Trangia/gas stove wind tests.

These wind tests were done on my Trangia 27-1 using a Kovea Ti Supalite stove that has been modified by adding a pre-heat tube and stand, this allows the stove to be used in a remote canister configuration with the Trangia windscreen and base, the holes in the base were positioned away from the wind. The pot used was the 1 liter 27-1 Trangia pot.

Modified Kovea stove with Trangia base

The tests were done with the canister in an upright position, to get consistency I put an adjustable valve on the canister and ran the stove until the flame was at a fairly high stable level I then only used the valve on the canister to turn the stove on and off.

I placed stove on the test bench, I then placed the thermistor in the pot at 1 cm from bottom, started data logging program and at 10 second I turned the gas on and lit the stove, when water temperature reached 95º I turned the stove off, removed pot and re-weighed canister, noting the new weight. From logged data start temp was noted and fuel used, the fuel used was then normalized to grams of fuel used per 80º (g/80C)

Fan blowing wind on un protected stove

Results

Test 1, no wind, windscreen

Fuel used in grams per 80ºC = 7.5g

Test 2, wind with windscreen, stove was lit, then fan turned on.

Fuel used in grams per 80ºC = 7.3g

Test 3, wind, no windscreen, During this test it was obvious that it this system is greatly effected by wind and to raise the water to 95ºC was going to take some considerable time and fuel, I stopped the tests at the same time as the no wind test and as the heating rate is usually linear I extrapolate the results.

Fuel used in grams per 80ºC = 53.0g

Test 4, the  holes in base are placed into wind.

Fuel used in grams per 80ºC = 8.2g

Discussion of results.

As can be seen from the fuel used in the wind/no windscreen test the Kovea stove efficiency was affected quite a lot by wind but the use of the Trangia windscreen does improve the efficiency to the point where if used correctly, wind may have a very small affect on efficiency, the difference between the results of the no wind and wind/windscreen tests is very small the difference could be considered in normal testing error.

Trangia windshield under wind tests

Conclusion.

The Trangia stove system with its inbuilt windscreen is very good in windy conditions but it is preferable to place the holes away from the direction of the wind.

Windscreen tests JetBoil GCS

On the Trailspace forum I was asked a question “Had your tests been performed with a GCS pot, I think you would have seen very different results.  The GCS’s heat exchanger is fully exposed and therefore far more vulnerable to wind.”

So on the weekend I ran some wind tests on the Jet Boil Group Cooking System (GCS).

JetBoil GCS remote canister setup

Testing method

These test were done slightly different than the PCS tests as I ran the remote canister in upright configuration, I decided to do this to try and get better consistency in the tests, to do this I put a adjustable valve on the canister and ran the JetBoil stove until the flame at a high level and was stable I then only used the valve on the canister to turn the stove on and off. My STD 0.5 liters of water were used. The wind speed measured was around 12-15 kph.

GCS stove with old MSR windscreen

Results

Test 1, GCS pot and remote canister JetBoil stove, no wind and no windscreen/

Fuel used in grams per 80ºC = 5.0g

Test 2, wind with windscreen, stove was lit then windscreen placed around stove, then fan turned on.

Fuel used in grams per 80ºC = 5.5g

Test 3, wind, no windscreen, During this test it was obvious that it this system is greatly effected by wind and to raise the water to 95ºC was going to take some considerable time and fuel, I stopped the tests at the same time as the no wind test and as the heating rate is usually linear I extrapolate the results.

Fuel used in grams per 80ºC = 25.4g

JB GCS wind tests heating rate

Heating rate graph, pink line no wind/ no windscreen, blue line, wind/windscreen, yellow line wind/no windscreen

Discussion of results.

As can be seen from the fuel used in the wind/no windscreen test the GCS stove efficiency is affected quite a lot by wind but the use of a windscreen does improve the efficiency and possibly if the windscreen is setup properly wind may have no effect, the difference between the results of the no wind and wind/windscreen tests is very small this difference could be considered in normal testing error.

Conclusion.

Unlike the PCS stove the GCS stove system efficiency is greatly affected by wind but the use of a good fitting windscreen can greatly improve efficiency to the point that the wind may have little or no effect.

Some windshield tests

Following on from the hanging stoves I fired up the test bench on the weekend and ran some wind tests on the JetBoil stove that I have modified for the hanging stove.

Testing setup

 

Test procedure.

 

Part of the design of my JB hanging stove is that it does not have to be hung, it can be used as a normal remote canister stove, for these test I used the stove as a remote canister stove.

JB hanging stove used as remote canister stove

 

The stove was placed on my test bench with a small pedestal fan placed a meter away,  I placed my old Vane Anemometer on the bench and tested wind speed which was measured at around 12kph (note, the wind speed feels faster that 12kph but I could be wrong) I then attached the stove to the canister and took note of weight, measured 500g of water in pot, replaced lid.

Test with MSR windshield

 

I then placed stove on test bench, placed thermistor in pot at 1 cm from bottom, started data logging program and at 10 second started stove and adjusted to a high flame setting, when water temperature reached 95º stopped stove, removed pot and re-weighed canister, noting the new weight. From logged data start temp was noted and fuel used was normalized to grams of fuel used per 80º (g/80C)

Using Caldera cone windshield

 

 

The tests

 

The first test was with no windshield and no wind, this is used a base line figure.

 

Results, fuel per 80ºC = 6.1 g

 

The second test was with the fan on but no windshields.

 

Results, fuel per 80ºC = 8.2 g

 

The third test was with fan on and using an old MSR wind screen which was placed completely around and secured together with a clip.

 

Results, fuel per 80ºC = 7.4 g

 

The fourth test was using a Trail designs Caldera Cone windscreen, this windscreen is designed for a BPL Ti 550 pot and was too small to fit over the JB pot with the cozy on it, so I placed the windscreen as best as I could around the pot with the gap opposite the fan, the fuel line came out this gap.

 

Results, fuel per 80ºC = 6.9 g

 

Below is the heating rate graph, the fastest boil (pink line) is the test with no wind the slowest is the test with wind but no windshield.

Wind tests

 

Discussion of results.

 

First I wish to point out that these tests are not what I would call scientific, I only did one run per test and with canister gas stoves they are very hard to adjust to repeat runs, but there is a trend that fits in with what I was expecting.

 

The result clearly show that there is a reduction of efficiency with the introduction of wind, and that a windshield does make a difference, I am surprised how little loss of efficiency the JB system has with no windshield., from past tests with a normal upright stove with no windscreen there was a much high loss, I am also surprised with this system what little difference a windshield made to the efficiency and these test the CC windshield was only marginally better that the MSR windshield.

Hanging stove project

I am not a climber and probably will never be, I enjoy fiddling with stove design.

Concept prototype

I got interested in hanging stoves a few weeks ago after reading a comment about hanging stoves on an Australian Bushwalking forum, the comment reminded me of liquid feed stove system I started working on about five years ago, as can be seen from the photo I put a Pocket Rocket stove on the base of an upside down canister, part of the idea in doing this is in very cold conditions there is an option to put some of the reflected heat back into the canister, for some reason I shelved this idea until now. While I do not climb I can see some advantages of  hanging stoves in some cases in backcountry snow camping.

A hanging stove idea prototype

I started my recent hanging stove project by making a simple hanging stove bracket to hold the canister upside down, I then made some legs and a pre-heat tube modification for a Gnat Ti stove (called Kathmandu Backpacker Stove Titanium here in OZ), the legs have been made to clip on the base of the canister. This worked well except the Gnat stove has something wrong with it and I have difficulties with simmering in both the upright canister configuration and liquid feed configuration., I have since replaced the Gnat with my favorite a Kovea Supalte Ti stove and all is working well.

Hanging a Chinese remote canister stove

My cheap remote canister stove then turned up and with the current hanging plate the new stove fitted very nicely on the base of the canister, but I will point out that at the moment this is just playing with design and I realize that with this system would be difficult to fit a wind shield and pack away.

liquid feed JB PCS stove

The next part of my hanging stove project was to use a JetBoil Personal Cooking System (PCS) with a liquid feed modification that I had done a number of years ago will before JetBoil came out with the Helios I have used my modified JB stove in winter in Australia a few times so I know that it works in cold conditions.

Pre-heat tube

I needed to hang the canister on the base, so I machined up a bracket that screwed onto the plastic shroud, the bracket takes the std JB 100g canister, I did the machining so the canister clips in so it does not fall out while it is still easy to put in, and that it would still fit into the JB PCS pot.

All packed away

I then needed some way to hang the JB stove, I did not want to buy a JB hanging kit as they are expensive here in OZ, so I got a some spare tent poles and some SS wire form the local fishing store and made a rough copy, while the hanging kit is OK for display purposes I would not like to assemble it on the side of a cliff at -20ºC, some more design thoughts needed here.

 

Where to next, as I am not a climber I have been doing some research on hanging stoves to try and understand what is needed, I have also been in contact with a leading British Climber to try and get an understanding of what is needed. So far I have found a few ideas, one is using a larger pot as the windshield, his seems to be very popular and I have seen this done with backpacking stoves, I have also found that my idea of hanging the canister upside down under the stove is not a new, it was done very nicely to a WindPro stove by Longshanks in Denver and the idea posted on a climbing forum last year. http://students.washington.edu/climb/forum/viewtopic.php?f=19&t=5759&start=0

I am combining this project with one that I have been thinking about doing for a while and that is windscreen design.

This project will continue.

Yamame vs a No 4 rod

One Friday evening a few weekends ago, my mate Dave and I backpacked into nice river somewhere in the Australian High country to do some fly fishing, Dave brought along his No 4 and his Tenkara Yamame rod, I had decided to go lightweight and only brought along my Yamame rod. We had planned to fish Friday evenings rise but it was raining heavily so we settled down around the fireplace in an old cattleman’s hut and had a nice evening eating our gourmet takeaway curry and drinking some Port.

 

On Saturday morning we started fishing at about 7.30am, Dave decided to use his No 4 rod and as mentioned previously I only had my Yamame rod. The conditions where just about perfect, it had been raining the day and night before and the river had a good flow in it and we had a slight breeze to our backs, we both tied on much the same combination a small brown dry with a beaded nymph trailing about 30 cm below. After a few casts I hooked up a nice half kilo (1 pound) rainbow, Dave also did not take long for his first. Dave is a fly fisherman who likes to do a bit of bushwalking but I am a Bushwalker who likes to do a bit of fly fishing, in the 6-7 years I have fishing with Dave all but once he has out fished me but for some reason that morning I was doing better on my Yamame, I was catching three fish to Dave’s two. Early on in the morning I was catching the fish up on the nymph but as the morning was passing I started to get more on the March Brown or Royal Wulff dry fly, some where small but most where around half a kilo, a few a bit bigger, all where released.

A nice Tenkara cast

As the temperature heated up things started to slow down, we decided to go back to camp, have some lunch a rest (sleep) and fish the evening rise, I had a tally of around 15 rainbows and browns, Dave with his No 4 had only about 10, I had out fished him with my simple lightweight Tenkara rod, a rare feat.

A nice spot to fish

That evening Dave taking my lead, decided to use his Yamame, we wondered down to different part of the river, Dave started at the middle of a big pool and I started up stream at its head, I tied on a Royal Wulff and on my first cast I caught a nice 600-700g rainbow, at that spot I landed three very nice rainbows, after my second I had decided to move on and had collapsed my rod, the line was still in the water, when I started to pull the line in a nice little rainbow could not resist, I had my third from the same spot and dinner, who needs a rod.

The long pool where Dave hooked and lost a nice 1.5kg rainbow

I continued slowly upstream, after a short time my evening tally was 5, all over half a kilo, I kept one for dinner, expecting Dave to have kept one too, after about 40 minutes Dave caught up to me, he had hooked what he thought was a 1.5 kilo (three pound) rainbow, fought it for a few minutes before it broke him off in the rushes, he decided to move on but when he went to collapse his Yamame, the second and third sections where stuck hard, Dave unfortunately broke the second section trying to release the stuck pieces, he was pssed off, and was especially po’fd when I told him I had five but only kept one, Dave had no dinner, so I loaned Dave my rod, he fished for about ten minutes before he decided that it was not his night, I took over and hooked a very nice rainbow right in front of him, me 21, Dave 10.

After a very nice meal of trout and pasta sitting around the hut fireplace , we finished off the Port and retired ready for a mornings fish, this was to be a different day, we where on the river at around 7.30 again, this time the breeze was coming from up stream, I was finding the fishing hard going, Dave was nailing it, his more powerful no 4 was allowing him to cast much further than I was with my Yamame. We fished until 10.30 am, Dave had 12-13 more and after some very hard work I had only three, in the end we both had caught around 24-25 fish each. It was a real good test putting the No 4 and the Yamame against each other, why did I out fished Dave on Saturday, I have no idea, the fishing gods where with me, but on the Sunday, I had some problems casting into the slight breeze, my fly was not landing well at all, the three fish I did manage to hook where when the wind had died down.

All I can say that in the end neither rod or person was the better, but most important of all, we had a very enjoyable weekend, and the river had been a pleasant surprise.

Dave has just e-mailed me and the new and spare tips have arrived, outstanding service from Tenkara USA.

Tony