Thank you so much for all your efforts! You mentioned you don't know how people watch all the way through. I think a large part of it is your passion and attention to detail for the work shines through in the video. Its very satisfying to watch someone take a question like this to its logical conclusion and collect the best data possible.
This kind of content, I generally prefer to have documented in white papers, where I can read through them, but fire, in particular, it's good to see/hear the various conditions, which cannot be properly communicated through text and pictures.
You don’t know how we watch this all the way through? Duuude!! I’ve watched Performance Nutrition for Backpackers Series MULTIPLE times! Great information!!
Another outstanding series, and yes optimal configuration depends upon knowing your camping conditions. Number of boils per trip, wind conditions and understanding your stove all are important factors. Keep up the outstanding work!
@@GearSkeptic The test matrix may become waaaaay too big, but it would be interesting to test alternate ways to increase efficiency on the pot end. I know you looked at lids vs. no lids a while ago. I think on that video I mentioned using a stretchy silicone lid as a way to prevent boil off as opposed to a metal lid. They can be bought in tons of sizes for very little on amazon. They also have the nice benefit of providing a visual cue when the water is close to a boil. By the time enough water has evaporated to stretch the lid off the water should be up to temperature. The other thing I had in mind was a pot coozie to reduce heat loss to the environment. I'm very curious if that would make any measurable difference in either wind/no wind conditions.
Two additional observations: 1) This totally trounces all of those gear review RUclipsrs who got free Jetboil Stashes, shot wonky boil test videos and concluded it was an amazing system. 2) This video hit at the top of my feed after months since your last post. The algorithm does not appear to prioritize post frequency! And all those tags are going to give me nightmares for weeks.
The Stash is an amazing system. It's a commercial ultralight pot and stove with incredible efficiency (primarily thanks to the great pot). Prior to the Stash people had to cobble something together out of various components which most hikers, and certainly most new hikers, wouldn't do. The Stash made a highly efficient and very light system available to all.
@ It’s an ok (although expensive) system. But as Gear Skeptic’s testing proves, it is not efficient in any kind of wind. It’s too bad, because the pot is solid, but the stove is the weak point.
If JetBoil offered the Stash pot as a separate component then they would see why people buy that system. It’s very expensive for what it is. Adding a removable wind screen might make it a better system for all wind conditions.
Bravo on keeping up the high scientific standard. Must be frustrating with the high flame issue. It’s incredible how much effort goes into, but really makes me rethink the stove/pot combo I’ve been using. For that I’m grateful.
Once again, EXCELLENT video! Your testing methods are far better than any other testing I have seen on youtube, for stoves. Regarding the issue of the refilled canister causing issues. I have been refilling canisters for many years. Canisters are filled with up to 3 different gasses. Butane, IsoButane and Propane. In the canister, the butane is typically on the bottom of the canister, with the propane typically in gaseous form on top. This is specifically why some canister stoves are designed for the canister to be upside down. This enables the higher pressure propane gas to push the butane (or isobutane) out first, making your stove burn better in lower temps longer. Regarding your tests, when you refilled the canisters, if you heated the canister you want to drain, then connected the two canisters together via the valve, then opened up the valve, with the canister to drain upside down on top, you probably filled the canister you are trying to fill with mostly butane (or isobutane). Butane does not generate as much pressure and therefore will not push gas out as forcefully as a new canister, because of the lower amount of propane remaining in the cylinder. This also could explain your pressure loss issue. FYI, this type of canister works very well when refilled with 80% by weight butane, then 20% propane. I've been doing this for many years and have never had any issues either in refilling or in usage. I've seen people have their nearly new canister valve completely go nuts (probably from foreign contaminants in the valve) when screwed in and completely drain after removing from the stove.
Interesting ideas. My shop is well above vaporization temp for all gasses, though. Also, I did not transfer just a portion of what remained. I emptied them. Did not use heat, just gave it as long as it needed.
@@GearSkeptic Is it possible you previously experienced some selective evaporation with the (original) canisters, altering the ratio of propane to butane remaining in them?
@@GearSkeptic Wouldn't there naturally be higher pressure in the lower canister? Wouldn't that lower canister be filled with the most liquified gas (butane), and the propane would float to the top, being the upper canister. I'm pretty sure you ended up with the upper cylinder containing some propane and all the butane/isobutane in the lower one.
Theoretically, there can be a difference in the burn off rate of the two gasses. But, that is something likely to only be noticeable if it is so cold that you are near the latent heat of vaporization for one of them. Then the differential will be greater. But, at my shop temperature, both gasses will be at the equivalent of a “rolling boil” inside the can. So, there won’t be a difference that would be so pronounced as to account for the difference in rate I saw. As for the transfer process, it is done with the donating can upside down, so it is the liquid in question. Isobutane and propane share the same molecular bonding traits. They mix well and stay mixed to the end. While differential gas burn is at least a theoretical issue, pouring one liquid off the other isn’t. Think of it this way: if the differential burn was that strong, you would have the same problem in the canister burned down. It wouldn’t matter whether you had refilled or not. All partially-consumed canisters would end up this way. From many, many measurements, I just don’t see that happening. At least at my temperature of testing. It would interesting to see what happens when running a stove at 15F.
@@GearSkeptic I'm pretty sure the key reason Propane is added to this mix is because per weight, Propane adds more pressure to the tank. That pressure is what pushes the gas out, what makes butane actually work at all below freezing. I believe your refilled canisters do not have enough propane in them. I have absolutely NO idea how much would need to be added and therefore, suggest just using them for non-essential or critical uses. They'd be great for weekend uses, but unless you completely empty the canisters and add butane and propane by weight, you'll never really know what the ratio in those refilled canisters is... Unfortunately, this means you're stuck with requiring brand new canisters, or identically refilled ones that were emptied and refilled with strict adherence to the ratio...
Damn he's alive. I've watched through all of the Performance nutrition series the last week. I've applied all of that yesterday and I didn't return half dead after 8 hours of hiking. My problem before was drinking only water. Since I've started a year ago, I've been meticulously taking notes after every hike about any problem, feeling or consequence and improving my gear and nutrition based upon those observations. My goal is to lenghten the time I can spend outdoors in any conditions. The videos of Performance nutrition for hikers should be mandatory knownledge for any hiker, not allowed to leave the house without it.
Thank you for another well crafted, informative and unbiased video. I was very excited to see the latest installment. Watching the entire video was not a problem considering the cost of admission. I’m probably not going to be buying an HX pot anytime soon but the information you provided will stay in my back pocket.
Finally another video 😀 Please keep going and make more, go deeper and deeper into equipment, food, clothing, etc. Your work has helped me a lot in choosing the things I cary outdoors 👍👍
Always egerly look forward to your investigations. It's been a while, but that twist with the high rate valve conundrum made it worth the wait. Elements that used to make my old job fun. Nice tale, well told as always. Many thanks.👍👍👍
Very good as always. One thing that surprised the heck out of me was when I hiked in Ireland. I grabbed the same canister size I usually get and went out hiking. Two weeks later I was still on the same can. I cooked the same amount as normal, but the cans I got over there lasted me on average double what I got in the States. I ended up talking about it with a guy at one of the outfitters there. He said it's because the fuel they use there is mixed for near sea level. He said he doubted it would even work over 5000 feet. So that was a surprise.
@@GearSkeptic I just had a thought and checked the Dublin store. Turns out the stuff I used uses a 70/30 mix. The US fuels (MSR, Jetboil, and the like) use a 80/20 mix.
@@toocleanpappas5397 The more propane in the mix, the higher the canister pressure. The higher the pressure, the higher the risk of the canister rupturing, god forbid, if its next to a flame... I have tested refilling to 75/25 ratio, but don't think I would attempt going 70/30 unless I knew the canister had held that pressure previously... What brand of canisters were those you used with that ratio? THAT is the information that would be great to know...
Absolutely 💯 thrilled to see the next instalment in this series come out, immediate stop what you’re doing and press play! I am not an ultralight hiker and take great comfort personally in knowing my MSR Reactor will perform in just about any conditions, i thoroughly enjoyed your meticulous attention to detail in this video. Thank you Sincerely from Australia 🇦🇺
That's a nice story but the retailer you were talking to is clueless. Canister pressure effectively increases for all pressure vessels as you gain altitude because the air is thinner. There is LESS force fighting the escaping gas so canisters work better in terms of fuel flow. The counter is your water also boils faster at a lower temp so it takes a bit longer to cook food.
Outstanding work, again! We watch all the way through because you are thorough, unbiased, and take a scientific approach. I use a Zip, Minimo or Trangia 27 (with Storm gas burner) depending on my trip. My informal tests show my Trangia 27 (at medium flame) to be slightly higher in gas consumption but not much in it. I know the Trangia system is less popular in USA than Europe, and it isn't for the weight conscious, but I'd love to see you put a Trangia 27 + Storm burner though it's paces!
Ah..For me alcohol stoves don't make sense: riskier to use near a tent, and my fuel usage makes has a no brainer from a weight/efficiency perspective. Trangia 27 started as an alcohol stove but the Storm gas burner gives the stove a different set of advantages. Cheers from UK!
Thanks for all your work on this, it's bugged me for ages whether it's worth the extra weight to carry my reactor. I was thinking, i need to plug this data into a spreadsheet so I know when it's worth bringing, then if course you say you've already done this and made it available for download. You're a legend. And I'll watch any video you put out in full, sometimes a second time because it didn't all sink in the first time
Dang, another fantastic presentation! While you’ve made the point that there is no perfect system, I’m happy to have my titanium pot and tiny lightweight burner! I do all my boiling behind my vestibule with minimal wind.
@@GearSkeptic However, all your data collection and analysis is bang on, thank you for all the time & effort you put into these. I've noticed my cannister refills seem to be a little weaker at WOT also...wonder if that's a potential point of failure over time?
@@GearSkeptic I posted a reply above about this, but I suspect when you refilled, you put the old canisters butane (low pressure) into the canister you were refilling. The propane usually stays in its gaseous state, whereas the butane is mostly a liquid. That means the propane stayed in the canister after you thought it was empty... Refilling canisters isn't realistically supposed to make the canister as good as a brand new one. It's just supposed to make a canister that works without buying a new one...
Excellent video. Appreciate the effort you put into these tests. I've some experience trying to get consistent and repeatable results testing consumer level equipment (not stoves) that aren't designed with exact adjustments as a priority. I know it can be extremely time consuming and frustrating which makes your videos even more impressive. I've owned/own 5-6 stoves so can to some extent pick the one that's most suited of a specific trip, but if I had to choose one that should work for all types trips I've done then fuel efficiency and stove + fuel weight (while certainly important) wouldn't be my top priority. Fuel availability, performance in cold and stability of the stove is even more important to me.
36:19 From one engineer to another: This effect is called stiction and it is common in control valves in industrial controls where fine tuning is of critical importance. The creep effect is also why industrial controls now use valve positioners, which keep valves at their set positions. Probably not very interesting to many, but it's completely common to those in that world.
In the end of that series we will get to an integrated can-stove-pot with only 50 grams overhead on top of the fuel weight and burning efficiency of 3.2g/boil in any wind condition.
Sorry for your inconvenience, but learning that refueling a canister can damage the valve and effectively cap the output is very useful information. I’ve never heard mention of it before, and makes me realize I should probably stop refilling the same canister I’ve filled 4 times now.
I’ve had one other problem with a refill that was an off-brand small can. That one just causes the stove to geyser up flame uncontrollably. Not safe to use any more. It is making me want to avoid refilling, but some people say they’ve done it for years without (noticing) issues.
Love the videos man. Two things, first I just keep tin foil nested in my pot and open it up as a windscreen, works for me. Second, and something I've searched for answers and none have the skills like you to dive deep into...stakes. Shape, length, angle, V Y Shepard hook, which direction the V is in, we must find out.
One other related thing I would be interested in seeing you test would be how temperature affects these stoves, and perhaps even some methods to mitigate the tendency for Iso canisters to freeze up in the cold.
@@mikekraut7643 yah, I’ve thought about extreme cold weather testing. Be tough, though. It’d have to be outside, and then controlling the environment would be hard. Also, the opportunities are rare for that.
Your dedication and rigour is quite simply extraordinary. Thank you not only for your efforts, but also for achieving your aim of demonstrating a methodology for others to examine any given question. If it means anything, I have just watched all five episodes in this series back to back. Odd as I may be, it has been a genuinely fascinating and enjoyable experience. I do have one question which might affect a “best system” decision: how many boils do you actually get out of a canister? My experience is that you never actually utilise the full amount. Might this mean that the lighter systems lose out even for shorter trips? I will attempt to work that out myself, but hope that it’s worth raising for consideration.
Interesting. I never do run the can down to where the stove actually dwindles out. I suppose I should try it, then weigh in to see how much fuel might still be left.
Fantastic! Thank you so much for the tremendous effort and time put into these videos! The revelation that ha refill valve maybe damaging a cans output is also shocking. Will you be doing more testing in this with different valves?
Well, I do have another experience with refill of a small can, off brand. That one causes the flame to just geyser up from the stove like a jet engine exhaust. Unusably dangerous. A different kind of failure, though.
oh man your error had to have been supremely frustrating. Still, you have one of the most stringent testing methodologies I have seen in this space so feel too bad, you are still far more accurate and useful that anyone else I know in these test. have you ever though of setting up a wishlist for the gear you want to test or patreon, not sponsored but from your viewers. I would imagine that you would be able to have many people who would appreciate being able to help you defray some of the cost.
Love this series as a data nerd. As another baseline, how about testing a basic UL pot/stove combo with an external, unattached windscreen. Like some thin foil cylinders, or I use a piece of kitchen aluminum foil folded a couple times, that rests on the ground and leans up against the pot, covering roughly the upwind 1/2, but still plenty of space to keep the can cool
I did a few impromptu wind break tests for the wind effects episode. I avoided the exterior, free-standing kind because those also encapsulate the canister. Don’t want to get involved in a strategy that might encourage someone to overheat their can.
I'm currently using mostly alcohol and the brs, but I do like how the HX systems have such stable fuel consumption in comparison. This would make planning much easier. But as you already talked about in the previous part, it makes only sense if I can go lighter on the can I use. The smallest can I can regularly my hand on is the medium/410ml/230g size. For a weekend hiker, I will probably never empty one in one trip. But perhaps I can check, if I can get some stable fuel use with the alcohol burner. At the moment it is a hard-to-make rough guess every time how much alcohol I need to put into the burner. Which I often don't get back when I guessed to much and becomes really "scary" if have to refuel, because there could be still a hidden flame. Here the more stable fuel usage would give me a reason to accept more weight and bulk of an HX system.
Found your channel recently and boy is it a gold mine! Would like to eventually see a video about odor resistant bags like nylofume; opsac, smelly proof, etc. Specifically, I'm wondering if I could layer them to eliminate the smell and not have to use a can, hang, or ursack. According to a backpacking light podcast, a nylofume (20x reduction) layered with an opsac (1000x reduction) would equal 20,000x reduction and make the smell range for a bear 10cm. 2 opsacs should be 1,000,000x smell reduction and eliminate the ability for a bear to detect the food. Also thinking about combining this method with an Adotec bag if I choose not to sleep with the layered odor bags.
I’ll relate my experience regarding layering of bags. I bought off Amazon a box of BOS odor sealing bags (X-Large) for diapers. I use them to double bag my food before I put it in my food bag or canister. My accidental test of their efficiency happened when I parked at a trailhead to hike into the Wind River Range. You are cautioned to not leave fresh, smelly food in your auto due to the risk of bears breaking into it. I had an orange a a very few other items which I put inside one bag and then used a twist tie to close it. I think a properly folded and twisted top bag closed with a twist tie or something similar seals in odors better than a ziplock bag. I then placed this bag inside a second one and closed the top with another twist tie. I left the bag inside the cab of the truck out of the sun. When I returned to my truck five days later and opened it I smelled nothing that smelled like food even though it was quite worm inside the cab from the sun shining in along with a warm outside temperature, probably in the upper 60s as I recall. When I opened the first layer of the food bag to get that orange I wanted to eat out wafted the smell of warm citrus fruit, a very distinctive smell. When I opened the inner bag of course the odor was even greater. The orange was fine, just a little warm. Double sealing food in odor proof bags works.
@@wanttogo1958 Thanks for sharing that! I am confident that it would be okay to sleep with my food layered in two Smelly Proof bags plus 1-2 Nylofume. But I decided I didn't want to risk the chance that a bear could still smell it so I ordered an Adotec bag. Still going to layer odor bags inside the Adotec, and still going to save 1.5 lb!
Great to know that you will still be diving in this subject. Very curious to know if a "caldera cone style" windscreen would dominate the wind category (and even with no wind due to concentrating heat)
While true all of these show really a "chimney" design which keeps the cross-wind reduced and forces heat up hugging the pan is the most efficient and in more conditions, you would struggle with a canister due to the heat of gas, and why they tend to be for ethanol which is a lower heat.
@@GearSkeptic Yes, that a valid concern depending on the room temperature. Maybe there is a length of cone that does not overheat the can so much while still providing heat concentration and wind protection for the pan (a HX might not be even needed). Perhaps using a shorter cone that does not touch the ground (or the top part of the two-piece system)
I've read that the canister should not exceed 125⁰F, though I do not knot if going somewhat above that is really a concern. A second probe (thermocouple) attached to the side of the canister might attest to that
This has me very interested in the ocelot mini. I like making hot drinks on trail so a mini-can only gets me ~3 days on trail comfortably, it would be great to push that further. But on the reverse having a bigger fuel can in the pack is a good “insurance policy”
Break this down for me. You go through 100g fuel canisters in 3 days? How many times do you use it per day? Under what conditions? I'm trying to wrap my head around this since typical lifespan is around 15-20 boils.
I suspect the variation you see in refilled canisters is that the initial fuel is not pure isobutane which would be very expensive for a manufacturer to produce. When the impure isobutane is used whichever components have the higher vapor pressure escape at a preferential rate, thereby enhancing the concentration of the lower vapor pressure compounds in the remaining fuel. When partially used canisters are combined you now have a fuel that has a lower vapor pressure than the new canisters and burns at a slower rate. This is more likely than changes in the valve.
Why would combining them lower the ratio beyond what was in the donor cans at the time of transfer? If I pour 4 cans of 90/10 gas mix into one container, I’d still have 90/10 mix, just four times as much.
Combining them would not change the average composition. Rather the now full combined/refilled canister would probably have a lower vapor pressure than a newly purchased canister that was still mostly full and thus would produce a lower flame when used on high. This would be easy to check. With a pure gas, at constant temperature, the vapor pressure and thus max burn rate should not change until it gets nearly empty. Measure the static pressure from a can at 80% full and 20% full; if its not the same at constant temperature then the composition of the starting gas is impure and thus changes in vapor pressure will affect your experiments as can empty.
@@jacksmack2382 That is what I am getting at. I have literally done that test hundreds of times. A canister at 20% performs exactly like one at 80%. At least, after having been used in the temperature of my shop. So, simply using four cans that were at 20% to fill an empty one to 80% should perform just like they were at 20% when transferred. Instead, I get this pronounced step change in performance, that does not seem explainable by differential burn. The refilling process itself won’t preferentially transfer one gas over another. They mix well and will keep the same ratio when in liquid, which is what transfers because the donor can is upside down during the exchange.
Ive had some old cans laying around for years, in my backup kit, I recently used them to light some fires with one of my stoves, they both clogged two stoves. Idk if its dirt that got into the valve surface or like rust inside the can ?? but now my one stove refuses to work at all. just very strange.
Thank you for detailed tests, but I didn't get answer to my question from the beginning - does it make sense to use BRS with petrel instead of Windmaster? It will slip inside the same way, but BRS is not only much lighter, but much more compact than windmaster as well.
The BRS has a flame that is completely unprotected. The Windmaster has a shroud that tucks into the heat exchanger ring for some combined protection. Expect the BRS to perform noticeably worse in the wind. You will have to prioritize weight versus fuel efficiency.
Could the change of flow rate come from a change of the gas mixture due to high vapor pressure gases evaporating first, leaving more low pressure gas in the mix after a refill?
I don’t think so. The reason is, the canisters (before refilling) show no change in performance. Just the act of pouring the leftovers into a new can would have no effect on the mixture. So, the refill should perform the same as the low canisters used to make it, but instead I get this pronounced step change in performance immediately after the refill process. Differential burn off should be a gradual, on going effect. My test temperature is well above the vaporization level of all gasses in the mix.
Great video, very interesting. Do you think the refilled can difference is because the propane iso butane blend changes as a can empties? Iso Butane and propane have different vapour pressures and calorific values. So towards the end of a cylinder the proportion of lower vapour pressures, high energy propane maybe less, reducing performance. Just a thought. Single gas rather than blended gases could be more predictable. Enjoy your videos to the last minute!
It’s an interesting idea. But, at my shop temperature, both gasses in the mix should be vaporizing strongly. There would still theoretically be a differential burn rate, but nothing like what it would be if I were below freezing.
Live and learn, another fuel canister we’ll burn 😅. Great work ! Perhaps stove system prices play into one’s decision as well. I guess more research is needed.
Something I'm curious about, is how a conical type, larger windscreen made of Al and mirror polished (to reflect IR efficiently) might affect efficiency? Another one is how flattened out heat pipes on the bottom but coming up on the sides would affect things?
Always plenty of usefull data. BUT I realized you kept the neoprene on the Micromo, (because it is standard to that pot I suppose). From what I have learned from all the previous videos, that would be an advantage compare to the other pot to prevent heat loss, especially with the wind. I would be curious to know how much does that neoprene weight, is it helping to protect against the wind or not. If yes, what is the advantage gr/boil of it. Would it be more efficient weight wise to discard the neoprene and trade it for a windscreen. So many questions and only one man to rule them all :P Thanks for your video Mr GearSkeptic
isobutane stove canisters use a mix of butane, isobutane, and propane. is it possible that repeated uses has preferentially boiled off the propane and isobutane leaving a mostly butane gas mix, and that the changed gas mix is responsible for your high flow anomaly? Like, with a low vapour pressure some fixed component may be acting as a restriction to flow, but at higher vapour pressures and lower flame settings the throttle valve becomes the primary restriction? could investigate by measuring the vapour pressure of the refilled bottles vs summer mix, winter mix, and straight butane from a lighter refill, and refilling a suspect canister with fresh fuel, and then comparing burn rates with a few different combinations of adapters and flame settings. might not be particularily useful, but could be interesting to investigate. maybe incorporate into a discussion on fuel selection and weather?
Interesting idea, but my shop is well above vaporization temperature for all gasses in the mix. From what I’ve read, it becomes a problem when it gets so cold that only propane can still vaporize. You lose that and end up with the stuff left over. But, that is a whole lot colder.
@GearSkeptic oh, it's absolutely an issue at low temperatures. But is it possible that something is causing it to occur at room temperature as well, just at a less pronounced rate so it only becomes an issue at very low canister volumes? My at best college level grasp of thermodynamics isn't enough to have any idea what that effect may be, but I personally doubt that the canister valve is damaged in a way that restricts flow but doesn't affect the usability in any other way. While the valve could absolutely have been damaged by the refill, unless your adapter is out of specification there's nothing about a normal refill adapter that should cause damage. It's simply two Lindal coupling back to back.
Others have suggested this, as well. It intrigues me, but the differential burn issue is one that comes into play more when the temperatures are below freezing. My shop (50F) is plenty warm enough to have even the isobutane boiling enthusiastically inside the can. If that was an issue (at my temps), it would manifest in the original can as it got close to empty. It wouldn’t be a refill issue, per se (in liquid form, the two gasses mix evenly, they don’t separate).
I've been wondering if there was a way to DIY a heat exchanger and if it would be as fuel and mass efficient as a commercially made pot with an HX built-in. I wonder how heavy it would need to be, or if thin metal fins would move heat fast enough on low. I'm guessing there are physics formulae that could predict that. I look forward to your craftiness.
It's possible, there's some cool stuff out there in the MYOG (make your own gear) community. The cooler stuff is carried deep in BPL, but its there. I've made a number of HX pots myself too, though they are very unconventional in a lot of ways and the heavy use of 3D printing may make some people feel like it's not true DIY. Lightest one I got so far way 68 grams for 550ml and has the efficiency just slightly below a jetboil stash, but performs much better in the wind thanks to a custom windscreen/arm 2-1 combo I made for the BRS3000T.
How much does having insulation around the pot (micromo) impact the boil time? It seems like that would reduce heat loss from the sides increasing efficiency. I would have liked to see the test with the insulation off. I believe the added weight would be worth the efficiency gain but I have not tested this theory myself.
I may have to do some controlled testing of cozies. Lids make far less difference than usually expected. Not sure how much the sides of the pot would matter, though it would go up the colder it was (and the stronger the wind).
@@GearSkeptic Right, the wind in particular is what made me think about it for this test. Convection heat loss may be significant. There is a cozy I have seen for the petrel that I would like to get and test boil time with and without. Then compare to the micromo to get a better 1:1 comparison. The micromo and stash are so similar in performance even though the micromo should be at a disadvantage due to the more narrow design, it makes me think the cozy may be a significant contributor to fuel efficiency. Just a theory though.
@@GearSkeptic Beat me to it, nice. For anyone wondering, neoprene sleeve improved a boil using about 1200 W of energy by about 40 W, so hardly at all. It's probably mostly useful for keeping food in the container from cooling down as quickly, not relevant at all if you are just boiling water for another vessel. ruclips.net/video/5h1eByFtzeg/видео.html
@ I did talk about this kind of heat loss a bit in the Wind Effects video. There, you see the wide pot (width is an advantage at 0 mph) eventually lose its place against narrower pots as the wind increases. I speculated this might have to do with the aspect ratio and the surface-to-volume issues of shape. If I am right and the extra surface area is why the wider pot eventually starts losing in strong wind, that would give you a glimpse as to what amount of fuel could be saved with a cozy to offset that loss (though only a percentage of it, since no cozy would be perfect).
I think is it less likely that refilling a fuel canister damaged the valve, more so I believe refilling a canister will result in less pressure inside compared to a brand new canister.
As long as there’s liquid inside, it means there is enough pressure to force the gasses into that state (which is more than enough to max out a stove).
Maybe an idea.. Measure how much weight the valves burn unrestricted by pots for a minute burn. If you ever need to readjust, do that again and it could give you a factor to apply to the new measurements?? Or build a rig to hook up compressed air and a manometer?
@@GearSkeptic maybe 3d printed aluminium then? I'm sure I once read that the ability to make titanium thinner offset the fact it was a poorer conductor relative to aluminium. Do you think that's actually true?
@@diceman9061 the problem is SLS beam width. I've made a number of 3D printed heat exchanger pots over the past 3 years. The limitation of the tech is beam width governing how thick your walls are. Currently the thinnest I can get titanium printed is 0.5mm and AL in 0.6mm because titanium is significantly heavier, the difference is t enough to offset the weight or efficiency saved by an AL HX. Maybe when the tech allows for much finer aspects ratio walls. But at the moment my experience has me eduacatedly guessing that AL is still better.
I hate to mention this ..... but have you considered that as all your testing is done with remote canister stoves it is possible, and in the wild very likely, that all of the stoves can/could be used with an enclosing circular wind shield. Certainly my preferred option in any windy or wintery conditions. Now you may think that this would simply re-align all the stoves back to the 'no-wind' results, but I think you and we may be surprised. Backpacking Stove Efficiency, Part 6 ? 😁
I avoid anything that would encourage somebody to enclose the gas canister within the heated area, as a potential safety risk. I did do a little bit about impromptu wind breaks, like using a backpack, tree, or available obstacle to help block wind. That can be found in Part 3 on windscreens, near the end at 34min11sec.
Can I offer an alternative hypothesis regarding the poor performance of the refilled can? Remember that gas canisters contain a mixture of gases with different boiling points, power outputs and, at a given temperature, different pressures in the can. Usually propane, isobutane, and n-butane. MSR IsoPro is 80/20 isobutane/propane. As you use the can, the different gases evaporate at different rates, with propane having a bias towards evaporating quickly. As the can nears empty, the propane may be almost completely gone while n-butane and isobutane remains. At this point, the pressure in the can may get low enough that you notice performance degradation, perhaps such that the power output that the "high" reference requires cannot be delivered by the can anymore. Because this is about the gas mixture, combining the left overs from many canisters does not fix the problem, it only results in a can full of "slow" gas. As for why it's only noticeable with the high reference, my only hypothesis is that it is the only one to require the high pressure of a fresh can with original gas mixture, in other words exactly like you state in the video. To determine if this is a likely root cause, take a new can and use the refill adapter to move the gas to an old canister. If the old canister with fresh gas performs well, then that suggests that it is indeed about the gas mixture. Otherwise, some kind of valve damage seems more likely.
That’s a good idea for a way to test it. I would point out, though, at my shop’s temperature even pure butane will vaporize easily and have more than enough pressure to max a small stove, so I don’t see how loss of propane would cause such a noticeable pressure drop. The remaining isobutane should be more than adequate by itself at 50F. It would be a very different story if you were so cold that the isobutane was having trouble boiling, but the propane wasn’t.
@GearSkeptic Yeah, I don't know if the effect is large enough to explain it at that temperature, like you say it should be (much) greater near the boiling point of the isobutane.
I am torn between having appreciation for the helpfulness and insight of your data, and awe for the thoroughness of your testing..... and wanting to tell you that you have too much time on your hands and you need to go out and get a life. Thank you for some truly awesome videos!
Graham Phobic has quite the head of hair, you know. Probably more than 150 grams. Perhaps he should consider getting a haircut before his next hike, for extra ✨lightness✨
You know you might be too deep on the rabbit hole when you hear "Testing of different material pots for heat efficiency" in the shower and exclaim out loud: "Oh, that one is going to be good." At the end of part 27, or whenever this ends at this pace, I fully expect an announcement of a GearSkeptic branded cook kit. It would be a shame to have all the data of what makes a good design, efficient, wind resistant, proper material and lighweight system and do nothing with it.
I’ll just take my Qiwiz Firefly UL twig stove at 79 grams and a few firelighters at reasonably under 50 grams and a lighter 15 grams and be happy with cooking/boiling in about 5 minutes with practice.
Thank you so much for all your efforts! You mentioned you don't know how people watch all the way through. I think a large part of it is your passion and attention to detail for the work shines through in the video. Its very satisfying to watch someone take a question like this to its logical conclusion and collect the best data possible.
Thank you! Most kind, and very much appreciated!
This kind of content, I generally prefer to have documented in white papers, where I can read through them, but fire, in particular, it's good to see/hear the various conditions, which cannot be properly communicated through text and pictures.
Dude just comes back and continues a series after not being here for nine months. That's a long hike!
Exactly ! Our boy pops into my notifications after forever and gives us more solid gold. LFG !!
But man is it worth it. This series is so valuable , at least to me
I think his shop has heat but no AC... And he does like to keep things consistent
@@allwaysareup That and he likes to backpack when seasons are good for that. Probably...
@@tcvalentine jokes on you, he is chained to his shop
You don’t know how we watch this all the way through? Duuude!! I’ve watched Performance Nutrition for Backpackers Series MULTIPLE times! Great information!!
Another outstanding series, and yes optimal configuration depends upon knowing your camping conditions. Number of boils per trip, wind conditions and understanding your stove all are important factors. Keep up the outstanding work!
Thanks! I should get at least one more batch of testing done before I lose the weather.
@@GearSkeptic The test matrix may become waaaaay too big, but it would be interesting to test alternate ways to increase efficiency on the pot end. I know you looked at lids vs. no lids a while ago. I think on that video I mentioned using a stretchy silicone lid as a way to prevent boil off as opposed to a metal lid. They can be bought in tons of sizes for very little on amazon. They also have the nice benefit of providing a visual cue when the water is close to a boil. By the time enough water has evaporated to stretch the lid off the water should be up to temperature.
The other thing I had in mind was a pot coozie to reduce heat loss to the environment. I'm very curious if that would make any measurable difference in either wind/no wind conditions.
@ I did buy silicone lids per your previous suggestion! That could maybe be tested together with cozies in a future installment 🤔
@@GearSkeptic awesome! Have you tried them out? I really like using mine in the field.
@ not yet!
Two additional observations:
1) This totally trounces all of those gear review RUclipsrs who got free Jetboil Stashes, shot wonky boil test videos and concluded it was an amazing system.
2) This video hit at the top of my feed after months since your last post. The algorithm does not appear to prioritize post frequency!
And all those tags are going to give me nightmares for weeks.
The Stash is an amazing system. It's a commercial ultralight pot and stove with incredible efficiency (primarily thanks to the great pot). Prior to the Stash people had to cobble something together out of various components which most hikers, and certainly most new hikers, wouldn't do. The Stash made a highly efficient and very light system available to all.
@ It’s an ok (although expensive) system. But as Gear Skeptic’s testing proves, it is not efficient in any kind of wind. It’s too bad, because the pot is solid, but the stove is the weak point.
If JetBoil offered the Stash pot as a separate component then they would see why people buy that system. It’s very expensive for what it is. Adding a removable wind screen might make it a better system for all wind conditions.
Bravo on keeping up the high scientific standard. Must be frustrating with the high flame issue. It’s incredible how much effort goes into, but really makes me rethink the stove/pot combo I’ve been using. For that I’m grateful.
Once again, EXCELLENT video! Your testing methods are far better than any other testing I have seen on youtube, for stoves. Regarding the issue of the refilled canister causing issues. I have been refilling canisters for many years. Canisters are filled with up to 3 different gasses. Butane, IsoButane and Propane. In the canister, the butane is typically on the bottom of the canister, with the propane typically in gaseous form on top. This is specifically why some canister stoves are designed for the canister to be upside down. This enables the higher pressure propane gas to push the butane (or isobutane) out first, making your stove burn better in lower temps longer.
Regarding your tests, when you refilled the canisters, if you heated the canister you want to drain, then connected the two canisters together via the valve, then opened up the valve, with the canister to drain upside down on top, you probably filled the canister you are trying to fill with mostly butane (or isobutane). Butane does not generate as much pressure and therefore will not push gas out as forcefully as a new canister, because of the lower amount of propane remaining in the cylinder. This also could explain your pressure loss issue.
FYI, this type of canister works very well when refilled with 80% by weight butane, then 20% propane. I've been doing this for many years and have never had any issues either in refilling or in usage. I've seen people have their nearly new canister valve completely go nuts (probably from foreign contaminants in the valve) when screwed in and completely drain after removing from the stove.
Interesting ideas. My shop is well above vaporization temp for all gasses, though. Also, I did not transfer just a portion of what remained. I emptied them. Did not use heat, just gave it as long as it needed.
@@GearSkeptic Is it possible you previously experienced some selective evaporation with the (original) canisters, altering the ratio of propane to butane remaining in them?
@@GearSkeptic Wouldn't there naturally be higher pressure in the lower canister? Wouldn't that lower canister be filled with the most liquified gas (butane), and the propane would float to the top, being the upper canister. I'm pretty sure you ended up with the upper cylinder containing some propane and all the butane/isobutane in the lower one.
Theoretically, there can be a difference in the burn off rate of the two gasses. But, that is something likely to only be noticeable if it is so cold that you are near the latent heat of vaporization for one of them. Then the differential will be greater. But, at my shop temperature, both gasses will be at the equivalent of a “rolling boil” inside the can. So, there won’t be a difference that would be so pronounced as to account for the difference in rate I saw.
As for the transfer process, it is done with the donating can upside down, so it is the liquid in question. Isobutane and propane share the same molecular bonding traits. They mix well and stay mixed to the end. While differential gas burn is at least a theoretical issue, pouring one liquid off the other isn’t.
Think of it this way: if the differential burn was that strong, you would have the same problem in the canister burned down. It wouldn’t matter whether you had refilled or not. All partially-consumed canisters would end up this way. From many, many measurements, I just don’t see that happening. At least at my temperature of testing. It would interesting to see what happens when running a stove at 15F.
@@GearSkeptic I'm pretty sure the key reason Propane is added to this mix is because per weight, Propane adds more pressure to the tank. That pressure is what pushes the gas out, what makes butane actually work at all below freezing. I believe your refilled canisters do not have enough propane in them. I have absolutely NO idea how much would need to be added and therefore, suggest just using them for non-essential or critical uses. They'd be great for weekend uses, but unless you completely empty the canisters and add butane and propane by weight, you'll never really know what the ratio in those refilled canisters is... Unfortunately, this means you're stuck with requiring brand new canisters, or identically refilled ones that were emptied and refilled with strict adherence to the ratio...
holy sht, GOAT
Mutton 😉
Glad to see you back! Most informative series on RUclips ever! Thank you for all the analysis you do.
@@turtlestampede3907 much appreciated!
Damn he's alive. I've watched through all of the Performance nutrition series the last week. I've applied all of that yesterday and I didn't return half dead after 8 hours of hiking. My problem before was drinking only water. Since I've started a year ago, I've been meticulously taking notes after every hike about any problem, feeling or consequence and improving my gear and nutrition based upon those observations. My goal is to lenghten the time I can spend outdoors in any conditions. The videos of Performance nutrition for hikers should be mandatory knownledge for any hiker, not allowed to leave the house without it.
Hydration knowledge and skills/experience are the real “10 essentials”
Very glad to hear it! Sharing what worked there for me is basically what started the channel 👍🏼
Wooooo!!!! Most anticipated video of the last 6 months
The tag joke got me good
That sucks about the valve degradation, appreciate you retesting all of that, that's a serious amount of work
Thank you for another well crafted, informative and unbiased video. I was very excited to see the latest installment. Watching the entire video was not a problem considering the cost of admission. I’m probably not going to be buying an HX pot anytime soon but the information you provided will stay in my back pocket.
I really appreciate the videos and the analysis. Your food spreadsheet changed the entire way I pack and hike in the backcountry.
Thanks! I am very glad to help.
Finally another video 😀 Please keep going and make more, go deeper and deeper into equipment, food, clothing, etc. Your work has helped me a lot in choosing the things I cary outdoors 👍👍
LETS GOOOOOOOOO, IM SO GLAD YOURE BACK
27:30 hahaha, you got quite the chuckle out of me with that one! Youve been elivated to UL GOAT!!!
Thanks for all the hard work. I love your test videos.
Always egerly look forward to your investigations. It's been a while, but that twist with the high rate valve conundrum made it worth the wait. Elements that used to make my old job fun. Nice tale, well told as always. Many thanks.👍👍👍
Very good as always. One thing that surprised the heck out of me was when I hiked in Ireland. I grabbed the same canister size I usually get and went out hiking. Two weeks later I was still on the same can. I cooked the same amount as normal, but the cans I got over there lasted me on average double what I got in the States. I ended up talking about it with a guy at one of the outfitters there. He said it's because the fuel they use there is mixed for near sea level. He said he doubted it would even work over 5000 feet. So that was a surprise.
Interesting. I do want to test fuel brands against each other eventually, including so-called “winter mixes” if I can find any.
@@GearSkeptic I just had a thought and checked the Dublin store. Turns out the stuff I used uses a 70/30 mix. The US fuels (MSR, Jetboil, and the like) use a 80/20 mix.
@@toocleanpappas5397 The more propane in the mix, the higher the canister pressure. The higher the pressure, the higher the risk of the canister rupturing, god forbid, if its next to a flame... I have tested refilling to 75/25 ratio, but don't think I would attempt going 70/30 unless I knew the canister had held that pressure previously... What brand of canisters were those you used with that ratio? THAT is the information that would be great to know...
Absolutely 💯 thrilled to see the next instalment in this series come out, immediate stop what you’re doing and press play!
I am not an ultralight hiker and take great comfort personally in knowing my MSR Reactor will perform in just about any conditions, i thoroughly enjoyed your meticulous attention to detail in this video. Thank you Sincerely from Australia 🇦🇺
That's a nice story but the retailer you were talking to is clueless. Canister pressure effectively increases for all pressure vessels as you gain altitude because the air is thinner. There is LESS force fighting the escaping gas so canisters work better in terms of fuel flow. The counter is your water also boils faster at a lower temp so it takes a bit longer to cook food.
Outstanding work, again! We watch all the way through because you are thorough, unbiased, and take a scientific approach. I use a Zip, Minimo or Trangia 27 (with Storm gas burner) depending on my trip. My informal tests show my Trangia 27 (at medium flame) to be slightly higher in gas consumption but not much in it. I know the Trangia system is less popular in USA than Europe, and it isn't for the weight conscious, but I'd love to see you put a Trangia 27 + Storm burner though it's paces!
I do (eventually) have plans to test alcohol stoves and compare their weight efficiency to canisters 👍🏼
Ah..For me alcohol stoves don't make sense: riskier to use near a tent, and my fuel usage makes has a no brainer from a weight/efficiency perspective. Trangia 27 started as an alcohol stove but the Storm gas burner gives the stove a different set of advantages. Cheers from UK!
Thank you for your in depth analysis and dedication !!!
I find all your videos just fascinating. Thank you for a new one.🎉🥰
@@TopazFarmerTravels you are always welcome!
Thanks for all your work on this, it's bugged me for ages whether it's worth the extra weight to carry my reactor. I was thinking, i need to plug this data into a spreadsheet so I know when it's worth bringing, then if course you say you've already done this and made it available for download. You're a legend. And I'll watch any video you put out in full, sometimes a second time because it didn't all sink in the first time
I've been anticipating this video. Great information, as always!
you're a rare individual with an inquiring mind - dankie!
Dang, another fantastic presentation! While you’ve made the point that there is no perfect system, I’m happy to have my titanium pot and tiny lightweight burner! I do all my boiling behind my vestibule with minimal wind.
Hey! Glad you are back! Hope the roof is all good now!
Thanks! It’s holding, pending full repair when the snow melts off.
As always, an amazing video with amazing detail. I appreciate this level of detail so much.
Aways excellent Mr Skeptic. Although the camera view of the desk grid is misaligned. Noticed it 4 minutes in... CAN'T UNSEE!! 🤣
😱
@@GearSkeptic However, all your data collection and analysis is bang on, thank you for all the time & effort you put into these.
I've noticed my cannister refills seem to be a little weaker at WOT also...wonder if that's a potential point of failure over time?
Yah, it happened to me with two cans in a row.
@@GearSkeptic I posted a reply above about this, but I suspect when you refilled, you put the old canisters butane (low pressure) into the canister you were refilling. The propane usually stays in its gaseous state, whereas the butane is mostly a liquid. That means the propane stayed in the canister after you thought it was empty... Refilling canisters isn't realistically supposed to make the canister as good as a brand new one. It's just supposed to make a canister that works without buying a new one...
That got me too!
Excellent video. Appreciate the effort you put into these tests. I've some experience trying to get consistent and repeatable results testing consumer level equipment (not stoves) that aren't designed with exact adjustments as a priority. I know it can be extremely time consuming and frustrating which makes your videos even more impressive.
I've owned/own 5-6 stoves so can to some extent pick the one that's most suited of a specific trip, but if I had to choose one that should work for all types trips I've done then fuel efficiency and stove + fuel weight (while certainly important) wouldn't be my top priority. Fuel availability, performance in cold and stability of the stove is even more important to me.
Much awaited ep. Thanks & Cheers!
36:19 From one engineer to another:
This effect is called stiction and it is common in control valves in industrial controls where fine tuning is of critical importance. The creep effect is also why industrial controls now use valve positioners, which keep valves at their set positions.
Probably not very interesting to many, but it's completely common to those in that world.
In the end of that series we will get to an integrated can-stove-pot with only 50 grams overhead on top of the fuel weight and burning efficiency of 3.2g/boil in any wind condition.
Looking forward to comparing the Petrel G3 Vs Petrel G2 😇
Think you mean G2 Vs G3
@iwalker3809 🙈 you are absolutely right 👍 I've corrected it
Glad you’re back!
Sorry for your inconvenience, but learning that refueling a canister can damage the valve and effectively cap the output is very useful information.
I’ve never heard mention of it before, and makes me realize I should probably stop refilling the same canister I’ve filled 4 times now.
True but if you've got a wide pot....
I’ve had one other problem with a refill that was an off-brand small can. That one just causes the stove to geyser up flame uncontrollably. Not safe to use any more. It is making me want to avoid refilling, but some people say they’ve done it for years without (noticing) issues.
@@GearSkeptic okay well I’m definitely going to start testing refills before taking them on a trip now at least, that’s terrifying
Hysteresis; bummer, man. I appreciate your videos immensely.
Love the videos man. Two things, first I just keep tin foil nested in my pot and open it up as a windscreen, works for me. Second, and something I've searched for answers and none have the skills like you to dive deep into...stakes. Shape, length, angle, V Y Shepard hook, which direction the V is in, we must find out.
Oh, I have a large collection of stakes. It!s on the list 👍🏼
@@GearSkeptic That's because you're a hero.
One other related thing I would be interested in seeing you test would be how temperature affects these stoves, and perhaps even some methods to mitigate the tendency for Iso canisters to freeze up in the cold.
@@mikekraut7643 yah, I’ve thought about extreme cold weather testing. Be tough, though. It’d have to be outside, and then controlling the environment would be hard. Also, the opportunities are rare for that.
Will need to wait for more testing. I may need to do some testing of my own before spring.
Excellent video as usual. Thank you for your efforts!
You are welcome!
Oh Great & Powerful OZ !
You have arrived form the skies, prophesied to save us with Skeptic Enlightenment !
Your dedication and rigour is quite simply extraordinary. Thank you not only for your efforts, but also for achieving your aim of demonstrating a methodology for others to examine any given question.
If it means anything, I have just watched all five episodes in this series back to back. Odd as I may be, it has been a genuinely fascinating and enjoyable experience.
I do have one question which might affect a “best system” decision: how many boils do you actually get out of a canister? My experience is that you never actually utilise the full amount. Might this mean that the lighter systems lose out even for shorter trips? I will attempt to work that out myself, but hope that it’s worth raising for consideration.
Interesting. I never do run the can down to where the stove actually dwindles out. I suppose I should try it, then weigh in to see how much fuel might still be left.
@@GearSkepticHopefully some of the part used canisters are still around from all of the testing.
Thank you again for all you do.
Matt Shafter is the Alton Brown of Ultralight, but my man here is Bob Ross meets Werner Van Braun meets Darwin . Nobody better
Too kind, but appreciated!
thanks. keep going. a pleasure to see that next part .)
Love your videos! Keep it up
I was just revisiting your videos a couple days ago!
Outstanding!
I also would love to have you do a video on radiative stoves like the MSR reactor and others
YES!!! ANOTHER GEAR SKEPTIC!!
Fantastic! Thank you so much for the tremendous effort and time put into these videos! The revelation that ha refill valve maybe damaging a cans output is also shocking. Will you be doing more testing in this with different valves?
Well, I do have another experience with refill of a small can, off brand. That one causes the flame to just geyser up from the stove like a jet engine exhaust. Unusably dangerous. A different kind of failure, though.
oh man your error had to have been supremely frustrating. Still, you have one of the most stringent testing methodologies I have seen in this space so feel too bad, you are still far more accurate and useful that anyone else I know in these test. have you ever though of setting up a wishlist for the gear you want to test or patreon, not sponsored but from your viewers. I would imagine that you would be able to have many people who would appreciate being able to help you defray some of the cost.
Very kind, but no need!
Great, new video!
Love this series as a data nerd. As another baseline, how about testing a basic UL pot/stove combo with an external, unattached windscreen. Like some thin foil cylinders, or I use a piece of kitchen aluminum foil folded a couple times, that rests on the ground and leans up against the pot, covering roughly the upwind 1/2, but still plenty of space to keep the can cool
I did a few impromptu wind break tests for the wind effects episode. I avoided the exterior, free-standing kind because those also encapsulate the canister. Don’t want to get involved in a strategy that might encourage someone to overheat their can.
@@GearSkeptic Fair enough. Any hint as to what your impromptu testing showed?
@ check out Part 3 on windscreens. You can jump to the end at 34min11sec, from the index: Tiered Wind Protection.
Of course we watch the full video! I'm at the edge of my seat to learn the answer to: what if...?
I'm currently using mostly alcohol and the brs, but I do like how the HX systems have such stable fuel consumption in comparison. This would make planning much easier. But as you already talked about in the previous part, it makes only sense if I can go lighter on the can I use. The smallest can I can regularly my hand on is the medium/410ml/230g size. For a weekend hiker, I will probably never empty one in one trip.
But perhaps I can check, if I can get some stable fuel use with the alcohol burner. At the moment it is a hard-to-make rough guess every time how much alcohol I need to put into the burner. Which I often don't get back when I guessed to much and becomes really "scary" if have to refuel, because there could be still a hidden flame. Here the more stable fuel usage would give me a reason to accept more weight and bulk of an HX system.
Why not a Trangia burner or similar?
Excellent!
Wooooooooooooooo! Love it!
Haha YES, HE IS BACK !!!!! The dark days are over.
Found your channel recently and boy is it a gold mine! Would like to eventually see a video about odor resistant bags like nylofume; opsac, smelly proof, etc. Specifically, I'm wondering if I could layer them to eliminate the smell and not have to use a can, hang, or ursack. According to a backpacking light podcast, a nylofume (20x reduction) layered with an opsac (1000x reduction) would equal 20,000x reduction and make the smell range for a bear 10cm. 2 opsacs should be 1,000,000x smell reduction and eliminate the ability for a bear to detect the food. Also thinking about combining this method with an Adotec bag if I choose not to sleep with the layered odor bags.
I’ll relate my experience regarding layering of bags. I bought off Amazon a box of BOS odor sealing bags (X-Large) for diapers. I use them to double bag my food before I put it in my food bag or canister. My accidental test of their efficiency happened when I parked at a trailhead to hike into the Wind River Range. You are cautioned to not leave fresh, smelly food in your auto due to the risk of bears breaking into it. I had an orange a a very few other items which I put inside one bag and then used a twist tie to close it. I think a properly folded and twisted top bag closed with a twist tie or something similar seals in odors better than a ziplock bag. I then placed this bag inside a second one and closed the top with another twist tie. I left the bag inside the cab of the truck out of the sun. When I returned to my truck five days later and opened it I smelled nothing that smelled like food even though it was quite worm inside the cab from the sun shining in along with a warm outside temperature, probably in the upper 60s as I recall. When I opened the first layer of the food bag to get that orange I wanted to eat out wafted the smell of warm citrus fruit, a very distinctive smell. When I opened the inner bag of course the odor was even greater. The orange was fine, just a little warm. Double sealing food in odor proof bags works.
@@wanttogo1958 Thanks for sharing that! I am confident that it would be okay to sleep with my food layered in two Smelly Proof bags plus 1-2 Nylofume. But I decided I didn't want to risk the chance that a bear could still smell it so I ordered an Adotec bag. Still going to layer odor bags inside the Adotec, and still going to save 1.5 lb!
You really did a great job😮😮😮😮😮😮😮
Great to know that you will still be diving in this subject. Very curious to know if a "caldera cone style" windscreen would dominate the wind category (and even with no wind due to concentrating heat)
While true all of these show really a "chimney" design which keeps the cross-wind reduced and forces heat up hugging the pan is the most efficient and in more conditions, you would struggle with a canister due to the heat of gas, and why they tend to be for ethanol which is a lower heat.
I have a caldera cone for an alcohol stove. Gotta be careful about not creating an “oven” that would dangerously overheat a gas canister.
@@GearSkeptic Yes, that a valid concern depending on the room temperature. Maybe there is a length of cone that does not overheat the can so much while still providing heat concentration and wind protection for the pan (a HX might not be even needed). Perhaps using a shorter cone that does not touch the ground (or the top part of the two-piece system)
I've read that the canister should not exceed 125⁰F, though I do not knot if going somewhat above that is really a concern. A second probe (thermocouple) attached to the side of the canister might attest to that
thank you
@@saegmam you are welcome!
This has me very interested in the ocelot mini. I like making hot drinks on trail so a mini-can only gets me ~3 days on trail comfortably, it would be great to push that further. But on the reverse having a bigger fuel can in the pack is a good “insurance policy”
Break this down for me. You go through 100g fuel canisters in 3 days? How many times do you use it per day? Under what conditions? I'm trying to wrap my head around this since typical lifespan is around 15-20 boils.
Awesome this is going to be great
I suspect the variation you see in refilled canisters is that the initial fuel is not pure isobutane which would be very expensive for a manufacturer to produce. When the impure isobutane is used whichever components have the higher vapor pressure escape at a preferential rate, thereby enhancing the concentration of the lower vapor pressure compounds in the remaining fuel. When partially used canisters are combined you now have a fuel that has a lower vapor pressure than the new canisters and burns at a slower rate. This is more likely than changes in the valve.
Why would combining them lower the ratio beyond what was in the donor cans at the time of transfer? If I pour 4 cans of 90/10 gas mix into one container, I’d still have 90/10 mix, just four times as much.
Combining them would not change the average composition. Rather the now full combined/refilled canister would probably have a lower vapor pressure than a newly purchased canister that was still mostly full and thus would produce a lower flame when used on high. This would be easy to check. With a pure gas, at constant temperature, the vapor pressure and thus max burn rate should not change until it gets nearly empty. Measure the static pressure from a can at 80% full and 20% full; if its not the same at constant temperature then the composition of the starting gas is impure and thus changes in vapor pressure will affect your experiments as can empty.
@@jacksmack2382 That is what I am getting at. I have literally done that test hundreds of times. A canister at 20% performs exactly like one at 80%. At least, after having been used in the temperature of my shop. So, simply using four cans that were at 20% to fill an empty one to 80% should perform just like they were at 20% when transferred. Instead, I get this pronounced step change in performance, that does not seem explainable by differential burn.
The refilling process itself won’t preferentially transfer one gas over another. They mix well and will keep the same ratio when in liquid, which is what transfers because the donor can is upside down during the exchange.
I Love You Man,..laughing with a mouthful of Eureka-sauce... thanks for pursuit of your science.
Ive had some old cans laying around for years, in my backup kit, I recently used them to light some fires with one of my stoves, they both clogged two stoves. Idk if its dirt that got into the valve surface or like rust inside the can ?? but now my one stove refuses to work at all. just very strange.
Thanks!
@@allwaysareup you are welcome!
Gear Sceptic!🥳🥰
I was worried that the most universally beloved figure in the backpacking community might stop uploading. I can't wait for the flashlight tests!
Thank you for detailed tests, but I didn't get answer to my question from the beginning - does it make sense to use BRS with petrel instead of Windmaster? It will slip inside the same way, but BRS is not only much lighter, but much more compact than windmaster as well.
The BRS has a flame that is completely unprotected. The Windmaster has a shroud that tucks into the heat exchanger ring for some combined protection. Expect the BRS to perform noticeably worse in the wind. You will have to prioritize weight versus fuel efficiency.
Could the change of flow rate come from a change of the gas mixture due to high vapor pressure gases evaporating first, leaving more low pressure gas in the mix after a refill?
I don’t think so. The reason is, the canisters (before refilling) show no change in performance. Just the act of pouring the leftovers into a new can would have no effect on the mixture. So, the refill should perform the same as the low canisters used to make it, but instead I get this pronounced step change in performance immediately after the refill process. Differential burn off should be a gradual, on going effect. My test temperature is well above the vaporization level of all gasses in the mix.
Great video, very interesting. Do you think the refilled can difference is because the propane iso butane blend changes as a can empties? Iso Butane and propane have different vapour pressures and calorific values. So towards the end of a cylinder the proportion of lower vapour pressures, high energy propane maybe less, reducing performance. Just a thought. Single gas rather than blended gases could be more predictable. Enjoy your videos to the last minute!
It’s an interesting idea. But, at my shop temperature, both gasses in the mix should be vaporizing strongly. There would still theoretically be a differential burn rate, but nothing like what it would be if I were below freezing.
Live and learn, another fuel canister we’ll burn 😅. Great work ! Perhaps stove system prices play into one’s decision as well. I guess more research is needed.
Something I'm curious about, is how a conical type, larger windscreen made of Al and mirror polished (to reflect IR efficiently) might affect efficiency?
Another one is how flattened out heat pipes on the bottom but coming up on the sides would affect things?
Interesting. That might exceed my crafting abilities at this time, though…
Always plenty of usefull data. BUT I realized you kept the neoprene on the Micromo, (because it is standard to that pot I suppose). From what I have learned from all the previous videos, that would be an advantage compare to the other pot to prevent heat loss, especially with the wind.
I would be curious to know how much does that neoprene weight, is it helping to protect against the wind or not. If yes, what is the advantage gr/boil of it. Would it be more efficient weight wise to discard the neoprene and trade it for a windscreen.
So many questions and only one man to rule them all :P
Thanks for your video Mr GearSkeptic
Yah, maybe pot cozies would be a topic for a future test. Sigh 😉
Quality!
Admittedly not a big weight saving, but it’d be interesting to compare the Petrel + Windmaster to Petrel + Hornet II
isobutane stove canisters use a mix of butane, isobutane, and propane. is it possible that repeated uses has preferentially boiled off the propane and isobutane leaving a mostly butane gas mix, and that the changed gas mix is responsible for your high flow anomaly? Like, with a low vapour pressure some fixed component may be acting as a restriction to flow, but at higher vapour pressures and lower flame settings the throttle valve becomes the primary restriction?
could investigate by measuring the vapour pressure of the refilled bottles vs summer mix, winter mix, and straight butane from a lighter refill, and refilling a suspect canister with fresh fuel, and then comparing burn rates with a few different combinations of adapters and flame settings. might not be particularily useful, but could be interesting to investigate. maybe incorporate into a discussion on fuel selection and weather?
Interesting idea, but my shop is well above vaporization temperature for all gasses in the mix. From what I’ve read, it becomes a problem when it gets so cold that only propane can still vaporize. You lose that and end up with the stuff left over. But, that is a whole lot colder.
@GearSkeptic oh, it's absolutely an issue at low temperatures. But is it possible that something is causing it to occur at room temperature as well, just at a less pronounced rate so it only becomes an issue at very low canister volumes?
My at best college level grasp of thermodynamics isn't enough to have any idea what that effect may be, but I personally doubt that the canister valve is damaged in a way that restricts flow but doesn't affect the usability in any other way. While the valve could absolutely have been damaged by the refill, unless your adapter is out of specification there's nothing about a normal refill adapter that should cause damage. It's simply two Lindal coupling back to back.
Others have suggested this, as well. It intrigues me, but the differential burn issue is one that comes into play more when the temperatures are below freezing. My shop (50F) is plenty warm enough to have even the isobutane boiling enthusiastically inside the can. If that was an issue (at my temps), it would manifest in the original can as it got close to empty. It wouldn’t be a refill issue, per se (in liquid form, the two gasses mix evenly, they don’t separate).
I've been wondering if there was a way to DIY a heat exchanger and if it would be as fuel and mass efficient as a commercially made pot with an HX built-in. I wonder how heavy it would need to be, or if thin metal fins would move heat fast enough on low. I'm guessing there are physics formulae that could predict that. I look forward to your craftiness.
It's possible, there's some cool stuff out there in the MYOG (make your own gear) community. The cooler stuff is carried deep in BPL, but its there. I've made a number of HX pots myself too, though they are very unconventional in a lot of ways and the heavy use of 3D printing may make some people feel like it's not true DIY.
Lightest one I got so far way 68 grams for 550ml and has the efficiency just slightly below a jetboil stash, but performs much better in the wind thanks to a custom windscreen/arm 2-1 combo I made for the BRS3000T.
How much does having insulation around the pot (micromo) impact the boil time? It seems like that would reduce heat loss from the sides increasing efficiency. I would have liked to see the test with the insulation off. I believe the added weight would be worth the efficiency gain but I have not tested this theory myself.
I may have to do some controlled testing of cozies. Lids make far less difference than usually expected. Not sure how much the sides of the pot would matter, though it would go up the colder it was (and the stronger the wind).
@@GearSkeptic Right, the wind in particular is what made me think about it for this test. Convection heat loss may be significant. There is a cozy I have seen for the petrel that I would like to get and test boil time with and without. Then compare to the micromo to get a better 1:1 comparison. The micromo and stash are so similar in performance even though the micromo should be at a disadvantage due to the more narrow design, it makes me think the cozy may be a significant contributor to fuel efficiency. Just a theory though.
@@Genesis-revelation70 Flat Cat Gear did some boil tests on the Petrel cozy. He has a video on it.
@@GearSkeptic Beat me to it, nice. For anyone wondering, neoprene sleeve improved a boil using about 1200 W of energy by about 40 W, so hardly at all. It's probably mostly useful for keeping food in the container from cooling down as quickly, not relevant at all if you are just boiling water for another vessel. ruclips.net/video/5h1eByFtzeg/видео.html
@ I did talk about this kind of heat loss a bit in the Wind Effects video. There, you see the wide pot (width is an advantage at 0 mph) eventually lose its place against narrower pots as the wind increases. I speculated this might have to do with the aspect ratio and the surface-to-volume issues of shape. If I am right and the extra surface area is why the wider pot eventually starts losing in strong wind, that would give you a glimpse as to what amount of fuel could be saved with a cozy to offset that loss (though only a percentage of it, since no cozy would be perfect).
👍👍👍
Woot!
Thanks! Ledgendery ❤
I think is it less likely that refilling a fuel canister damaged the valve, more so I believe refilling a canister will result in less pressure inside compared to a brand new canister.
As long as there’s liquid inside, it means there is enough pressure to force the gasses into that state (which is more than enough to max out a stove).
Maybe an idea.. Measure how much weight the valves burn unrestricted by pots for a minute burn. If you ever need to readjust, do that again and it could give you a factor to apply to the new measurements?? Or build a rig to hook up compressed air and a manometer?
I wonder when we'll see a heat exchanger that's made from 3d printed titanium? I bet there's some scope for improvement there...
In weight, perhaps, but titanium is a poor conductor of heat. So, efficiency of the exchanger would suffer.
@@GearSkeptic maybe 3d printed aluminium then? I'm sure I once read that the ability to make titanium thinner offset the fact it was a poorer conductor relative to aluminium. Do you think that's actually true?
@@diceman9061 the problem is SLS beam width. I've made a number of 3D printed heat exchanger pots over the past 3 years. The limitation of the tech is beam width governing how thick your walls are. Currently the thinnest I can get titanium printed is 0.5mm and AL in 0.6mm because titanium is significantly heavier, the difference is t enough to offset the weight or efficiency saved by an AL HX. Maybe when the tech allows for much finer aspects ratio walls. But at the moment my experience has me eduacatedly guessing that AL is still better.
Slam dunk!
🏀
I hate to mention this ..... but have you considered that as all your testing is done with remote canister stoves it is possible, and in the wild very likely, that all of the stoves can/could be used with an enclosing circular wind shield. Certainly my preferred option in any windy or wintery conditions. Now you may think that this would simply re-align all the stoves back to the 'no-wind' results, but I think you and we may be surprised. Backpacking Stove Efficiency, Part 6 ? 😁
I avoid anything that would encourage somebody to enclose the gas canister within the heated area, as a potential safety risk.
I did do a little bit about impromptu wind breaks, like using a backpack, tree, or available obstacle to help block wind. That can be found in Part 3 on windscreens, near the end at 34min11sec.
@@GearSkeptic You misunderstood - the canister is 'remote' so would NOT be enclosed, just the stove
@@OldBlindMole oh, right you are. I do have some remote stoves and would like to do such testing. I don’t know about Part 6, but it is on the list!
Can I offer an alternative hypothesis regarding the poor performance of the refilled can?
Remember that gas canisters contain a mixture of gases with different boiling points, power outputs and, at a given temperature, different pressures in the can. Usually propane, isobutane, and n-butane. MSR IsoPro is 80/20 isobutane/propane. As you use the can, the different gases evaporate at different rates, with propane having a bias towards evaporating quickly. As the can nears empty, the propane may be almost completely gone while n-butane and isobutane remains. At this point, the pressure in the can may get low enough that you notice performance degradation, perhaps such that the power output that the "high" reference requires cannot be delivered by the can anymore.
Because this is about the gas mixture, combining the left overs from many canisters does not fix the problem, it only results in a can full of "slow" gas.
As for why it's only noticeable with the high reference, my only hypothesis is that it is the only one to require the high pressure of a fresh can with original gas mixture, in other words exactly like you state in the video.
To determine if this is a likely root cause, take a new can and use the refill adapter to move the gas to an old canister. If the old canister with fresh gas performs well, then that suggests that it is indeed about the gas mixture. Otherwise, some kind of valve damage seems more likely.
That’s a good idea for a way to test it. I would point out, though, at my shop’s temperature even pure butane will vaporize easily and have more than enough pressure to max a small stove, so I don’t see how loss of propane would cause such a noticeable pressure drop. The remaining isobutane should be more than adequate by itself at 50F. It would be a very different story if you were so cold that the isobutane was having trouble boiling, but the propane wasn’t.
@GearSkeptic Yeah, I don't know if the effect is large enough to explain it at that temperature, like you say it should be (much) greater near the boiling point of the isobutane.
I am torn between having appreciation for the helpfulness and insight of your data, and awe for the thoroughness of your testing..... and wanting to tell you that you have too much time on your hands and you need to go out and get a life. Thank you for some truly awesome videos!
Fair enough!
The clothes tag weigh in 🤣
😜
Tent should cut most of the wind.
You can eat outside if there is bear fear.
Just some thoughts of mine.
@21:22 hey, i resemble that remark
i love you
Holy tags batman!!
Graham Phobic has quite the head of hair, you know. Probably more than 150 grams. Perhaps he should consider getting a haircut before his next hike, for extra ✨lightness✨
And…he’d also save weight on shampoo.
You know you might be too deep on the rabbit hole when you hear "Testing of different material pots for heat efficiency" in the shower and exclaim out loud: "Oh, that one is going to be good."
At the end of part 27, or whenever this ends at this pace, I fully expect an announcement of a GearSkeptic branded cook kit. It would be a shame to have all the data of what makes a good design, efficient, wind resistant, proper material and lighweight system and do nothing with it.
Ha! The more I learn, the more it makes me want to tinker…
You sure wear a lot of clothes to cut weight ;)
I’ll just take my Qiwiz Firefly UL twig stove at 79 grams and a few firelighters at reasonably under 50 grams and a lighter 15 grams and be happy with cooking/boiling in about 5 minutes with practice.