The Last of the Alcohol Stove Accessories: Windscreen and Fuel Bottle

In this post and this post we made an alcohol burner to use as a backpacking stove. We’ve also made a snuffer and a pot support. But before we can call this stove project done enough to play with, we need to make a windscreen, and find a fuel bottle. I promise after this we’ll get to set it on fire!

Obligatory Safety Warning

We’re going to be cutting bits of thin aluminum sheet. The cut edges are likely to be sharp, and could cut you. Be careful! Also, tools are sharp too. Or pokey. Or smashy. They could hurt you too. Be careful! Also also, some or all of the tools and materials involved are known by the state of Cancer to cause California. If you follow these instructions and cut off your legs, don’t come running to me.

The Windscreen

Alcohol stoves need good windscreens. They operate at lower pressures compared to butane, propane or gasoline stoves, so the flames get blown about very easily, and the heat goes with them. Even fairly light wind will render an alcohol stove useless unless it can be shielded somehow.

Tools and Materials

The only material is a piece of heavy-gauge aluminum foil. I used the disposable foil cover for a steam table pan, but anything similar would be fine. Ideally you want something heavier than the usual kitchen foil, but even that will work for awhile if you can’t find anything better.

For tools you need a straightedge that’s fairly long, and a means of measuring. An ordinary yardstick would work brilliantly (or a meter stick, if that’s all you have). You’ll also need a marker, and scissors. Don’t use Michelle’s good fabric scissors if you value your hide. A sharp knife of some sort would work too, though you’ll have to be careful about the surface you’re working on if you use a knife.

How big should it be?

The windscreen needs to wrap around the pot and pot stand, and you need enough excess on the ends to make a lap joint to hold the screen in its circular shape. Our stove design seems to work most efficiently if there is about a 1/4″ gap all the way around between the pot and the windscreen. So you can measure around the pot, add 1/2″, multiply by pi, then add a couple inches. Or you could wrap the foil around the pot, expand it by eyeball to achieve the desired gap, likewise eyeball enough overlap on each end to make the joint, and get on with it. Your choice, really.

As for height, you want the windscreen to be at least a little taller than the pot stand. But you also want to be able to roll it up and store it inside the pot while you’re hiking, so judge accordingly. Then add half an inch, as you will be rolling over the edges to make them a bit safer.

Cut it out!

Now that we know how bit it needs to be, we just cut out a rectangle that size from our foil. Since you’ve manage to follow along in the project this far I’m confident I don’t need to tell you how. I did add a picture, though, in place of the thousand words.

We’re still not done though. The alcohol stove needs some air to burn, and we’ll provide that by making a triangular vent hole where the ends of the foil join together. We’ll just cut an isosceles triangle on each end, making sure they’re both on the same long edge (hereafter referred to as the bottom edge).

The triangles should be about 1.5″-2″ on the two equal sides. As usual with this project, precision isn’t important.

You got to know when to hold them, know when to fold them…

First up, we need to fold over the top and bottom edges so we don’t cut ourselves. We’re going to make a 1/4″ fold, which explains why we cut the rectangle 1/2″ too tall.

Once you have the edge folded over, squeeze it between the straightedge and the bench to form a nice crease.

Repeat on the other edge.

Now let’s make the lap joint. This allows us to hook the windscreen into a circle in use, but is easily undone so we can roll up the sheet to carry it.

All we have to do for this is fold the ends, but in different directions. The end result is a really stretched out S shape. Make the folds about an inch wide (remember adding two inches to the length of the rectangle? This is why we did that.)

And that’s it for the windscreen. Assemble it, and enjoy!

The Fuel Bottle

The fuel bottle is just a discarded Coke bottle that I rinsed out. It’s actually one of the smaller sized ones. I think it’s twelve ounces, but I’m honestly not sure. I got it out of a recycling bin and washed it out. I’m filling it with alcohol, so I shouldn’t catch the cooties from it.

Wait, what?

I wanted a Coke bottle specifically, because of its unique shape. I figured that with a clear liquid instead of brown and a missing label it would be pretty obvious that this wasn’t to drink. That’s important, since denatured alcohol is poisonous.

But just to be sure, and to not leave unlabeled chemical bottles around (I’ve heard that’s bad), I made up some labels. I’ve attached a PDF file below if you want to use them. They print on Avery 8160 labels, or equivalent.

You’ll need fuel, of course. You can find denatured alcohol at home improvement stores, paint stores, and hardware stores. In a pinch, get a yellow bottle of HEET automotive gas line antifreeze. It’s the same thing, just more expensive, and you can find it at just about any gas station except maybe the deep South.

And with that we’ve got a complete stove system. Next Wednesday we’re going to light it on fire! Tune in and see if Walt keeps his eyebrows!