SUL 24.8g liquid feed canister stove.

This is a little stove that I made last week, it is a liquid feed canister stove with a total weight of 24.8 grams (0.875 ounces) and that includes burner/ pre-heat tube (6.4g), valve (7.5g), pot stand and windscreen (7.1g), fuel line (1.9g), pie tray for top windscreen (1.9g).

The stove is designed to fit into a BPL Ti 550 pot. The complete stove and pot/bag weighs in at 84.4g

The pot stand design is based on designs that I have seen used with alcohol stoves and is made from bird wire, the base is from the bottom of a Fancy feast cat food can, the windshield around the pot stand is from a beer can and the top windshield is from a pie tray. The burner was machined from a round piece of aluminum bar, the burner plate from Ti and the pre-heat tubes is made from 1.6mm OD hard drawn Stainless steel tubing with a fitting made from brass to screw in to the burner, the valve is adapted from my 14.2g canister stove and fits on a STD canister but I am planning to make a SUL valve to use with Coleman Max canisters.

Initial performance is promising I did two tests, one slow 12 minutes and one fast one 5m 30s, the slow test used 5.5g of fuel to raise 500ml of water 80ºC and the fast test used 6.2g to raise 500ml of water 80ºC.

Future improvements: I hope to reduce weight a bit further maybe get under 20g, Pie tray is a bit flimsy, will work on that later, as mentioned above a I plan to make a valve to use Coleman Max canisters.

I am planning on using this stove as my main stove for all seasons.

Tony


550 pot on SUL stove


SUL stove all parts


SUL stove in pot


SUL stove top view


SUL stove under test


SUL pot with top windscreen in bag

Edited by tbeasley on 06/09/2008 21:41:14 MDT.

You keep raising the bar, Tony. Very nice!

I'm curious about the burner diameter, the flame pattern, how it would work with a larger pot, and when you'll have the components ready for sale. I can handle the cat food can.

Tony
Sub 25g ? Wow, I would be happy with a 100g liquid feed stove , especially around that size .
Have you thought of trying a Caldera Cone with gas ?
Maybe it would work on your low setting (?)
Franco
(The clearance between the bottom of the 550ml pot and the base of the cone is 9cm)

Edited by Franco on 06/10/2008 01:19:41 MDT.

Hi Tony,
Wonderful, thanks.

Edited by vagabunjp on 06/10/2008 01:46:48 MDT.

...thats left me speechless Tony

Thanks to everyone for the comments

Hi skots,

>I'm curious about the burner diameter, the flame pattern, how it would work with a larger pot, and when you'll have the components ready for sale. I can handle the cat food can.<


The burner diameter is 21mm below are some pictures of the flame under the 550 pot, the flame coming out of the burner and the flame under a 1l Ti pot. which is the pot that I normally use when walking? The stove is also designed to fit under a modified PCS JetBoil pot. The stove will work very well under larger pots as the greater the burner to pot diameter ratio the higher the efficiency is.

I am unable to make these stoves to sell, they take 30-40 hours to make, you can work out how much I would have to charge to make some money.


Hi Franco,

>Sub 25g ? Wow, I would be happy with a 100g liquid feed stove, especially around that size .
Have you thought of trying a Caldera Cone with gas ?
Maybe it would work on your low setting (?)<

I have thought of using my low profile stove under a cone, I am planning to make a SUL low profile version soon
http://www.backpackinglight.com/cgi-bin/backpackinglight/xdpy/forum_thread/9564/index.html?skip_to_post=68819#68819
unfortunately I would like to make my own cone and the materials are hard to get in Australia

Tony

Flame under 550 pot

Flame out of burner

Edited by tbeasley on 06/10/2008 04:13:15 MDT.

Thanks Tony.
I wanted to post during those magical hours when only Aussies get to play. Since the cone, even in Ti, would add weight , I could end up being excommunicated by those super ultralight extremists.
My reasoning was that it could possibly last longer than your stand and wind shield, and trap more heat and be a bit more klutz proof. Not that the few grams of gas per day saved would make up the extra weight.
( BTW, I think that a good part of the efficiency of the Cone is due to the heat transferred from the cone itself to the pot).
As much as I am amazed at your achievement, I am thinking of a lightweight solution for myself.....
Bunnings have some aluminum flashing that could provably do , it needs to be 18cm high , but from memory it is about $50 for the shortest length.
Franco

Franco,
I get aluminium flashing from mitre 10 in SA for under $5 a metre, let me know and I can send you some over. Sorry to hijack the post, back to the stove, nice stove Tony, nice stove.

Edited by bretthartwig on 06/10/2008 06:16:32 MDT.

Hello Tony,
That's very impressive.
One thing that occurs to me. You know Roger Caffin's inverted liquid fuel stove design showed that the preheat tube did not have to be in the flame, it could just be warmed by conduction. I wonder whether you could save weight by wrapping a shorter preheat tube against the burner lower down. This should be shorter, and therefore lighter, Because it will never get very hot it could be made of a different lighter material, and it would leave the flame for heating water and just use waste heat to gasify the gas so might be fractionally more efficient

Excellent work. I would agree with Tony however in terms of taking a cone into consideration if for no reason other than stability.

ps - I like the lab workstation running the Apple iMac ; )

Very nice Tony. Excellent choice for your main stove for your walkabouts.

How does the burner maintain it's verticle position, does it have a base?

Hi Franco,

Thanks for your suggestions. I have been down to the local hardware shops and measured the thickness of everything that remotely looked like it could be used in stove making including the flashing, the flashing that I saw was much thicker than what I wanted 0.3mm and it is too soft, the cones are made from hard or stiff aluminum, I actually have some soft 0.13mm embossing foil which would be ok to play with for cone making but would not be much good for long term use, I am thinking about getting some Ti sheet which could be a bit thinner still. I have done some gas flow research to try and understand how the cone will work with a canister stove burner, getting the hole design right is very important.

Tony

Hi Derek,

>You know Roger Caffin's inverted liquid fuel stove design showed that the preheat tube did not have to be in the flame, it could just be warmed by conduction. I wonder whether you could save weight by wrapping a shorter preheat tube against the burner lower down.<

I tried Rogers idea (picture below) it did not work as well as the pre-heat tube and it came in a bit heavier, it needs some more development work.

Tony

Tony
The flashing was only meant to test the behavior of the cone, I definitely agree with you that it is too soft for practical use. When I tried a tighter cone type wind shield with my gas stove I had a lot of problems with air turbulence (?) within, but I have no knowledge on how to fix that apart from trial and error.
I would think that in he long term the titanium foil that TiGoat use for their Caldera Cone is hard to beat. Very flexible,strong and light.

Brett
Thanks for that. I will check again with Bunnings because they just opened up the road from me. But it would be just to work out a pattern anyway.

Franco

The SUL stove is now 23.5 grams, I found this weight loss by using a different thinner fuel line that has a higher temperature rating and machining some excess weight off the valve, sub 20g is coming closer. The pot stand is a bit week under a full 1l pot, so a slightly heavier stand will be needed but I expect only 1-2g heavier

Burner and pre-heat tube 6.2g
Pot stand and lower windshield 7.1g
valve 6.9g
Fuel line 1.2g
Top windscreen 1.9g

Tony


23.5g SUL stove


Parts

Hi Tony

Unreal!

The copper rod heat exchanger is rather long and rather close to the jet: I suspect these factors may be a small problem. Perhaps if you start the stove with the canister upright for 10 - 20 seconds, then invert it? I am thinking in terms of priming the stove with some preheat.

Perhaps if you make the air-mixing column a bit shorter and the burner head a bit large, with some mesh inside the head to help mix the gas, you could reduce the height of the stove?

That plastic fuel hose worries me though. VERY badly. When the stove gets hot after a while the plastic around the coupling will soften. I find that the coupling starts to leak a very faint trickle of gas, and eventually that leak catches alight. OOPS!

I still say UNREAL!

Cheers
Roger

Hi Roger,

>The copper rod heat exchanger is rather long and rather close to the jet: I suspect these factors may be a small problem. Perhaps if you start the stove with the canister upright for 10 - 20 seconds, then invert it? I am thinking in terms of priming the stove with some preheat.

Thanks will look at.

>Perhaps if you make the air-mixing column a bit shorter and the burner head a bit large, with some mesh inside the head to help mix the gas, you could reduce the height of the stove?

Thanks again will try your ideas this weekend.


>That plastic fuel hose worries me though. VERY badly. When the stove gets hot after a while the plastic around the coupling will soften. I find that the coupling starts to leak a very faint trickle of gas, and eventually that leak catches alight. OOPS!

Roger you are right here, and thankyou for pulling me into line, I have been too focused on the weight factor not safety, I will re-access my fuel line/ pre-heat tube designs it will only add a few grams at most to lengthen the Pre-heat tube and use PFA tubing.

Tony

Hi Tony

> That plastic fuel hose worries me though. VERY badly.
> Roger you are right here, and thank you for pulling me into line
I would prefer to think of it as pulling you OUT of the (fire) line :-)

> only add a few grams at most to lengthen the Pre-heat tube
Definitely a good idea - and you canb then stick a brass rod up it too.

> and use PFA tubing.
And maybe some SS braid and a crimp over the lot at each end?

If you want to lend me the stove at some stage I can run a CO test on it for you too.

Cheers
Roger

Very cool stuff!

HJ

Jim
Some more interesting stuff from Tony here:
http://tonysbushwalking.wordpress.com/
Franco