Build a Rocket Stove, Girls!

On Saturday afternoon, we were delighted to host a Rocket Stove building workshop. This was run by Jen and Tom, and taught us how to create these amazing fuel-efficient stoves which can be made with readily available waste items and a few simple tools. The guys who had booked on the course couldn't make it, for various reasons, so an all female team of trainee rocket-stove builders set too, and managed to make 3 separate stoves, proving that they can be made by those without a huge amount of muscle, or practical metal-working experience.

Here's how we did it!

First Jen and Tom explained the basic principles of the rocket stove. The aim is to create a small fire in a confined L-shaped space with good airflow. The shape of the space also helps, as it draws the fire up, meaning that only the tips of the fuel burn and the gases from the fuel are also burned, which gives a pretty much smoke free fire with minimal residue. 

Step 1: Remove the top of the can 

Step 2: Press in any sharp edges, and clean
out any remaining oil

Step 3: Cut out some sections of can with tin snips, to create
flat plates of metal.

(Some of the group made a much neater job of step 3
than others. This is Jo's reaction to seeing our sheet!)

At this point, you'll notice that there were 2 different patterns of chimney being constructed. This is because one aim of the day was to create a long-lasting stove for Windmill, which meant it was created using a round tubed "ceramic elbow" which will contain the burn area and be more robust in the long-term than the other stoves. Those stoves were created with square-profile elbows which will last for a few years before becoming brittle and needing to be replaced.

Step 4 - round version: Those metal plates were bent around
the ceramic elbow and riveted to create tight-fitting sleeves
for each end.

Step 4 - square version: The metal plates were bent around a
square fence post of appropriate dimensions then cut and
riveted to create an L-shaped chimney with a square
cross-section.

Step 5: Make a hole around 10cm from the base
of the can that the foot of the L-shaped chimney
can slot into.

Step 6: Cut a wind-baffle from another can which
holds your pan just a few centimetres above the top
of the chimney. Cut a hole in the end of the can to
make a slot for the top of the chimney to fit into.

Step 7: Slot the chimney into place and make sure it stops
about level with the top of the main can.

Step 8: Fill the void in the can with vermiculite to provide
a non-flammable insulation. This ensures the heat is retained
in the chimney and means that the sides of the stove stay very
cool, allowing for easy handling of the stove when lit.

Step 9: You have to squint to see this one! Make a "bridge"
that will sit in the bottom end of the L to keep the fuel high
enough to ensure a good flow of air into the stove. The
round chimney stove had a specially made ceramic version.

Step10: Make sure everything fits!

Step 11: Test firing. Another can provides a
useful increase in height to cooking level.
Marvel at the lack of smoke - yes the stove
really was already lit at this point.

Step 12: Eat the freshly-made popcorn!

You do have to make sure you keep tapping the ends of the fuel sticks so that they move forwards as the ends burn away, otherwise the fire goes out, so this isn't a stove to light and then leave to its own devices as you prepare the food. It's not too difficult to keep going though, as long as you just fiddle with it regularly. 

Apart from all the other great features of the rocket stove, the thing that really appeals to us is that it's just the right size for us to use our coppiced willow in it. With any luck, most of our cooking will be carbon neutral from now on. Thanks to Jen and Tom, and the folk that helped them deliver all the kit. We've had some really positive comments about the course, and those who got to take away a stove were delighted with them. We look forward to hearing how they have performed as well.