Soto StormBreaker

Discussion in 'Japan' started by Reflector, Sep 16, 2020.

  1. Reflector

    Offline
    Joined:
    Dec 26, 2013
    Messages:
    47
    Location:
    Denatured Alcohol Pointless Ban Land (California)
    I'm surprised the Soto Stormbreaker never got a post nor did Hikin' Jim finish his review, especially as the Stormbreaker seems to be temporarily out of the US market (according to the Soto US website blog). I was fortunate enough to get a second hand one from someone who was parting from theirs and it is now my second air-fuel mix start stove next to a Snow Peak Gigapower WG.

    I have it modified with a lot of heatshrink because the fuel line is extremely flexible. So flexible that I feel that it needed some protection around the ends, especially on the end that goes to the pump. On that end there are two layers of heatshrink to give the line variable compliance. Where it is closer to the crimp, there is more stiffness and then the single layer allows for a "soft" transition rather than a hard pinch. Equally, the silicone boot on the stove end is a good idea but it acts like a hard pinch point potentially so I added heat shrink. There is a little bit of heat shrink on the legs/pot stands to act as rubber feet and to serve as insulation for handling the stove as well.
    Stormbreaker Folded.jpg Stormbreaker Unfolded Top View.jpg
    Stormbreaker Box Front.jpg Stormbreaker Box Back.jpg Stormbreaker Box Side 1.jpg Stormbreaker Box Side 2.jpg
    Stormbreaker Burner Head.jpg Stormbreaker Intake Holes.jpg
    Stormbreaker with Pump.jpg Stormbreaker with Isobutane Adapter Folded.jpg Stormbreaker with Isobutane Adapter Unfolded.jpg
     
  2. Reflector

    Offline
    Joined:
    Dec 26, 2013
    Messages:
    47
    Location:
    Denatured Alcohol Pointless Ban Land (California)
    Also a reference to trying to run it on charcoal starter/lighter fluid in some of my experiments with it so far and a followup:
    I ended up mixing around 1/3 to 1/4 (by eye, pouring it back into the bottle from another) of the charcoal starter fluid (CSF) / charcoal lighter fluid into white gas. Rather than start it up from a cold generator by using the air mixed start, I took a torch lighter and briefly heated the generator across the part over the burner for around 8 seconds. I kept the lighter going and turned the pump valve to start and the Stormbreaker started up with a deep blue flame that pulsated with a little bit of orange but it otherwise was a deep blue.

    It seems to work and I assume this is closer to something like Amish mix where white gas is mixed with kerosene (and vice versa for kerosene stoves). The Stormbreaker continued to heat up and after around 20 seconds I put a frying pan onto it only to be surprised for a brief moment as the cold pan caused the same nasty odor but it only lasted for a few seconds before the pan heated up. I did not notice any soot afterwards much like when I was running straight CSF through the Stormbreaker.

    Adding some pressure to the bottle seemed to allow for outrageous amounts of heat output. I have only ran the Stormbreaker twice on white gas but adding the extra pressure to the mix of CSF+WG in the bottle, I found that the flames would flatten out as a disk that was larger and flatter against the pan bottom than it would on straight butane. They went over the edge of the pan I had which is around 8" and started to go up the sloped sides by around an inch much like the Windmaster does when it is at full throttle.

    When turning the stove off from normal operation, the nasty stinky smell of the CSF is present and I found that running the stove back on start briefly would help "burn off" the odor before turning it over to air to let the pressure out of the bottle. Doing the normal run -> start -> air procedure seems to prevent the smell completely.

    If no inexpensive/reasonable gallon quantities of white gas are available, CSF seems to be "viable" way to cut fuel in some stoves including the Stormbreaker. Doing the math, I was paying a dollar for 9,471 BTU out of the quart bottle CSF. Comparably, a quart of white gas for $5.27 is 6,129 BTU per dollar. If I had bought the bigger 2 quart/64oz bottle of CSF it would have been around 11,937 BTU per dollar at $4.57. These numbers are before sales taxes.

    I assume that kerosene burning stoves or stoves with "hot" generator loops would do better as it seems CSF behaves like a very high boiling point naphtha or "heavy naphtha" - at least the stuff I get in California anyways.
     
  3. Reflector

    Offline
    Joined:
    Dec 26, 2013
    Messages:
    47
    Location:
    Denatured Alcohol Pointless Ban Land (California)
    A bit of some longer term use remarks below.


    Wind resistance and burner characteristics:

    The Stormbreaker seems to behave a little like a Windmaster but with the Triflex legs which have a 1/8" higher gap to the pot. The flame flattens out at high power settings and forms a nice big disk on the bottom. It is not as "even" as the Windmaster with 4Flex legs which seems to act like a horizontal side burner with a little bit of a hotter central spot. The flame pattern has a little bit of a hotter spot in the center and a wide disk of heat.

    If using the Stormbreaker at high power settings to fry things: Aluminum pans with teflon are advised along with thick based/sandwiched pans. I have found that the Stormbreaker works wonderfully with a very thick Anolon pan ("Nouvelle Copper" line which is very heavy from the base and tippy due to the handle offsetting the center of mass) along with my GSI Pinnacle Radiance pan. In contrast with a stainless steel clad (aluminum core) “USA Pan” it will burn food in the center spot with frozen meat suspended in water if it is not watched and constantly prodded after 15-20 seconds. In contrast the thicker pans or those with good heat conduction and teflon when loaded full work wonderfully.

    As an "estimated power equivalence" thing, I would say that the Stormbreaker on white gas when fully pressurized to the point of it being hard to pump is comparable to when I use a heat exchanger frying pan ("Turbo Pot" brand for the curious, it doesn't work too well for camping/backpacking stoves as the fins are deep and in the center but it works well on home burners) on a 17,000btu triple ring wok burner with what feels like a decent amount of heat spilling over the ends of the fins of the pan. Of course, this is with the Stormbreaker in use with a normal non heat exchanger pan.

    I would be very cautious on running the Stormbreaker at full power for extended periods (as in “seconds” when the pan is already hot) with any nonstick pan that isn’t made out of a fairly thick aluminum base like any of the MSR ones as the heat might not be able to be spread evenly and quickly enough to avoid damage to the coating.

    It matches very well against a Jetboil 5L pot for boiling lots of water. At max power the flames barely just touch the fins and I do not smell uncombusted gas at max pressure. Throttling a little back I suspect would make the Stormbreaker fairly safe to use with a visual inspection to see if the flames are touching the fins and with the pot well centered.



    Torch assisted quick starting/quick start capability:

    I think the Stormbreaker works best when it is used with a torch to reduce liquid consumption. With a little gentle heating of the generator (10-15s with something like a small jet lighter of any sort) the Stormbreaker can be used immediately with a pan or pot set onto it without a bit of fuel being wasted for warming it up due to the air premix. I also believe the stove heats up quicker as well (in my experience) from seeing signs due to flame liftoff.

    I can tell that the Stormbreaker is "ready" to be turned from the start position to the normal run mode when the flame begins to lift off the burner head. When the stove is more than sufficiently hot for operation, the flame will begin to briefly lift off the burner head for a moments at a time and potentially go out. That's about the right time to turn the valve from start to the normal run positions. The stove is generally sufficiently hot if running pure white gas to turn it over before this, so timing how long it takes to go from a cold start to this and subtracting some time off of it is sufficient to figure out how long it has to run for. I am still trying to burn off all the charcoal lighter fluid that I have mixed with white gas and so I use the flame lift off as a reference because the stove is nice and hot to vaporize the charcoal lighter fluid.


    Bottle sizes:

    The bottle it shipped with or I believe it shipped with is a 480ml/16floz bottle when the pump is put into it. The actual capacity of the bottle is around 700ml/24oz, which means even if mostly filled the thing has tons and tons of air space. In contrast, the smaller 280mlml/9.5oz bottle that is not available in North America has 400ml/14oz of actual capacity. That means with the larger bottle, most of the pumping effort will be spent filling almost twice the air space in the bottle.

    Normally I prefer to fill my liquid fuel stove bottles almost all the way up full but the Stormbreaker makes use of a lot of the air in the bottle for the rapid start feature. Normally if a stove is primed (with alcohol on my part) it just needs "enough pressure" in the bottle to push the liquid through. With the Stormbreaker, the stove is actually fairly dependent on pressure in the bottle to operate at full power but simultaneously it needs a bit of air during startup.

    The air usage can be reduced by using a torch to briefly heat the generator to avoid having to prime it and it is definitely faster - I have found that using a torch allows me to directly set a frying pan or pot on the Stormbreaker within seconds of igniting it after quickly heating the generator loop with a torch lighter. Around 20-30 seconds in, I can turn the valve from start to just a normal run and the flame transitions.

    I have found that this means with the larger bottle more time is spent primarily pumping the bottle up full of air because more pumps will be needed to bring the stove to "full" operating pressure. Once the stove goes from "start" to normal, because a large volume of air has gone to the quick start feature the pressure in the bottle is fairly low. If there's very little fuel in the bottle then it takes a whole lot of pumps to bring the stove up to "full" power. By the time I'm done I find that I end up already cooking whatever I am cooking with or otherwise boiling anything but a huge amount of water (3-5l).

    Using the smaller bottle alleviates this in my experience, something I've stuck with when it comes to all my other liquid stoves. With the bottle mostly full and with a torch preheat, by the time the stove is done in "startup" mode, I can just switch it to normal mode and give it another 10-30 pumps to the point it is hard to pump and the pressure indicator pops out with the red line fully and have a full power burner. Less pumping involved overall and less depressurization too when I'm done.

    Not sure why Soto doesn't offer the smaller bottle for sale, aside from the Stormbreaker not being sold in the US currently. I have always personally found it better to pick the smallest bottle for the stove pump to go into and to have another bottle/container to store the fuel in like the Trangia ones or the plastic/metal quart containers of fuel.


    The pump and preliminary reliability:

    I read about the pump potentially leaking but so far with my very gentle use of a second hand pump it seems to have held up fine. I have left it pressurized before and it doesn't seem to have leaked but the bottle was stored upright. The pump reminds me of the Primus ErgoPump where the piston, cylinder and a few other pieces of hardware are plastic but the threaded part is plastic.

    The (very complex) valve mechanism is probably the niftiest feature. Push down to cut the flow is nice and having a 90-ish degree swing arc for flame adjustment makes it behave more like an actual kitchen range. The only thing is that with a lot of pressure in the bottle it is kind of finicky to get the super low simmer settings as it involves slowly dialing the valve setting while watching for the flame to bump it back up before it goes out in a shaded area or at night. Beyond very slow simmers, general adjustment is quick enough that it seems to slowly begin to throttle back within 1-2 seconds with a little bit of latency. Throttling up is super-fast and responsive by contrast.

    The fuel filter which is a sintered piece of bronze can be twisted off the line. The line doesn't have to be cut like Soto's diagrams advise and I wouldn't cut it because the fuel and air lines seem to be additionally caulked to seal it in or otherwise glued in on the outflow side. While a little cut probably means very little, I would avoid any destructive acts to the line, especially when the filter just inserts back in. Maybe it could be "backwashed" or otherwise replaced for long term purposes.

    The little debris guard is a nice feature but it isn't included on the butane adapter for some reason. The small hole on the quick connect fitting along with the debris blocking mesh just before the jet makes me believe that it is a little vulnerable. I would put something like a piece of heatshrink with the end sealed or a plastic cap over the butane adapter because of that.


    Output difference between pure butane vs white gas and additional remarks:

    Room temperature pure butane (not isobutane mixes) has reduced output even in liquid feed mode in contrast to white gas. A little bit of "warming" of pure butane cans (as in the long cassette stove type) to bring them closer to body temperature will cause the output to rise but the Stormbreaker seems to be optimized for white gas in my opinion. With a fully pressurized bottle (read: hard to put any more pumps into if the bottle isn't pressed against something on the bottom end) the Stormbreaker just throws heat out with a nice warm glow.

    Pure butane does have a lower operating pressure: At 125F it only hits 61psi. In contrast, a 70/30 butane/propane mix which is comparable to some isobutane/propane mix ratios has around 60psi of pressure at 40F. At 70F, pure butane only has 17psi of pressure, the 70/30 butane mix has 20psi at 40F. I can only assume that the Stormbreaker operates excellently off proper isobutane mixes compared to butane and otherwise would be very happy with propane assuming nothing bad happens with the seals.

    Pure butane seems to vaporize in the adapter readily when it is 70F, the butane doesn't actually hit the loop as a liquid. A little bit of chill is felt on the adapter.

    The long cassette stove canisters actually can be used in a nifty way with the right adapters where the adapter doesn't need to have both legs deployed. The double o-ring on the butane adapter seems to fully seal against the cassette canister adapters early on and has over an entire turn more in which it can be tightened. I have found this allows me to start the stove with the butane canister lying on the side with the notch facing up for gas feed before further tightening the adapter to rotate the notch 180 degrees so it feeds in liquid mode.
     
  4. presscall

    presscall United Kingdom SotM Winner SotY Winner Subscriber

    Offline
    Joined:
    Aug 25, 2009
    Messages:
    9,858
    @Reflector Yes, a review was overdue, but you've put that right in good style with in-depth, well-observed and well-photographed coverage.

    It's a stove I've been looking out for to buy used, being unwilling to pay the hefty new price, but if one doesn't come my way it's of no consequence. It'd be a collection acquisition and not a desired 'user' stove. The pump's as complex as ever, full of O-rings, and the weak link in terms of long-term reliability in my opinion.
     
  5. ROBBO55

    ROBBO55 Subscriber

    Offline
    Joined:
    Oct 27, 2014
    Messages:
    1,179
    Location:
    Somersby, New South Wales, Australia
    Thanks @Reflector for a well writtenand detailed assessment. :thumbup:
     
  6. Reflector

    Offline
    Joined:
    Dec 26, 2013
    Messages:
    47
    Location:
    Denatured Alcohol Pointless Ban Land (California)
    I hope to write more of a proper review or at least get down more of my thoughts in detail but for my purposes of evaluating a rare stove ("not sold in US currently") I was surprised there was so little information on it especially on the in depth side. When I get a chance I'll see if I can do flame and action shots at night to add to the gallery as well.

    I bought mine second hand and I don't have a regret about it given how gently the previous owner treated it. I think it'd be a wonderful stove at what was the US retail price ($180 with the bottle (sometimes?) from what I can tell) along with those biannual/annual sales that most of the US retailers have where they offer 20% off a full price item. Mine was close to that second hand and I like it for being a current production quick starting stove.

    I definitely would agree in that it lacks the reliability or maturity like the MSR, Optimus and Primus designs from the pump design. So far mine has been well behaved and I have yet to experience any pump problems. Soto USA seems to still support it as well in regards to parts when I wrote to them but they just simply don't list the generator as being available like the Muka (which is a "consumable" due the buildup of deposits in it, which I can’t understand why it couldn’t be cleaned).

    The other thing is the wide mouth bottles are definitely proprietary and that's another downside. I usually run my fuel through a funnel with some filter mesh first so the benefit of the easier to pour side is a little lost to me aside from how it is easy to top off from a little Trangia bottle. Soto does seem to use up the larger throat of the bottle for their pump but I can't help but feel something like a mix of the Primus ErgoPump mixed with a little bit of Snow Peak WG pump could have been made with more "protrusion" from the part of the pump that sticks out beyond the canister

    Maybe something like the MSR pump or Primus pump could receive a small diameter shrink and an air tube with the valves set further topside and designed like the Snow Peak Gigapower WG where it is a valve of its own could be a better alternative to the otherwise "featured, convenient but complex" design of the Soto. They do seem to have some nifty designs on valves like on the Amicus where it isn't a metal on metal seal for the valve but instead seats against an o-ring for the closed position.
     
  7. Reflector

    Offline
    Joined:
    Dec 26, 2013
    Messages:
    47
    Location:
    Denatured Alcohol Pointless Ban Land (California)
    Jet prefilter and cleaning the stove

    I may have to retract the statement about very well pressurized fuel canister for power, it seems I may have had a very slow acting clog that built up over time. This also marks my first "malfunction" with the Stormbreaker so far but I think the charcoal starter fluid is likely attribute of my own fault. I had noticed that not only was the butane performance underwhelming in a recent firing but significant underburn was occurring. Later in the day I had fired the Stormbreaker up on liquid fuel and it seemingly struggled to the point that barely any output was there.

    When I took the little cap and filter on the bottom off a bunch of fine black powdered specs dropped onto the aluminum plate I was working on as a surface. There were a ton of little specs captured by the filter with some pieces embedded into it. They easily bounced off with the gentle fingertip touch. Taking the little cleaning wire out and prodding into the jet, I noticed even more pieces of fine carbon falling apart. Inverting the stove I had even finer pieces fall out into the plate I was working on...

    A few prods and with the cleaning cap reassembled all the power was there and even some more with how pressurized that bottle was. The flames were more than enough to saturate the heat exchanger fins on the kettle I was using at full power. Curiously no smell of unburned fuel this time, just disk of fire that was over a half inch/centimeter "thick" off the base of the kettle that rushed towards the fins of the kettle. Maybe there was just enough heat there to ensure total combustion just as the flames hit the heat exchanger fins. A bit of a different experience than when I had set a very thick pan onto the Stormbreaker and I could smell a little bit of the stink from the charcoal starter fluid I had mixed into the fuel.

    To conclude: There was plenty of power without having to crank the valve full open after significant work to pressurize the fuel bottle until it was very difficult to pump after a cleaning.


    More remarks about charcoal starter fluid

    I have gone through close to a liter/32oz of charcoal starter fluid and at 1.5-2x of that in white gas, in a mix. I have been using a red, 32oz of "Premium" Coleman fuel. This is in addition to at least more than 16oz/450g of (non-iso) butane as well.

    Skip the charcoal starter fluid, even with a fuel filter. Maybe there's something in it that causes the carbon. Maybe not. Maybe it comes from my startup method of torching the generator a little. At least cleaning was extremely straightforward and took no more than 2-3 minutes. If anything that little prefilter screen likely saved me from a nastier clog.

    It at least works in an emergency "if you must" and want a fuel comparable to buying a gallon of white gas at $8.86 in regards to btus per dollar, especially when buying what is effectively a quart or two of it. Maybe it is less nasty than unleaded gasoline but it definitely doesn't play nicely and needs to be mixed with some white gas (I find that 50% is still "tolerable") when it comes to the Stormbreaker.


    A small caution about reassembly of the cleaning cap

    Also remember to properly "snug down" the jet cleaning access cap after feeling it tighten or small amounts of white gas vapors will leak out at very high power settings. This is more of a danger if the stove is started up initially as a tiny spray of white gas vapors will suddenly appear on the bottom of the stove. This can potentially pool up and cause a fireball so stove shutdown at this point is necessary. When in operation normal operation before the stove is throttled up the vapors are sucked back through the air intake holes in the bottom and burned with whatever remainder going up over the sides and being sucked up into the flame. At least that was my experience with my heat exchanger kettle, which likely "ducted" some of the airflow.


    Pure butane operation


    I still believe it to be a little "underpowered" as the Stormbreaker appears to be highly dependent on having sufficient pressure to operate. What I did is unadvised unless exceptional caution is taken: I started the stove up and set the flame to a super low simmer on butane and waved the canister far above the flames to warm it up until the pure butane canister reached a little cooler than body temperature before firing the stove up at full power in liquid feed mode. Output appears fairly reasonable but nothing like the insane output from operating off my misadventures of running white gas that is diluted down with the remainder of the charcoal starter fluid.

    For anyone wanting a safer method in contrast to the unadvised mention above: Warming a little bit of water up in a bowl until it is a nice lukewarm before turning the stove off and dunking the end of a long butane canister in is far saner than waving a fuel canister over an open flame. Butane has far, far lower operating pressures than isobutane mixes as a given so for anyone using safely refilled canister with expansion space then this will likely allow for the butane to have the necessary output.

    I am fairly certain propane and isobutane mixes are extremely well behaved in the Stormbreaker and will have to conduct some tests to give remarks. A can of close to body temperature butane works extremely well and looks to be close to a "medium" power setting when compared to liquid fuel.
     
  8. Reflector

    Offline
    Joined:
    Dec 26, 2013
    Messages:
    47
    Location:
    Denatured Alcohol Pointless Ban Land (California)
    Bottle fill line

    It turns out the line that Soto gives isn't the actual max fill line, using the smallest bottle I find that it can be fueled up right to the shoulder and still have some sufficient working air space. The only thing is that the bottle has to be pressurized at a higher pressure and some additional pumping is needed during the priming as the bottle quickly depressurizes due to the smaller volume of otherwise high pressure air. It does however mean less pumping overall.


    More remarks about CARB approved charcoal lighter fluid

    It seems 32oz lasts far longer than I ever would want to deal with the stuff. If it is truly too hard to find white gas and one is insistent on burning something "other than" regular unleaded then I would say charcoal lighter fluid may serve as an acceptable alternative. It is cheap (dollars per BTU it is around 140% "more expensive" for a 32oz bottle than white gas at $8.86 a gallon) and it seems to burn sufficiently well when the stove is heated up when it is mixed with a little white gas to make it vaporize easier.

    For anyone curious about the maximum ratio of charcoal lighter fluid that can be run in the Stormbreaker and still achieve acceptable function without any particular odor and with a "pretty low" simmer setting for non-hiking meals for a 2-3 people is about 1:5 to 1:3 depending on how much one wants to spend preheating the stove. With a little torch pre-heating the stove heats up quickly in around 20 seconds with a little bit of dancing between alternating the valve from start where it runs a little too rich and then back to air to burn away the excess lighter fluid. Once hot, the stove will happily run at the highest of power settings and then throttle down carefully (with a very pressurized bottle) to the point that it wants to go out. I can only assume that this applies to mixing down kerosene with white gas given the characteristics of CARB approved CLF.

    Yes, it'll throttle down to the point the flame will be blue for 3-5 seconds, briefly turn a little yellow for a half second before the heat of the flame causes the generator loop to heat up again and the flames turn blue again. I did not smell any unburnt fuel as the stove pulsated in such a manner but I achieved a very gentle simmer in which some meat over veggies in water could be maintained at a very gentle simmer where the meat stays at around 175F. At least this is my experience with a high amount of CLF.


    Generator color as a "flame indicator"

    Also the generator will visibly "change color" in aforementioned low simmer operation. It goes from the reddish-brassy color to a brief dark coating forms from the heat being insufficient before the pulse of heat turns it briefly blue towards the jet end and then back to the reddish-brassy color. The Stormbreaker's generator will turn dark as the stove is shut off from what I suspect is unburnt fuel so aside from the acoustic tone of the stove turning, examining the generator's "color" at low throttle settings is a good way to determine if the stove is lit or not in daylight.


    Part-way settings from start and air

    The valve will allow for operation with it not being set fully to air or start, it simply reduces the flow rate and makes the stove run a little richer towards the start side if it is set a little low. I have found that the Stormbreaker can be operated at a "reduced power" start setting for less of a huge flame during startup, especially on white gas. If the generator is sufficiently hot from a jet lighter helping out, the valve can be set between off and start and warmed up with less pressure in the bottle being lost from the start position.

    Watch the flame color and the Stormbreaker after heating the generator with a lighter and it will practically "start" like a canister stove. It can be immediately followed up by placing a pot or pan over it in the start position to practically eliminate fuel wastage from starting it up all without sooting the pot or pan. The flame won't overrun the bottom of the pot and come up the sides, either. A little bit of pumping and after a minute the valve can be turned over to the normal run position.


    Less smelly shutdown (with CLF) as a feature

    The Stormbreaker will generate a bit of a stench if shut down in a specific manner when running with charcoal lighter fluid, which is more of a CLF issue rather than the stove itself as it runs and shuts down fine on white gas. From my experimentation I've determined that a little bit of fuel vapor remains and as it runs through the still hot generator it stinks because of CLF's characteristics. Shutting it down by switching to start then quickly over to air alleviates this but I have found that it can be shut down with almost no odor if done in an alternative manner from what I've previously mentioned:

    1. Turn the valve to the low simmer setting
    2. Turn the valve quickly to start until it clicks and let the stove purge most of the fuel from the line
    3. Turn the valve quickly to air until it clicks and let the flame lift off
    4. Turn the valve to stop, wait for a second
    ---
    5. Hold a flame over the burner head from a lighter
    6. Turn the valve from stop towards air but not to a full "click" then wait for a flame
    7. Turn the valve to off after the flame goes out, wait a few seconds and repeat from step 5

    I find that doing this clears the stove of CLF vapor after 2-4 cycles from step 5.

    Afterwards opening the valve to air again and letting the bottle depressurize produces very little odor beyond the smell of the fuel in the bottle itself. I would say this makes the Stormbreaker one of the nicer stoves to purge because I can do this in under a half minute and the stove is "stink free" immediately. Doing this procedure would definitely render the Stormbreaker free of white gas fumes on shutdown.