build a low tech cfv stove - super water absorbent material
The most popular alcohol-based DIY backpacks and camping furnaces use aluminum beverage cans to provide flames for the supply of air or pressurized steam.
However, their fuel storage and thermal capacity, durability and adaptability are limited.
Most require an unrelated pan holder or holder and have additional requirements for structure, storage, start-up and use.
And high-tech CFV (
Capillary force vaporizer)
Burners represent advances in technology and unfortunately they are too high-tech to be available as a solution to DIY stove manufacturers.
Fortunately, the low-tech CFV furnace can overcome the limitations and shortcomings of the high-tech CFV furnace and alcohol fuel beverage tank furnace, the method is to use a low temperature evaporation alcohol fuel made of almost any absorbent material to surround the perimeter of the pad Wick.
In fact, it may (
Except for the flame)
It is correctly called the capillary force evaporator furnace.
Although it is simple in structure and easy to use, it can meet almost any fuel storage, and the thermal power generation capacity or durability requirements have become past except for the trouble of replenishing fuel during operation and starting.
A basic low-tech diy cfv stove can be manufactured quickly in case of emergency to meet most fuel or heat needs, but it can be adjusted and manufactured as time and material increases, camping or other needs.
You need some aluminum plates.
This can come from any source to meet any of your requirements for durability.
To build the test furnace, I used aluminum flash because it was about the minimum thickness fixed with 1/8 "rivets.
Aluminum or stainless steel rivets can be replaced with brass, stainless steel or aluminum machine screws.
Since I would most likely not take the stove apart, I used aluminum rivets.
Aluminum rivets are easiest to remove if I do need to take apart.
If you go with a pop rivet, you need a pop riveting gun, and a 1/8 "1/8" pop rivet, plus the thickness of the stove you want to build --
Usually 1/4 long rivets will provide enough space for the fuel.
Be careful not to over compress them like I do.
Next you need some aluminum door screen.
The size and number of pieces of aluminum plate and aluminum mesh are the same.
Your size will be large enough to be 1/16 to 1/8 larger than the pot you plan to boil water.
For a frying pan, the size you want is half the diameter of the frying pan.
I cut the screen and the sheets with a kitchen cutter.
You will need a straight edge, ruler, paddle compass, power drill bit and 1/8 drill bit as well as some absorbing material.
I use normal kitchen paper towels, but cotton or glass cloth will definitely be more durable.
In addition to synthetic materials and melted plastic, the choice of absorbing materials is yours.
Update: I have now tried fiberglass horn hair, mat and stone cotton and I am not very satisfied either.
The hair is very easy to absorb, so you can't add fuel until the pot is placed on the stove, otherwise half will overflow.
The fiber of the mat is too straight and hard to loosen and break into pieces.
I tried to seal them on the edges and sides with a flashlight, but the glass broke again and exposed the fibers.
The stone cloth is the best, so I think the glass cloth can be at least as well.
I only recommend alcohol fuel because oil, mineral spirits and kerosene need to be heated in closed containers until they are pressurized, otherwise they will burn incomplete and produce excessive carbon monoxide and soot
Cut diameter you want the diameter or circumference of your stove to be a little larger than the pot you will be using.
You don't have to be round in your pot.
If you want, you can use a square tea can and just make the stove a little bit bigger so that your tea can be placed on the stove with the smallest bumps of the stove, the maximum frustration is 1/8 "the pot gives no more than 1/8" clearance from the edge of the furnace.
The first stove I built was a 12 oz and 24 oz soda tank.
I used the external size of the bottom foot because there is a cone from the tank foot to the side to let the flame follow.
Because these dimensions are 2-3/16" and 2-
1/2 "I added 1/8" with a cutting diameter of 2-
5/16 of 12 oz cans and 2 oz cans"
5/8 of 24 ounces ". can.
For this note, I decided to build a stove that was able to boil 1 liter of water in a bean jar of 404x700 and boil 2 liters of water in a coffee can of 602x602, I chose diameter 4 to meet the specifications-
The 1/4 "plus 1/8" uses only flat or coffee cans to support the bean cans and the bean cans to support the coffee cans.
The thickness or height uses a little bit of math and chemistry to help guide me in choosing the thickness or height, but once you have calculated the basic requirements, you can fine-tune it with track and error.
Cook 2 or 4 liters
From 60 degrees Fahrenheit to 41 lbs of water, I need to add 15f to raise the temperature to 212F.
I BTU need to increase the temperature of 1 pound of water, 1 degree.
So I need four.
670 or pound. 2 BTU.
91% acetone contains 20.
73 BTU/g so I need 32.
Boil 2 liters of water from 60F and add 33 grams of promethyl fuel.
Because life will give it heat and evaporation loss, it takes 50 to 60 grams of fuel to cook 2 liters of water in actual operation.
If I use a container to store the stove to keep any unused fuel, then I can make the stove thick enough to hold the excess fuel.
However, this is a trend even if the weight of the pot increases the burning speed, so I'm testing another method, that is, using the top of the bottom lid as a small fuel stove can be tapped through a rope through the center of the burner.
This helps in practice, but if the reservoir fuel becomes hot enough to escape under pressure, then if will further increase the burning speed and start to produce a yellow flame.
Although the efficiency is a bit low, the water is boiling.
Since isopropyl weight 0.
785g per cubic centimeter, I need to make at least 4 spaces.
Cook 2 liters of water with 66 cubic inches of heterogeneous fuel.
For a furnace with a diameter of 4.
375 I need a height of 0.
The thickness or height is 31 "or 3/8 ".
Since the efficiency of the paper towel is only about 40%, I used a rope to feed the burner from the reservoir at the top of the bottom of the bean jar for 2 liters of boiling.
So I need a stack of compressed paper towels 3/8 thick 4-
3/8 in diameter ".
Next, I copied a 4-with a layout compass-
3/8 "the upper and lower parts of the furnace are round in diameter made of two aluminum plates, then cut out the disk and drill a 1/8" and then, in the center hole, I put two uncut screens on each end of the cut paper towel, and then put two aluminum plates on the screen in a two-piece bread sandwich.
Next, I use drywall screws to temporarily fix the assembly together by passing the assembly through the center of the Assembly when it is compressed.
Then, I drilled three holes with 1/8 spacing from each other, about 1 inch from the center, and installed pop rivets through them to fix the Assembly permanently together.
Finally, I trim the screen to match the diameter of the aluminum disc and paper towel, remove the drywall screws from the center hole and insert a 1 inch rope in its position.
The 2-liter boyilan empty bean jar is upside down and is filled with the same amount of propos around the middle of the ridge.
If you want a larger reservoir, then you can use a rubber mallet to punch the end of the can into a deeper depression than the one provided only with the bean can Ridge.
After the first stove had only 20 grams of fuel on it, I filled the reservoir with 40 grams of fuel.
Now, the stove is either soaked in a plate full of 91% acetone, or if you find a leak-proof container for the stove, the container is filled with acetone, and the stove is also soaked in it.
Next, the stove is placed at the top of the bean jar so that the rope can absorb the fuel while burning.
Next, the coffee can is filled with 2 liters of water and dry completely outside.
Not drying outside can pollute the fuel.
Next, the coffee can is centered around the top of the stove.
The bottom of the coffee can will extend to the stove, and the Bean can is about inches.
1 liter boiled coffee can is poured over, the stove is filled with fuel, centered on the top of the coffee can and bean can, filled with 1 liter of water, centered on the top of the stove.