So you want to build an alcohol stove do you? Well I was faced with this same question a little over a year ago after my son won a Pepsi can alcohol stove at a Scout Fair. I was impressed with the weight but it lacked what looked like any type of self contained useable system so I began to research the topic. For a great resource I would suggest Zen Stoves.
I will save you hours of searching for a stove design and all accompanying items that make the stove a useful tool. It is not just the stove but also the pot, pot stand, windscreen and other pieces that make the system I will describe into a complete cook system. I have used it many times on day hikes as I got tired of eating a sandwich at the summits and wanted more. I have taken it on 4 day backpack trip as my sole cooking setup and been very pleased. When combined with freezer bag cooking you have an ultra reliable and ultra simple system. Best of all, your complete stove and cooking set will weigh in at about 5 oz!
I want to stress that I did not invent any of this. I have taken many peoples different ideas and refined them into this stove system. I have spent hours in my garage on rainy days testing different ideas and concepts to develop this system. There are plenty of ideas out there that sound good and even look impressive but when tested fail miserably.
The Stove and Fuel:
After much research I chose the Super Cat alcohol stove for my design. Please view this link as it provides everything you would want to know about the stove, how it works and excellent instructions on making one. I have used them with holes made from a hole puncher at ¼ inch as well as ones with holes at 3/16 inch from a Whitney punch as described. Both work just fine but I prefer the 3/16 holes as my testing proved a faster boil and less wind interference. While several variants are discussed I just use the basic supercat. I chose it because it was simple to make, does not require a pot stand or priming pan and you can easily see how much fuel you have added to it. Make sure to use the 3 oz. Fancy Feast or potted meat can as the flare fits the pot I recommend perfectly. He also provides lots of great information on fuels. I just stick with SLX Denatured Alcohol from Home Depot but I have used the Ace Hardware house brand and had identical results.
There is plenty of info out there to overwhelm you. While you can spent over $60 for a lightweight titanium mug to cook in I have found that a $3 25oz. can of Heineken works perfectly, and you get to drink the contents as well! This can is better than the large Fosters can as it is more sturdy due to the shape and the bottom fits the supercat stove better when built with the Fancy Feast cat food can. All you need to do is use a side cutting or safety can opener and remove the top of the can. It can be a little tricky and some openers work better than others. Save the top you removed for a lid or a little heavier but a great fitting lid is the top from an Altoids Citrus Sours can.
One of the reasons this pot/stove combo works so well is that the thin wall pot absorbs heat all the way up the sides giving a much larger surface area to conduct heat through. There are many people out there that like to wrap their pot with fiberglass wick or other non flammable material to keep from burning their hand when grabbing the pot. I have wrapped one with a fireproof blanket I trimmed down to cover a 2 inch wide section of the middle of the pot and as I had expected, my boil times went way up. While the fireproof material is cooler to touch, it takes away pot surface area that was transferring heat. My suggestion is to either wear a glove or use a handkerchief to keep from burning your hand on the hot pot.
The alcohol stove has a drawback in that it performs very poorly with any type of wind. To counter this you need a good windscreen. For lots of background on windscreens and other wind devices visit here. One can be easily fabricated from thin aluminum roof flashing available at your local home repair store. I use some stuff I picked up at Home Depot although I had to buy a 25 ft. roll. I get the 8 inch wide roll as it covers both the stove and pot. To fabricate, simply cut enough off the roll to form a 4 ½ diameter circle with about a ¾ inch overlap (about 16 inches of material). A good pair of scissors will cut this just fine. Slightly round the corners once cut.
Along one of the long sides of the flashing you will need to punch some holes so your stove can get air to keep burning. Get out your hole punch with ¼ holes and proceed to punch holes on ½ inch centers all along one side about ¾ inch up from the edge. I tested many different openings in calm and wind conditions and found this to be the best based on shortest time to produce a boil.
Now you need a way to hold this in its circle shape as it wants to spring flat. To make this easier you need to remove the temper in the metal itself. Use some old wire (with no insulation) and make a circle with a 4 ½ inch diameter, twist the ends so it holds shape and slide it over your rolled windscreen. Place this in your oven in your home and heat to 400 degrees F. for 45 minutes and then turn off the oven and let it cool with the oven closed. When done it should keep its new curved shape fairly well.
To finish off the windscreen you need a way to hold it together to maintain the proper shape. The wire worked for the oven but needs to be improved upon for field use. I tried combinations of hardware and special slots and folds when I stumbled across a write up for the windscreen beltbuckle. This rather simple device solves the problem and weighs nearly nothing. Cut a strip of flashing about 9 inches long and ¾ inches wide. Slightly round the corners and lay it along the side of your circular windscreen from top to bottom where the windscreen overlaps. You should have about a ½ inch of overlap on top and bottom. Simply fold over the top and bottom to form a clamp and squeeze to pinch the windscreen and hold its shape. Holes can be punched in the buckle to reduce the weight if desired.
The first few times you use the windscreen it will give off a little smoke and smell funny as a coating on the flashing burns off so don’t be alarmed. It will also discolor a little and look burnt. This is normal.
The final item to manufacture is the pot cozy. This is the item that will help your pot retain heat once you have heated your water and keep you from burning your hand when you drink hot beverage from it. This is made from a material called Reflectix and is held together with aluminum tape or duct tape. The aluminum tape is more durable and looks more professional but duct tape can be used. For the background I have provided additional information here under Mods for your Mug, see Mod 3.
Fabrication of the cozy is explained fairly well under Mods for your Mug. You will need an 18” long piece of the 16” wide Reflectix product. Cut a 13” long piece of the aluminum tape and apply half of it to the thin, non bubble section along one edge as shown. Fold the non bubble section over and tape down. Measuring from the folded tape edge, come down 5 ¾” and cut out a piece that is 5 ¾” by 13”. You should now have a rectangular piece with the tape along one side. Fit this to your pot and trim as needed so that the edges just touch, there is no overlap and the pot can easily slide out. The pot will expand slightly with heat so a slightly looser fit is OK. Follow the same instructions to make a second one to go around the first but this time use a 14 1/2” strip of tape and cut a piece that is 14 1/2” by 5 ¾”. Complete the bottoms as shown in the link. Make sure you make the bottom on the end of your circular cozy that does not already have tape on it.
When complete, the smaller cozy will fit the pot and larger one can be either doubled up on the bottom cozy or used like a cover to slide over the top of the pot and smaller cozy to make an insulated chamber.
You now need a few little items to complete the whole package. You need a fuel bottle to store your fuel in. I use a flip top 4 oz. bottle from REI or Sport Chalet but any bottle with a flip top that will fit inside your pot will work. A silicone wrist band (like the Lance Armstrong yellow bands) is another item you need. This is used to place around the mouth of the pot to prevent you from burning your lip when drinking from it. You need a way to light this thing so either matches or a flint and steel (my preference) goes in the pot. Lastly, you need an eating utensil. A plastic spoon is OK but I have broken and melted a few so I now carry an aluminum spork.
That sums up the making of the ideal cook kit. I have provided instructions for the packing and use of your new stove system below. I hope you enjoy it and get as much use out of yours as I have mine. I have had my Cub Scout Webelos Den make these and the kids were very excited. You have never seen a child so excited to boil water! They also make great gifts for your backcountry friends.
I am considering offering the materials in a kit. Please contact me if you are interested.
Alcohol Stove Operating Instructions:
This stove is a complete cookset if used as described below. No additional pots, pans or other cooking items other than your preferred eating utensil are required ( I use an aluminum spork).
Use denatured alcohol from the hardware store. There are other alcohol based fuels out there and you can read up on those but denatured alcohol is the most consistent from my tests. NEVER USE WHITE GAS OR GASOLINE!!!
Remove all items from the complete stove set. Set the stove (the small catfood can with the two rows of holes) on a non flammable flat surface. You may want to carry a piece of aluminum foil to place under the stove to protect the ground but that is optional. Next you need to get the windscreen ready so open it up to form a 4 ½ circle. You should just have about ¾ inch of overlap when formed correctly. Use the long metal strip to pinch the windscreen at the overlap to maintain the correct shape. Add an appropriate amount of water to heat in the Heineken pot and place lid on pot.
Getting it started:
Add alcohol to the stove. The appropriate amount depends on many factors including water temp, air temp, wind, quantity of water and desired finish temp. When boiling 2 cups of water in cool weather I would add fuel right up to the lower set of holes in the stove. You may be able to use less but this is a good start point and will let you see how long your stove will run for. If only boiling a cup of water with no wind you may be able to get away with half as much fuel or even less. You will need to experiment to work this out as each stove is a little different.
With the fuel added, light it and observe. The flame is nearly invisible during the day so use your hand to determine if it is lit by feeling above the stove for heat. You need to let the stove burn until you start to see little bubbles in the alcohol forming near the edges of the stove. This priming phase takes less than 30 seconds typically but may take longer in cold conditions.
Add your pot with water and lid on it to the top of the stove and make sure the silicone lip guard is removed. I would suggest wearing a glove when doing this as some flame does come up the side of the pot as you place it on the stove. With the pot in place slide the windscreen over the pot to protect everything. Make sure the row of holes around the windscreen is at the bottom. Sit back and wait for steam to come out around the lid. If you are going to heat a foil packet of meat or a can of chicken you can place it directly on top of the lid for the stove unopened. It will get warm but not too hot to damage the packaging.
As this stove is very hot while running, it is suggested you let it burn out before removing your windscreen and pot. Remove the windscreen when the stove has run out of fuel and remove the pot and place in the smaller cozy (the metalized bubble wrap) that snuggly fits the pot preferably with a glove on. Once in the cozy, you no longer need a glove as the pot will be well insulated. If you are making a hot beverage, mix it directly in the pot and place the silicone wrist band around the lip of the pot to make a lip guard so you do not burn your lip on the metal pot while drinking. To keep the fluid warm for a longer period of time, add the larger cozy over the top to seal the pot inside.
When finished and it is time to pack it up, make sure the pot is dry. You will first roll up your windscreen and slide it into the pot. Next you need to put the stove into the pot, open end up, and slide it to the bottom of the pot with the windscreen touching the outside of the stove as you slide it down into the pot. Then place your fuel bottle, matches, spork and silicone wrist band into the pot. Place the lid for your pot on top of the windscreen that extends out of the pot. Place the pot lid on the top of the windscreen extending from the pot with the lip of the lid facing down to cover the top edge of the windscreen. Place the smaller cozy over the bottom of the pot and the larger one on the top covering the windscreen and you are all set.
My typical use of this setup includes boiling water, pouring some into a freezer bag meal I have created (adding a can of chicken I heated on top of the pot) and sealing it and placing in the bottom of the large cozy. I will then place the pot with small cozy on top of my meal to trap it between the two. I will them make a hot beverage in the pot while I am waiting on the meal to rehydrate and warm. I will add the lip guard and drink with the whole setup in my hand. Check out freezer bag cooking or FBC as this method is particularly well suited to this type of stove.
I do not claim to be the inventor of any of this stuff, I just came up with a slick way of incorporating several peoples different ideas into one handy setup. If you like it, share it with a friend. For instructions on building one of these please see my blog at http://hikingandscouting.blogspot.com