Monatauk Gnat Stove Review

Companion forum thread to:

Monatauk Gnat Stove Review

Ok, it looked nice, how did it work?

it's pretty safe to say that there is precious little difference in these stoves

I have the Gnat for some months and on my website you can see a short video of it... (It's in German, but I think that's okay for video)

http://qbloggt.blogspot.com/2010/03/monatauk-gnat-das-video.html

Edited by heidelberger on 06/23/2010 02:16:05 MDT.

numbers ...

Actual usage figures for the Monatauk Gnat and its twin brother the Go System Fly can be found at

Gnat

Gosystem Fly

How does it simmer?

I normally use alcohol stoves, but I do have a 10 year old Gigapower in my closet which I use occasionally. My major complaint with the original Gigapower is the slippery pot supports. One time my tall pot slid off the Gigapower supports and scalded my hand with boiling water. Not fun in the backcountry.

Recently I have been considering getting another canister stove, but ingrained in my memory is the sight of my beet red scalded hand, so pot supports are a major concern of mine. The Monatauk Gnat appears to have good pot supports, but judging from pictures on the company websites, I prefer the pot supports of the Gigapower LiteMax, at least for a tall tippy pot.

According to the Monatauk website, the Gnat costs $60.00 American

Price?

The unit Ryan got was from Monatauk, but my information is that it was actually designed and made by Fire Maple in China (where else). It is available from several sources around the world under various numbers or names, but sometimes with '116T' in the part number.

Specifications:
Dimensions: 55 x 75 x 32 mm
Weight: 48 g
Rated Power: 12,000 BTU / 3,500 W
The measured CO emission is around 10 to 20 ppm, which is pretty good.

I can verify that it does punch out a lot of power, consistent with the claimed figure, and considerably more than any white gas stove (so there!). I can also confirm that it does simmer very nicely, and that the valve action is smooth.

Pricing varies depending on the supplier. Someone else mentioned $60 from Monatauk, but I have not verified that myself. It is available for ~$35 +P/P from Shanghai, at
http://www.de-maritime.com/titanium-camping-stove

Disclosure: I received a review sample from DE-Maritime as well, but Ryan beat me to the punch in submitting the Spotlite.

Cheers

I like this review - it is concise.

The pot stand legs of the Gnat are similar to my Brunton FLEX stove in design. I fixed the wobbliness of the legs by drilling out the rivits and replacing them with tiny nuts, lock washers and bolts. The lock washers held the pot supports snug enough to prevent wobble but not to tight to make folding difficult.

As is often the case many backpacking products can be improved upon with a little thought.

Edited by Danepacker on 06/23/2010 23:21:36 MDT.

"""I like this review - it is concise"""

Agree with Ron

May be too much concise..........:-/

+1 on the concise review.

Could just use a set of those plastic jetboil legs with it... they clip really nicely onto the bottom of a small canister and are pretty solid. Just a thought!

Roger, thanks for the verification and extra info. How is it in terms of CO emissions?

Hi EJ

> How is it in terms of CO emissions?
Fourth line in the specs I posted! 10 - 20 ppm. That's fairly low.

Cheers

The review was concise because there just isn't a lot to say about a product that seems to work as well as anything else.

The real appeal of this stove to me was its aesthetics, which are superb. In terms of "lightweight philosophy in design" this stove hits the nail on the head.

"It works well enough" - and I do mean that.

The differences in field performance between all these little canister stoves is so infinitesimally small that it's almost ludicrous trying to figure out how they compare to each other based on performance - boil times, fuel efficiency, etc.

It keeps both big and little pots stable, it hasn't failed yet, and it makes hot water. "I guess it works, eh?" I know, I'm being a little tongue in cheek here, but seriously, there just isn't a lot of room left in this product market and I just wanted to point out something aesthetically unique in a pretty crowded field.

What's remarkable to me is this:

Bushbuddy Ultra - 5 oz
Gnat Stove - 1.7 oz
Cat Food Can Stove - 0.5 oz
Esbit Ti Stove - 0.3 oz

i.e., today, I can cook on wood, gas, alcohol, and solid fuel on the same trip (if I wanted to, but I wouldn't, except when on a teaching trip) for 7.5 oz! How cool is that?

Good review. I would always wish for complete specs to include stove measurements folded and in use, stove weight, case weight, case size and maybe even burner diameter. We are still missing the case weight. A few more specs are

stove weight: 1.6 oz (48 grams)
stove size (folded): 2.25" x 2.25" x 2.5"
stove size (in use): ?
case weight: 1.4 oz (hard side)
case size: 3" x 3" x 3.25"

Edited by jshann on 07/30/2010 08:12:13 MDT.

John,

Toss the case. Thus, case weight = 0.

Seriously, though, I can't see any compelling reason to bring a "stove case" on a trek.

I know it's there to protect the stove, but wrapping in a viscose towel does it for a lot less weight and rattling.

Ryan

The stove case is dual purpose.

It protects the stove from breakage, and it protects the other gear in your pack from the sharp points on the stove.

If I wrapped a viscose towel around my stove, it would be full of holes in a week's time. But then, I suppose that is why I carry duct tape.

--B.G.--

How does the Gnat stove performance compare to the Soto OD-1R Micro Regulator Stove in terms of maintaining consistent output in cold weather? Although many stoves may seem alike, the Soto appears to have an edge in performance as temp drops and as fuel runs out, i.e., the Soto output is the same across the spectrum.

"the expedition-conscious ultralighter can turn down the fuel power and eke out thirty-six to forty boils (at 12 oz/boil) without much difficulty" What sort of altitude are we talking about here? I imagine there's quite a large variation in how long a canister lasts between say 10000 feet and sea level.

> I imagine there's quite a large variation in how long a canister lasts
> between say 10000 feet and sea level.
No, altitude will have very little direct effect on the life of a canister. The canister supplies energy, and how much energy is in the canister is unrelated to altitude.

However, because the ambient temperature drops as you go up in altitude, you will find yourself using a little more fuel to get water up to 80 C. On the other hand, water boils at a lower temperature at higher altitudes, so you will need a little less fuel to go from 80 C to boiling. Ho hum ... :-)

Anyhow, most of that is irrelevant. What really influences practical fuel consumption is wind, use-of-windscreen, heating rate, lid-on-pot, and other things like that. They are far more significant, to the point of being totally dominant.

Cheers

The Snow Peak Giga weighs 3 oz., but that includes the "ignitor". You have to weigh in whatever it is you use to light the Gnat stove.

Edited by rambler on 07/06/2010 22:04:39 MDT.

not really, ignitors fail so frecuently that you MUST to carry one lighter anyway

Agree with Carlos. You still have to carry a lighter/matches. We had a jetboil piezo ignition fail this past weekend in the Pecos Wilderness.

I have never purchased a piezo ignitor stove, preferring to use a mini lightmyfire striker instead, which can also be used to start a "fire" in the old fashioned way as well.

No one has said anything about the corrosion resistance of titanium.

Is the burner itself titanium? How does it look after it's been fired a few times? I've seen used non-titanium stoves of similar type for sale (ebay) and the burner is all rusted. May still work okay, but aesthetics are important too. Charred, rusty stoves are ugly. If this stove avoids that, it should score points.

On the other hand, some parts are aluminum, how well do these parts hold up?

When first lit, my Gnat burns a blue flame, but after 30 seconds it turns orange.



Anyone else experience this?

Does it matter?

As a general rule, if the flame color is different from what you expect, then there is a problem of some sort. If the flame is supposed to be blue-hot and it is only orange-hot, then that suggests a "breathing" problem, like if the cold air intake is clogged with foreign material. It is possible that the fuel is contaminated with something, but with a butane canister stove, that would be very unlikely. It is possible that there is some foreign contamination in the top of the burner, like spilled food. The top of the burner is normally titanium or stainless, so it does not corrode even after serious heat. Those metals might change color slightly, but that is normal.

--B.G.--

Bob

The same canister wth a different stove is fine, so not fuel contamination.

I took the burner apart to look inside. The burner is titanium with a fine mesh (presumably stainless steel) inside. No dirt. The jet looked ok although I didn't remove it as I may want to return the stove.

The flame starts off blue as I would expect, but turns orange once the stove has heated up, about 30 sec

On most of these stoves, the cold air intake is a pair of open holes on the sides and between the fuel port screw and the burner. Did you poke around in there? One tiny bit of leaf could really clog things this way.

--B.G.--

Bob

This stove is brand new, fresh out the box.
There is no accumulated dirt and no obvious bits of swarf anywhere I can see.

Hi Stuart

Same problem as we discussed before.
But I don't think mine does that ... what happens when you turn the power up?

cheers

Hi Roger

Similar problem as previously discussed - *some* part of the burner must be getting too hot.

The only part glowing visibly are the pot supports. However, the 'windscreen' on a Pocket Rocket also glows but doesn't result in an orange flame, so I don't think that is the problem.

So, it must be something inside the burner? I had a quick look and saw nothing obviously wrong, but I'll take another look.

The power is already quite high in the photo, turning it right up doesn't make much difference.

I didn't see any video reviews of this stove showing this problem, it must be just me :-(

Stuart,

I found this in a gear review of the Gnat on Backpacker.com.

>>Two tips: 1) Don’t forget to pack your own windscreen because the burner is very susceptible to breezes, and 2) Screw the canister on tight. (I noticed a big difference in output between a lightly screwed on and a cranked on canister.)<<

How close is the aluminum control valve housing to the "rim" of your fuel cannister? Does it contact the rim of the cannister as you are attatching the stove to the cannister?

The change in the color of the flame suggests to me a change in the air fuel ratio. Is it possible your are going to a "lean" mixture of air and fuel due to the fuel cannister not being firmly attached and fully open at the self sealing cannister valve?

Compare the parts of the two stoves that connect to the cannister. Is the part of the Gnat that opens the self sealing valve on the cannister clean and able to fully open the self sealing cannister valve?

Looking at pictures of the Pocket Rocket stove I notice a seal of some sort between the stove assembly and the fuel cannister. Is it possible that the Gnat is "drafting" excess air into the fuel mixture at the cannister / stove connection?

I am very interested in this thread as I am contemplating the purchase of a Gnat/Fire Maple stove myself.

Party On,

Newton

John

"How close is the aluminum control valve housing to the "rim" of your fuel cannister?"

Gas starts to come out of the canister when the clearance from the control valve housing (the orange bit) to the canister rim is 0.3 - 0.4mm for two different canisters.
The stove then screws on for a further 0.3mm without excessive force.

I think the seal between canister and stove is good. In any case, a bad seal here would result in gas leaking out, not air leaking in.

I took the stove apart again and had a good look, but still didn't notice anything obviously wrong.

Ho hum

Stuart,

Are all other parts of the stove above the orange "valve bit" assembled tightly before and after the testing? Excess air in the mixture?

Can there be anything blocking the flow of gas to the jet/burner? Pressure of the fuel being delivered to the burner reduced? A part of the cannister seal?

Is there anything that can be causing a catalytic reaction of the flame where you are testing the stove? The color change?

Party On,

Newton

Hi Stuart

OK, I got mine out and fired it up. It started out with a blue flame as should be, but as the middle of the Ti pot supports bits got red hot it gradually developed the orange colour you showed.

Diagnosis:

The red-hot metal at the burner face is causing a change in the chemistry of the flame, with atomic carbon being generated too early for combustion. The carbon atoms are glowing in the flame as the hydrogen is being burnt first. I think most of the carbon does get burnt up higher up. This does not (normally) happen with other stoves when there are no red-hot bits in the flame.

So ... I took the pot supports off and tried the stove again. It lasted longer before getting an orange flame, but the top of the burner face did slowly get red-hot, and then the orange glow returned.

I note that this burner has a double layer of mesh under the Ti burner face. That should stop it from getting any flash-back or internal ignition, and the inner layer is unlikely to get as hot. Field testing has not shown any problems of flash-back either.

You can 'improve' the performance (ie reduce the orange glow) by *restricting* the inwards air flow. This makes the flames just a little longer, so they don't heat the burner face as much. The heat is higher up or further away. Blocking one air inlet hole may be enough.

However, as I said, field testing has not shown any problem with this burner, so you could just ignore the problem ***in my humble opinion***.

Cheers
Roger

Does it make a difference when there is a pot of water on it heating up? Perhaps the stove will not have a chance to develop much of the orange flame if a pot is on top and the stove is switched off after boiling. That is, perhaps field use will prove to be less enigmatic.

Hi Roger

Thanks for taking the time to reproduce this and for your diagnosis.

"I think most of the carbon does get burnt up higher up."

Normally, formation of carbon/soot is associated with carbon monoxide which is not further oxidised, usually due to insufficient oxygen altering the reaction pathways, or flame quenching.

In the Gnat flame carbon is being formed, and the flame will be partially quenched by the cold surface of a pot.

That might be expected to lead to high CO levels. Your published measurements indicate that this is not the case, but despite this I can't help being just a little worried, as I often cook in the tent vestibule.

cheers

Edited by Scunnered on 08/22/2010 02:43:47 MDT.

If there is an increase in carbon in the flame, will it create soot on the bottom of pots?

> If there is an increase in carbon in the flame, will it create soot on the bottom of pots?

I don't think the amount of free carbon is all that high. the orange glow is very faint compared to, say, a candle flame. And I have not seen any soot accumulate on the underside of my pot.

Cheers

Being a gear junkie, I was forced to purchase one.

I started a sea level test with everything at a temperature of 60 F. One 16-ounce aluminum kettle with 16 ounces of water in it. I had a full rolling boil in a hair over 3 minutes.

In the protective case, it is smaller than a Pocket Rocket. Out of the protective case, it is much smaller than a Pocket Rocket. Not bad.

--B.G.--

I recently replace my Snowpeak GS-100 with this Gnat. FWIW, it also develops the orange flame. Just wondering if anyone has an idea for a canister heat shield like Snowpeak makes for the GS/GST-100?

On my last trip, I noticed that the flame one one side of the burner was bigger than on the other side. When I got home I took it apart. On the underside of the jet there is a little 'plug' made from lots of tiny balls sintered together to act as a filter, to stop the jet getting blocked by any bits I assume. Anyway this filter plug was loose - one tap and it fell out!

Reassembled without the plug and the stove was not happy at all - the flame was lifting off the burner and had big yellow tips. Clearly the filter must restrict the gas flow and the jet must be sized to account for this.
I disassembled, replaced the filter plug, pushing it in firmly with the shank of a 4mm drill bit, and reassembled the stove. Now it's running fine - a nice blue flame evenly distributed around the burner.

So if you have any problems with the flame on a Gnat, this filter plug is something to check!

Did it look like this ?

This one is the one in that BuLin 153g stove...
Franco

Hi Stuart,

Thanks for that advice, my Gnat stove (sold as Kathmandu Backpacker stove Titanium in Australia) has problems too, when the flame is turned up the flame goes very strange, it is interesting that the filter is required to slow the gas flow down. I will have to dismantle my Gnat to check the sintered bronze filter has not come out.

I have been trying to remove the sintered bronze filter out of my Bulin BL100-B5 stove jet, it is not budging.

Hi Franco,

Thanks for the high quality photo of jet filter, I know your photographic skills are better than mine.

Tony

Edited by tbeasley on 09/09/2011 04:41:24 MDT.

Hi Franco

Similar, but not the same. It consists of lots of small brass balls packed together into a truncated cone shape which then press fits right inside the jet screw, whereas yours looks like it sits at the bottom surface of the screw.

Edited by Scunnered on 09/10/2011 07:18:30 MDT.