Primus Micron Ti 2.5 Stove
I know a few hikers who say they can get by without warm food in the wild, even on long treks. Some like this approach because it saves some weight and time. I'm sure we could go stoveless for a couple of days, too. However, a warm meal is a warm meal, and if conditions permit, we really like to have at least one a day. Same goes for hot drinks, Em loves a hot cup of coffee in the morning, while I go for tea (quit coffee about 15 years ago). There's no question about it, most backpackers carry some kind of stove system. Which one is the best? Again, it boils (pun intended) down to the question of weight vs convenience and operating conditions. On our first two ultra-heavy trips we had a huge Coleman burner with a big 16.4 oz. gas canister. I'm not even going to get into how foolish that was. When gearing up (well, down) for the next generation of trips, we decided to stay with a canister system, though this time trying to find something much, much lighter.
Compared to all the other systems (alcohol, petroleum, fuel tablets, wood, etc.), canister stoves looked like the best choice as far as weight and operation goes, especially when taking into account the type of adventures we generally embark on. They are pretty easy to operate, the flame can be regulated well, their fuel choices offer a great energy-to-weight ratio, and (especially with a few tricks) they work OK in the temperature range we usually encounter, i.e. medium-hot to sub-freezing, but not arctic.
The most ancient method – making a wood fire – has huge drawbacks on a backpacking trip. First of all, wood fires are prohibited in many wilderness areas. In places too low in altitude because of the fire danger, in the desert and above certain elevations because is depletes the scarce resources. The little plant matter growing there is needed to replenish the nutrients in the soil.
Second, the time it takes to gather wood and get a fire going is sometimes prohibitive if you're tired after a long day's hike or you want to get going quickly in the morning. Then we didn't even talk about minor inconveniences, as scrubbing the soot off the pans, smoking up the precious backcountry equipment, etc. Also, we very strongly desagree with the philosophy to have a fire going in camp for no particular reason.
Tiny wood-burning stoves that use finger-thick pieces or scrap wood can be very practical in some circumstances, and a few are even high-tech with integrated electric fans and chargers (like the Biolite). However, I consider most of them impractical for backpacking.
One of the lightest systems are the small fold-up stoves, some for use with fuel tablets, some the above-mentioned wood-burning version.
Then there are alcohol stoves. The perennial favorite of thru-hikers, they are very, very light, it's very easy to find fuel for them (especially in the US), they're cheap to acquire and to operate and work pretty well in sub-freezing conditions. However, the fuel is heavy (alcohol has way less energy content than petroleum or propane/butane), and in most cases, the flame can't be regulated very well. All these disadvantages aside, they're the superior choice for ultralight, long distance hiking.
The Primus Micron Ti 2.5
After we decided on a canister stove, some more research went into finding the lightest one, and finally settled on the Primus Micron Ti 2.5. As its name suggests, it weighs 2.5 ounces and it's made mostly of titanium alloy. The heavier, more integrated systems like the Jetboil didn't appeal to us, mostly for the weight. They may be much easier to use in windy conditions, but I was confident we'll be able to handle this aspect.
The Ti 2.5 has three, tiny folding support arms that look pretty flimsy, but they click into place very firmly and support the pot very well. We used it for over 100 days, cooking at least a quart of water in the morning, another (sometimes two) in the evening, and now and then a soup during the day. The arm never bended or became unlocked. It still folds and unfolds like it's brand new.
It had a version with a piezoelectric igniter, but I opted for the one without, as it would only add another component that can break. We always have several way of creating a spark to light the stove, including a tiny piezoelectric spark assembly I salvaged from an empty single-use lighter.
Almost always, we use it with an Evernew titanium pot. The lower part is quart-sized with a pint-sized lid. This is one of the lightest pots available and fits the stove very well.
The canisters & freezing temperatures
Cartridges for this stove can be found in many shapes, sizes and brands. We usually buy the 8.9 oz. by Primus. With normal use, it lasts 5-6 days. For weeklong trips, we take a full and a half-empty one (we almost always have one of those around).
At low temperatures, if the gas can't reach its boiling point, the canister isn't under enough pressure to produce a sustained flame. It either sputters, or nothing happens at all. A great way to making it work is to put the bottom of the canister in in at least 1-1.5" water (the water doesn't have to be warm). This way, the gas will boil much easier and create adequate pressure.
The Primus four-season mix is great, we almost never had to resort to any tricks to get it going. The coldest we ever operated it was in around 26° F at 11,000' (lower air pressure actually mitigates some ill effects of low temperatures, but of course adds cooking time because of decreased efficiency). The canister was stored in the tent overnight and had no trouble cooking tea in the morning.
However, one time at Sespe Hot Springs, only at 5,000', the canister was left outside, and it was around 30° F when we started cooking. It sputtered like crazy, but a few seconds after we put the canister in water, it worked like a charm.
The aforementioned 8.9 oz. canister is pretty wide, so it gives relatively OK stability to the whole setup when the titanium pot is full of water (or food, or stones – more about that later). Of course, basic precautions need to be taken, and it's always a good idea to set it up in a place where you won't kick it while wandering around camp a bit dizzy from a combination of altitude, fatigue, hunger, and maybe the great scenery you saw that day.
This is an unregulated stove, meaning the gas flows from the canister to the burner with the unmitigated pressure supplied by the canister itself. In most situations, this is perfectly fine. As the fuel quantity decreases, so does the pressure and thus the output, resulting in longer boil times. In practice this affects with last 2-3 times there’s fuel left, in the very end the flame is really tiny. Compared with how light and sturdy this stove is, we just live with it.
As a comparison, on a regulated stove, you’ll get full pressure until you’re almost completely out of gas. Of course, a regulated stove is always a bit heavier, but with advances in technology, even these are becoming a viable option. See the very end of this article for an update on our latest stove.
Well, there's no built-in wind protection here whatsoever. At 2.5 oz., how could there be?
Of course, if the system is in the open, even a light breeze can blow off enough heat to double the heating time and thus waste huge amounts of fuel. However, this doesn't have to happen. It almost always possible to find some windshade next to a rock, a tree or the tent (just watch what you're doing so nothing goes up in flames). A few times, we cooked without problems in 30+ mph winds by erecting a windshelter of smaller rocks next to a big rock. Sometimes, when the ground is soft enough, I dig a 5-6" hole and place the canister in it, increasing the efficiency of the windscreen.
Finding a decent spot sheltered from the wind is not always easy. Spots that look very protected can have a draft breezing through them, making it even worse. When I'm looking for a place to set up the oven, I walk around with a lighter, squatting in candidate spots, waiting for a gust of wind. Then I light the lighter, look at the small flame, and try to gauge how much that spot is protected compared to the other areas. Works pretty well. If your lighter's flame is being moved around, but not snuffed out, the stove will do great.
Mornings, we usually heat a full quart to make a small coffee for Em and some tea for both to share. The boiling time is around 5 minutes, but it can vary a lot depending on temperature and altitude. For dinner, we boil 12 ounces of water to rehydrate the food. This much comes to a boil in 3 minutes or less, then we dump the food in, wait another few seconds for it to come back to boil, put the lid on and then turn the heat off.
For cooking fish, we have a weird system, as frying would be prohibitive. I read about a version of this idea somewhere, then developed our own approach. First, we have to catch fish. That's a different story. So let's say there are a few small brookies or golden trout you usually encounter in the Sierra. I chop heads and tails off, clean them, then Em makes a nice package with soy sauce, spices and tabasco in thick aluminum foil (we carry a small sheet folded up with the Orikaso). In the meantime, I look for 5-6 small rocks, maybe somewhat smaller than a golf ball. I make sure they're relatively clean of dirt (or wash them in the stream), then arrange them in the bottom of the pan and add some water, covering the stones about halfway up. The foil package goes on top of this. The whole idea is for the boiling water not to touch the foil so it can steam nicely (steam is much hotter than boiling water).
Next the lid goes on and the pot is placed on the stove on high heat until the water starts to boil. Then I turn the heat down as much as I can, and let the whole thing simmer. Depending on altitude and the size of the fish, it takes 8-10 minutes for the steam to cook the fish. Honestly, it doesn't taste as nice as fish barbequed over charcoal, but it's still heavenly. Trout has very little calorie content, and the simmering time, no matter how low the flame, consumes quite a bit of fuel, but this type of meal is one of the luxuries worth doing on a multi-day backpacking trip.
Turns out the Primus exceeded all our hopes. At the time of this update, the stove went through seven long hiking seasons, 25-30 nights each, boiling at least two quarts of water every day. Of course, we take good care of it, making sure it's always clean and we never leave it exposed to precipitation or blowing dust.
No part ever failed and we never had problems finding shelter for it in wind and getting it going in sub-freezing temperatures.
It's light (still one of the lightest), easily packable and as it seems, very durable. I don't have any experience with their customer support as I never had to call them.
Another note: if you want to read about pretty much every aspect of camping stoves, visit zenstoves.net. They have very detailed info about every conceivable type of stove, cooking system and fuel you can – and can't – imagine.
Another update: during its 8th season, the stove suffered a serious accident. I lost my balance and fell on it, with its support arm open. It scratched my palm, leaving a wound that looked scary first, then healed really fast. The stove suffered more lasting damage: one of the arms was bent badly. Carefully, I bent it back and we kept using it for a little while, but it was never perfectly stable again. We started researching new stoves, see what changed in the last few years. Finally, we settled on and bought a Soto Amicus. It’s a bit heavier than the Primus, but it’s regulated and it handles wind much, much better. We used it for half a season so far, and it did great, using less fuel and truly being better in the wind. However, we haven’t used it enough yet for me to write a full review. Stand by.