Month: April 2008

As a relatively recent convert to hydration systems, or platypi (it seems Platypus is to hydration what in British English, Hoover is to vacuum cleaner) I’ve had to learn how to look after them when they are not being lumped about in my pack.

It might sound strange that they need any “looking after” at all, but they do. Or else you end up sucking mildew flavoured water through a black spotted tube.

The usual handy hint to prevent that is simply to store them in a freezer. But in a small kitchen, with a very small freezer, the food has to get first priority. So no freezing for our platypi except in-use on the hill (for which a neoprene cover, that covers the bite-valve, combined with blowing back into the bag, works very well for preventing a freeze-up even at minus-a-lot Celsius).

So I’ve got in to a very simple routine for making sure they stay mould free:

When you get home, fill the bladder with really hot water from the tap. Not from a kettle. It might work, I’ve not tried it, but I have a feeling that boiling water would damage the bag (anyone know different?). But use very hot water never the less.

Hold the bag above the sink and squeeze the bite valve until a lot of really hot water has had a chance to clean out the tube. It needs to run for a good ten seconds I reckon, since the first run through the pipe will cool by the time it gets to the bite valve.

Then drain it out and shake out the excess drops of water.

The last trick relies on having a bite valve that will pop off easily, or at least dissemble without too much of a struggle (like the Source variety – whose bite-valves I favour) and a bag that opens at the opposite end from the tube (like a Platypus Big Zip or Source Widepac): Remove or dissemble the valve to get a good airflow up the tube, stick the tube out of a window (perhaps a second floor window, in case you forget its open and leave the house!) and prop open the bag with something.

The breeze blowing through the window will get pushed up the tube, and usually dries the bag in a few hours even on a still day.

With a bone-dry bag, there’s nowhere for the black mould to grow – and you get a happy, healthy platy.

I’ve been experimenting with alcohol stoves for a little while and to be honest, of the four I’ve tried, only one puts out enough heat for two people’s food: The White Box

Named for the white box that it comes in, it’s a very simple and robust little stove. There’s plenty of information about them on the Internet already so I’ll concentrate on how efficient they are and how I’ve been able to use mine down to -10 Celsius (14F). It’s often said that you can’t use an alcohol stove in freezing conditions, but with a little care, you can.

I’ve wanted to replace my old faithful MSR Whisperlite Internationale with a lightweight alcohol stove for a while but to be honest I’ve so many other things going on, I don’t have time to fiddle around making my own. Besides, from what I’d read, unless you get your design and build dead right, they can be rather inefficient. So I thought I’d buy a couple from people who make them all the time.

I tried a beautifully made Penny Stove from The AC Aircraft Company (Bill doesn’t seem to show them on his site now for some reason). But the heat output never managed to boil the 900 ml (about two pints) of water I want to use for porridge + tea in the morning or rehydrating buckwheat pasta + soup in the evening.

I then tried a Sith from Tinny at MiniBull Designs (his blog is always fascinating). It struggled to maintain enough heat in the presence of a cold pan of water to even stay alight. Tinny and I never did get to the bottom of this – it may be that “normal” methylated spirits in the UK haven’t got as high an alcohol content as something like Heet in the USA (I am just guessing here – anyone know for sure?). Even holding the pan above the stove a couple of centimetres never allowed the water to boil before the fuel ran dry.

So I ordered an Atomic from him. And with its pot-stand it managed to pack enough of a punch to get the water hot, but still not boiling.

At this point I gave up for a while. But listening to Bob on one of his podcasts singing the praises of the White Box made me decide that it was worth one last go.

And I’m very glad I did. The White Box is very small, tough and light; 68gms. 30 for the stove, 10 for the aluminium square it stands on and 28 for the wind-shield.

Critically, it can boil my required amount of 900ml of water in about nine minutes from sparking up to rolling boil. Slower than the MSR, but a lot less dangerous for cooking in the porch of a tent.

I’ve cooked in the porch with the MSR, but no matter how much the rain was falling and the wind blowing, I’ve always sparked up with the door wide open and only zipped back up once it’s settled to it’s usual fearsome jet of blue flame. LB has had to hold on to the sides of the tent to stop wind damage caused by leaving it wide open in a hooley a couple of times. (I know I could light it outside and carry it inside carefully – but where’s the fun in that?)

Great – so it works and it boils lots of water. But how do you get it working in the cold?

The critical point is to make sure that both the alcohol and the stove itself are warm by keeping them within one thin layer of your skin for about ten minutes.

I keep the alcohol in a small MiniBull Fuel Bottle (the AG fuel bottles that Winwood stock look very similar). It’s important to have a small amount so it’s easy to heat.

When I wake up, I grab the bottle from the tent pocket I put it in the night before and stuff it inside the sleeping bag but outside the silk liner. At -10C that’s a bit of a wake-up call but with a quick fumble you can keep it away from you whilst it warms-through enough to allow it to come closer to your skin.

Once I’ve got most of the cooking stuff together, but before I fill the pan with water and get out the porridge, I throw the stove itself inside the sleeping bag to let it warm-through as well. It doesn’t take as long since it’s a small hunk of aluminium.

In the evening it’s similar, keep it between your down jacket and your t-shirt. Though when wearing a 260 weight Icebreaker long sleeved T (expensive – but worth every penny) I have to finish by keeping it right next to the skin. Otherwise the merino just wouldn’t let it warm up enough.

Once you’re completely ready to start cooking, pan filled and fire-steel waiting, whip them both out, fill the stove and spark up.

Then, hold the pan of water (or ice slush if you have it) a couple of centimetres above the flame. That way you’re letting the stove prime as usual whilst also “priming” the pan of cold water. Otherwise, even though the stove might have blossomed to its beautiful chrysanthemum of flame, the cold pan can suck the life out of it.

Nine minutes or less later, a couple of pints of boiling water enthusiastically fills your porch with steam.