Tent stove from a cookie tin

This is another free tent stove that can be made from a cookie or biscuit tin and a scrap of corrugated roofing iron.

Introduction

Previously I have described tiny compact tent stoves that are made of stainless steel and designed specifically for ultralight backpacking in winter.

More recently, for base camp situations, I have made a larger tent stove out of a 20L cooking oil drum. The light mild steel sheet metal makes construction easy. However, it will cause the stove to have a delightfully hot surface for cooking and heating, but relatively short life.

The current stove is of intermediate size. It is made from a tin plate cookie tin (175mm dia) and a scrap of old roofing iron. The stove should be suitable for base camping or could also be backpacked. It is very simple and may make a suitable small stove to try out hot tenting if your budget is zero.

After using the stove for some time now, I realize that I have rather under-sold it as a one-weekend-wonder. With suitable care, it should provide several weekends of intense winter camping pleasure.
Me

A tent stove made A cookie tin and some 'old fashioned' roofing iron that is soft and easy to bend. The tin will become the closed burn chamber. The roofing iron will be flattened and folded to become a 'flame guide' within the burn chamber to divide it into two portions and protect the tin from the intense heat from the downdraft burner. — A tent stove made A cookie tin and some ‘old fashioned’ roofing iron that is soft and easy to bend. The tin will become the closed burn chamber. The roofing iron will be flattened and folded to become a ‘flame guide’ within the burn chamber to divide it into two portions and protect the tin from the intense heat from the downdraft burner.

The cookie tin tent stove

A tent stove made from a cookie tin. "No pretty roses now as the stovetop reached 400C+. Inside the tin, the 'flame guide' (a dividing wall) fits between the two holes in the cooktop and extends across to the other side. A cut-away at the near end of the guide allows the flame and hot gases to turbulently pass through the hole to provide mixing and good clean combustion. This action forces the wood gas flame to spread out under the stovetop and exchange its heat efficiently with the surface of the burn chamber. — A tent stove made from a cookie tin. “No pretty roses now as the stovetop reached 400C+. Inside the tin, the ‘flame guide’ (a dividing wall) fits between the two holes in the cooktop and extends across to the other side. A cut-away at the near end of the guide allows the flame and hot gases to turbulently pass through the hole to provide mixing and good clean combustion. This action forces the wood gas flame to spread out under the stovetop and exchange its heat efficiently with the surface of the burn chamber.

Burn chamber

This tent stove needs two 40mm diameter holes cut in the cookie tin lid. Elsewhere, hand cutting methods are described if you are not lucky enough to have a suitable punch for this job. One hole is for fitting a stove pipe and the other receives a short fuel stick holding tube that becomes a downdraft gasifier when the stove is lit.

A tent stove made from a cookie tin. The two 40mm diameter holes have been cut with a space of about 25mm between them. This allows a wall or 'flame guide' to be placed between them within the stoves combustion chamber. — A tent stove made from a cookie tin. The two 40mm diameter holes have been cut with a space of about 25mm between them. This allows a wall or ‘flame guide’ to be placed between them within the stoves combustion chamber.

Tent stove flame guide

The flame guide can be made from scrap roofing iron. Old fashioned iron is relatively soft and easy to work with. Modern roofing iron is much harder and brittle and is much harder to work.

With this cookie tin tent stove design it was simple to extend the ‘foot’ of the flame guide and cut a curve on it to fit across the entire bottom of the large (and hottest) compartment of the combustion chamber. It holds the flame guide securely and provides some insulation to the bottom of the stove hottest first chamber.

The enlarged flame guide foot also can act as a heat sink for the hottest parts of the guide (when covered with an insulation layer as described next) and thereby extend it operational life.

At the end of the the flame guide that will be placed directly below the down draft wood gasifier (left end) the charcoal combustion will reach 1,000C+. I have added a scrap of iron to the flame guide to form a curved wing that will protect the wall of the cookie tin from the high temperature and strongly oxidizing conditions that occur in this zone.

A flame guide that is made from roofing iron scrap. It fits tightly inside the cookie tin combustion chamber and separates the fuel port from the exhaust port to make the burning wood gas travel a long path through the burn chamber. The cut-away corner (top left end) allows the flame and gas to pass turbulently between the two chambers to mix air with the wood gas to complete the clean combustion and optimize the heat exchange to the stove surface. A scrap of iron attached to the flame guide forms a curved wing that will protect the wall of the biscuit tin from the high temperature and strongly oxidizing conditions that occur in this aggressive charcoal combustion zone. The wing is attached to the flame guide with a rivet that is made from a flathead nail. — A flame guide that is made from roofing iron scrap. It fits tightly inside the cookie tin combustion chamber and separates the fuel port from the exhaust port to make the burning wood gas travel a long path through the burn chamber. The cut-away corner (top left end) allows the flame and gas to pass turbulently between the two chambers to mix air with the wood gas to complete the clean combustion and optimize the heat exchange to the stove surface. A scrap of iron attached to the flame guide forms a curved wing that will protect the wall of the cookie tin from the high temperature and strongly oxidizing conditions that occur in this aggressive charcoal combustion zone. The wing is attached to the flame guide with a rivet that is made from a flathead nail.

Fitted flame guide

The flame guide should be made to just squeeze into thecookie tin by stretching the circular opening a little to allow the guide to clear the beading that is formed around the opening of the tin. A slightly oversized flame guide can simple trimmed to fit perfectly.

The flame guide fitted in the biscuit tin stove. The small fold on the top of the flame guide wall can be bent more or less to make a close fit with the underside of the lid. — The flame guide fitted in the cookie tin stove. The small fold on the top of the flame guide wall can be bent more or less to make a close fit with the underside of the lid.

Alternative flame guide sheet metal

If the stove is intended for backpacking the flame guide could be made out of a much lighter tin plate from a discarded food can or stainless steel from curbside rubbish as shown below.

Abundant free stainless steel sheet from from curb-side hard rubbish.

Soil and ash base cover

The base of the burn chambers can be covered generously with sand or soil and ash to provide insulation for the bottom of the stove. As the burn progresses, a deeper layer of ‘fluffy’ ash will form and this will add to the insulating effect. The insulation of this layer causes more heat to be distributed to the stovetop and less heat to be transferred to the bottom of the stove.

A tent stove made A biscuit tin and some 'old fashioned' roofing iron that is soft and easy to bend. The tin will become the closed burn chamber. The roofing iron will be flattened and folded to become a 'flame guide' within the burn chamber to divide it into two portions and protect the tin from the intense heat from the downdraft burner. — A tent stove made from a cookie tin and some ‘old fashioned’ roofing iron that is soft and easy to bend. The tin will become the closed burn chamber. The roofing iron will be flattened and folded to become a ‘flame guide’ within the burn chamber to divide it into two portions and protect the tin from the intense heat from the downdraft burner.

Stove base insulation and thermal mass

The heavy soil component of the above-described insulation layer has other benefits. It gives an otherwise very light stove thermal mass. This means that it will make the stove burn better during fueling ‘glitches’ and also recover quickly when refuelling is neglected.

There is a very slight negative impact in that this extra thermal mass makes the start-up-from-cold a little less delightfully fast than my stoves without much mass. However, the gain in the robustness of the combustion more than offsets this small loss.

[Add a video of cookie tin stove start-up.]

A view of the bottom of the cookie tin tent stove after a protracted burn. The paint has been singed, but the thick soil and ash layer within the burn chamber has protected it from total destruction.
The layer provides considerable protection to the stove bottom and in doing so it reflects more heat to where it is most needed. Also, the soil gives the stove a lot more thermal mass to maintain the stove pipe draft. This means that it will make the stove burn better during fueling 'glitches' and also recover quickly from refuelling is neglected. "Another low mass tent — A view of the bottom of the cookie tin tent stove after a protracted burn. The paint has been singed, but the thick soil and ash layer within the burn chamber has protected it from total destruction.
The layer provides considerable protection to the stove bottom and in doing so it reflects more heat to where it is most needed. Also, the soil gives the stove a lot more thermal mass to maintain the stove pipe draft. This means that it will make the stove burn better during fueling ‘glitches’ and also recover quickly from refuelling is neglected. “Another low mass tent stove that can have mass added when the carrying is done”

A tent stove made from a biscuit tin. It burns cleanly and efficiently (~400g of stick per hour) to provide generous tent heating and cooking and cost nothing. — A tent stove made from a cookie tin. It burns cleanly and efficiently (~400g of stick per hour) to provide generous tent heating and cooking and costs nothing.

Size matters

When compared with my benchmark’ KISS tent stove (137mm dia) the cookie tin stove was a little slower to start up. I think the extra thermal mass of the heavy flame guide and soil plus ash base layer was the cause of the slowness, but it was not a problem.

On the other hand, the extra mass was a great benefit for burner stability after startup. “All good”. The cookie tin stove produced lovely trouble-free warming heat and could slowly boil water. However, when compared with my KISS tent stove, I could tell that the larger cookie tin (175mm dia) was less powerful. Or maybe more correctly, it had less intense or concentrated heat for cooking and radiant heat for warming bodies. “Nevertheless, this cheap and hot tent stove would be a good first try at hot tenting.”

A large cookie tin tent stove- finding the breaking point

“In a funny way, I don’t consider an idea has been properly explored until the breaking point is found!” Consequently, I made a larger cookie tin stove (240mm dia, shown below) to see what would happen.

A larger cookie tin (240mm dia) that is soon to become a tent stove.

[Add a photo of large cookie tin stove]

When compared to the ‘benchmark’ KISS tent stoves cooktop area, the cookie tin cooktop area ratios were 1.6 and 3.1 respectively for the small and large tins. Consequently, I expected that when using the same burner and stove pipe combination on these different sized stoves, this large change in the relative area would make the larger stoves run progressively less hot.

The poor heat conductivity of the stainless steel of the KISS tent stove is likely to be another contributing factor that makes it have a higher radiant heat output (Glows quite red in the dark.) rather than conducted and convected heat output. This at first may seem counterintuitive. However, I discuss this in my post on micro tent stove design for strong radiant heat and robust draft.

The following night time photos should provide a simple visual indication of the relative radiant heating power of the three stoves. (I have not directly measured temperature on all three stoves on a fair comparative test. I will do so and add the results when available.)

The photos below were taken to show each stove at its peak temperature performance. I think you could imagine which stove you would like to have near you in a small tent in a snowy winter wonderland. “I know I can. However, I think you could also imagine that any one of them would be welcome in the tent.”

The 240mm diameter cookie tin tent stove. — The 240mm diameter large cookie tin tent stove made of mild steel.

A tent stove made from a cookie tin showing off its heating power at night time. — The 175 mm diameter cookie tin tent stove made of mild steel.

The fuel/burner tube in the kiss stove is shown supporting the bush fuel sticks. This short vertical tube is acting as an inverted J-burner that creates an intense source of heat from the fire dome for warming winter trekkers and cooking. It only burns about 400g of sticks/hour. "Who cares if it is only a quasi gasifier." — The 137 mm diameter KISS tent stove made of stainless steel.

Stove metal- a confounding factor

Apart from the increased stove size in the above comparison, the stainless steel of the KISS tent stove is much less conductive than the mild steel of the tinplate of the cookie tins. I think this difference may also be another contributing factor that makes the smallest stove hotter than the others. This, at first, may seem counterintuitive. However, I discuss this in my post on micro tent stove design for strong radiant heat and robust draft.

Conclusion

This cookie tin tent stove is quick and cheap to make and with care, it should provide several weekends of hot tenting. Keep the stove small (175mm or less) to get the best heating power and the fastest cooking. It should give you a taste of hot tenting pleasures. You may get hooked and wish to make make a hotter, lighter and more compact KISS tent stove that backpacks easily within its own pots and can also turn into an outdoor fast cooking blower or alcohol stove and have a much longer service life.

Tim