It boiled a full billy (approx 1.7 litres) in about 10 mins I think. I wasn't really timing it and could be way out. I basically lit it and got it going nicely then topped up the fuel and popped the billy on. The one fuel load boiled the billy and I think kept a rolling boil for a while. To top up fuel you can poke bits inbetween billy and stove top but it is easier to lift the billy, it's so stable that this isn't a problem. Any ash just dropped down through the larger mesh into the base but there wasn't much at all, pretty much everything was consumed, including a lot of cider hence the vagueness.
I never noticed any sooting on the inside of the jacket but I've only played with it once or twice. The only mod I've planned and that was sort of there from the start is to make a sliding cover for the air entry slot at the bottom to allow the airflow to be restricted and reduce heat output.
I'll have a slightly more scientific and less drunken play at the weekend and post up the results.
Cheers
Grebby
Right, I eventually got round to actually timing stuff. I went with 1 litre of water and discovered my guestimate was WAY out. I lit it and it basically took 2-3 mins to get going really well. I then topped it up with long upright split wood (pencil thick to just over 1cm square) a bit shorter than the length of the basket and popped the billy on. I discovered that the long stuff burned very quickly and had to top it up about 4 mins later. This time I used shorter fuel and basically put as much in as possible placed across the basket. this lasted longer but it took another top up before the water boiled. Boiling took 15 mins from putting the billy on but did keep a rolling boil for about 5 mins more.
The ash left was minimal and had dropped into the base. I could pick up the stove with a riggers glove on without any heat issues and there were only a couple of small (approx 1cm cubed) coals left in the basket.
I still need to sort out some form of wind shield for it but I think it works OK. Thicker fuel may help burn times but I'll have to see. The only annoying thing is having to lift the billy to top up fuel but it's not that bad
I've added a few pics of it lit to the picasa web album
Here. The pic of the wood shows the long length and the short lengths were basically half this length.The laplander is there for scale and cutting the stuff up
. I probably went through 1.5 to 2 times as much as is shown in that pic.
Cheers
Grebby