alcohol was the most used at the time of his stove testing career. It takes me many many hours of design and testing to get a stove to a place that I can place it in the hands of people that become interested in it. I first start out by showing a design in a DIY thread. If people like it they voice their opinions and ask if they will be for sale. Ask in private and in a thread. I don't let anything out the door unless I (emphasis on I) like it and will use it.

Once a stove has been designed to boil 2 cups of water under optimum conditions by using 1/2 ounce of denatured alcohol using an aluminum pot with 2.5 cup capacity, only then will I deem it a good stove worthy of making available for purchase or gift.

Once it gets off the benc it's up to us as individuals to make it perform the best we can under "field" conditions.

sent from mcdonalds free WIFI camping station southern illinois, weather is great!!! wish you were here :-)