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Teacher
Edition Contents
Skill,
Tools, & Craftsmanship
Cutting
& Drying Fish
Sharpening
Nails,
Pegs, & Lashings
Falling
Trees &
Small-Scale
Logging
Guns
Chainsaw
Clutch & Chain
Ice
Pick
Shelters
Wood
Stoves
Wall
Tents
Steambaths
Insulation
& Vapor Barriers
Gas
Lamps & Gas Stoves
Travel
Piloting
A Boat
Boat
Design
Magnetos
& Spark Plugs
Carburetors
Compression
Outboard
Motor Lower Unit
Outboard
Motor Cooling System
Dogsleds
Snowmachine
Tracks
Snowmachine
Clutch
Snowshoes
Winter
Trails
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Activities
- To demonstrate that water is a byproduct of combustion, hold
a very cold piece of metal over a small flame. Can you get the
water in the smoke to condense on the plate?
It should.
- Hold your hand a safe distance over a candle flame. Can you
feel the warm air rising. Can you devise a way to demonstrate
this to others, like a pinwheel? (My last pinwheel burst into
flames.)
A strip of tissue held above the flame will flutter indicating
the hot air rising.
- Look at the wood stoves in your village. (Does everyone burn
oil? Check the steambaths.) Note the controls for air intake.
How many different kinds are there? Are most of the doors airtight?
What kind of dampers do the stoves have? Do all the stoves have
either mud or bricks inside?
A steambath stove doesn’t need an airtight door.
- Find a wood stove with a bimetal helix coil. Heat it with a
blow drier or other safe heat source. Watch it close. Cool it
with a fan or cold water. Watch it open. Gently file both sides
of the coil. Which is harder? Can you guess what kind of metals
are used?
One side is harder than the other. I haven’t a clue what
different types of metal are used.
- Put a very green stick of wood on a burning fire (a block from
the top of the tree will illustrate well). After ten to fifteen
minutes, open the stove door and observe the steam coming from
the wood. Can you hear it hiss?
It should be obvious.
- Get an old stovepipe that has been used on a wood stove. Scrape
the inside. What does the material smell like? Put the material
you have scraped on a metal plate and heat it. What happens. Try
to burn the material. Does it burn? Was the stove losing heat
by not completely burning the wood?
The condensation on the inside of the stovepipe should at
least glow when heat is applied. The stove lost the heat that
could have been released by the burning of the gasses that went
up the stovepipe.
- Make a campfire. Fan the flame. Does this increase burning?
If so, why? Put more wood on the fire. Does the fire burn stronger?
Why? Pour water on the fire. What happens and why?
Fanning a campfire increases burning because it is providing
more oxygen. If you fan too much it slows the fire by cooling
it off. More wood will temporarily slow the fire by cooling, but
will soon add to the fire as more fuel is being consumed. Water
slows the fire for two reasons. It cools the fire, and the resulting
steam blocks oxygen from getting to the fire.
- Put a candle in a jar. Light it. Put a metal cover on the jar.
What happens and why?
It eventually goes out when all the available oxgen is consumed.
- Discuss the difference between the convenience of burning green
wood versus the efficiency of burning dry wood. Ask the oldtimers
in the village about the advantages of each.
Greenwood is more plentiful, but it is heavy to haul. Drywood
is harder to find, but is lighter and more efficient.
- Send for information on modern commercial wood stoves. Discuss
the advantages of the different features.
Talk to some of the oldtimers in your village about stoves
they used to use for travel, for cabins, and homes. Is the information
consistent in your area with what I have presented here? If there
are differences, why do you think they exist?
Student Response
- What things go together to make wood?
Carbon, heat, and water
- When your house or tent is heated by a wood fire, where did
the energy originally come from?
The sun
- What three things does it take to make a fire?
Heat, fuel, oxygen
- What happens if a fire doesn’t get enough air?
It goes out or slows down
- With a given amount of air, how can you cause wood to burn
faster?
Increase the heat around the fire
- What does mud in the bottom of the stove do, or firebricks
in the modern stoves?
It holds the heat in the stove and keeps the rate of burning
more constant.
- Comment about the size of a stove, surface, size of stovepipe,
and air intake.
If the stove is too big, the fire will be too far from the
surface of the stove to conduct heat. If the stove is too small,
it can’t hold enough wood to burn long. Small stoves require
splitting wood very small.
If the top of the stove isn’t flat, it will be difficult
to heat water or cook on it. If the top is too high, it will take
a long time to heat water. If it is too low, the stove cannot
hold enough wood. Black stoves radiate more heat. If the stovepipe
is too big, all the heat will go up the stovepipe. If it is too
small, the fire cannot get enough air. If it is too short, it
cannot get enough draft.
- In an oil stove we control the flow of fuel. In a wood stove
we control the flow of what?
Air
- What are the disadvantages of burning green wood?
Heat is used to boil the water out of the wood. Additionally,
the steam interferes with the oxygen uniting with the wood.
Math
- How many cubic feet in a cord of wood? (4’ x 4’ x
8’)
128 cu. ft.
- How many cords in a pile 8’ x 5’ x 13’?
4.06 or 4 cords
- If green wood has 2/3 the available heat as dry wood, and dry
wood is $125 a cord, what is the fair price for green wood if
the same value is to be obtained?
$83.25
- What is the area of four tovepipes, 4”, 5”, 6”
and 8”. Is the area of the 4” pipe 2/3 the area of the
6” pipe? (When pi is 3.14)
12.56, 19.62, 28.26, 50.24. No, it is less than 1/2
- Look at a block of wood. Measure the diameter from the ages
of fifteen and sixteen years. Be kind to yourself; use metric
measurement. If the block were a perfect circle, what is the area
for each year? How much did it increase in one year? Do the same
operation between thirty-three and thirty-four years. How much
did it increase? How much greater or less was the growth in area
of the tree when it was younger than when it was older? Figure
the difference in volume if the block is .5 meters long.
The answer will be determined by the block of wood chosen.
A ring .25” in a young tree adds less volume to the tree
than a ring .25” in an older, larger tree.
- Compute the volume of the inside of three stoves. Compute the
area of the stovepipe of each stove. Is there a relationship (bigger
stoves have bigger pipes)?
The answer will be determined by the three stoves selected.
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