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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
- Make a nail collection. How many different kinds can you find?
- Try to identify the different purposes of each of the above
nails.
Try filing each nail. Are they harder or softer than the file?
Some are harder than others.
File or grind a galvanized nail in one place, exposing the metal
underneath. Leave the nail in a warm, damp place with a galvanized
nail that hasn’t been filed. Does rust appear where the galvanize
was removed?
It should. The galvanize is just a coating.
- Find a building in town where the siding was nailed on with
nails that weren’t galvanized. Can you see the rust “bleeding”
through the paint or down the side of the building?
There should be many examples of nail heads rusting and “bleeding”
down the side of a building.
- Experiment with different nails: long, short, smooth and rough.
Can you determine why they are different? Drive each one into
a board with the head slightly above the surface of the board.
Pull them one by one. Do the ring nails or galvanized pull out
easier or harder? Can you tell the difference?
Ring nails should be a little harder than the galvanized,
but the both of them are harder than smooth or sinker nails.
- Draw a nail that would hold two inches of foam to a wood surface?
Imagine in your mind what would happen when the head of the nail
pressed against the surface of the foam. How would you design
a nail for this purpose?
It would need a very large head, perhaps two inches in diameter.
- Drive nails into the end grain of a board. Do they hold as
well, better or worse than cross grain?
They don’t hold as well in the end grain as they do cross
grain.
- Look at the point of a spike (end view). Can you see how one
side is tapered more than the other? Draw what you see.
- Try the tricks mentioned in this chapter to prevent splitting
at the end of a board. Do they help to keep the wood from splitting?
Use green frozen lumber.
They should.
- Listen to a good carpenter drive nails on a surface like a
floor or roof. How is his nailing different from that of an inexperienced
person (apart from speed)?
A good carpenter nails with rhythm. An inexperienced carpenter
bangs away irratically.
- Research how nails are now made. Find a case of nails. Where
were they made? How were nails made before modern machinery?
- How much does a pound of nails cost in the village? How much
does this come out to for each 6d, 8d, and 16d nail?
- Pull some old nails from a board. Does driving them first to
loosen them seem to help?
It defies reason to drive a nail in so you can pull it out,
but the techinque works. Breaking the nail loose from the place
it has been for a long time allows it to come out much easier.
- If there is a nailgun in the village, have an experienced person
demonstrate. Can ten students drive ten nails as fast as one person
with a nail gun? What are the safety features of a nailgun so
someone can’t be shot with a nail? What are some of the hazards
of nailguns? What can you learn about the pressure of the compressor,
specifically the difference between a framing gun and a finish
gun?
A nail gun can easily out-nail ten students. A framing gun
operates over 90 lbs./squarre inch of pressure. A finishing gun
operates around 60. Finish nails are smaller, and require less
force.
- Ask a good carpenter about hammers. What weight hammers are
used for different applications? Waffle and smooth faces? What
are the differences between steel, wood, and fiberglass handles?
Why do people prefer one over another? Which hammers are better
in different situations? Why do you think there is such a variety
of hammers?
Most framers use a 20-24 oz hammer with a rough waffle face
to grip the nails and drive them quickly. A finish hammer is usually
16 oz, and has a smooth face. A sheet-rock hammer is waffle-faced
to create a rough surface for the sheet-rock mud to adhere to.
- Ask an oldtimer in the village to demonstrate lashing a fishtrap.
What lashing material was commonly used? Videotape if possible.
Spruce roots were used.
- Ask a local sled builder to demonstrate how to lash a sled—crosspieces
and stanchion—to the runner. Videotape to show others.
- If there is a log cabin in the village, inspect the corners
and inspect the pins used. Are they spikes or wooden pins? What
kind of wood was used for pins? Ask a local person where the pins
were placed in the wall and why. If spikes were used, ask them
how the holes were drilled to allow for settling of the logs.
Student Response
- What will happen if a nail is too short? Too thick? Too smooth?
Too thin?
Too short: it will pull out. Too thick: it will split the
wood. Too smooth: it will also pull out. Too thin: it will bend
going in or break under stress
- Draw the type of nail that is used on tar paper and roofing
shingles.
Big head.
- What kind of nail would you use on a boat?
Ring nails. They have such high friction they hold well when
the boat is working in rough water
- Draw the end view of a nail. Show how it should be driven if
it is close to the end of a board.
- Draw a nail that would have high friction in wood. Draw one
that would have low friction.
- Draw a scaffold nail.
- Why are galvanized nails used?
They don’t rust. An ungalvanized nail will rust and bleed
through paint and stain. Galvanized nails also hold well because
they have rough surfaces.
- What is the name given to describe the sizes of nails?
Penny symbol “d”
- Why were pegs used in log cabins?
To keep the logs in line above one another, particularly around
the windows and doors.
- Why are spruce roots superior to all other materials for a
fishtrap?
They don’t stretch, are easily cleaned, don’t rot
easily and are available to anyone with ambition in country that
has spruce trees.
- What is the best lashing for a sled and why?
Braided halibut twine. It doesn’t stretch and it wears
well. Rawhide stretches when it is wet and dogs like to eat it.
Math
- If a 50 lb case of 8d galvanized nails cost $57, what is the
cost of 27 lbs at the same rate? 150 lbs?
$30.78. $171
- Matt wants to use spikes on his cabin rather than wooden pegs.
Spikes are $.50 each. He figures that each log will average 3
spikes. There are 56 logs in the house. How much would wooden
pegs save him?
$84
- If Matt’s time is worth $10 an hour and he can make 12
pegs an hour, which is cheaper?
14 hours = $140. Spikes are cheaper, but he might want to use
wooden pegs for other reasons
- Which is stronger: 4 larger nails with a shear strength of
65 lbs each, or 9 smaller nails with a shear strength of 52 lbs
each?
9 smaller nails.
- Two carpenters frame a whole house. The total time of both
workers is 80 hours using a nail gun (40 hours each.) They both
make $18 per hour. Without a nail gun, they will take 98 hours.
The special nails for the nailguns cost $100 more than regular
nails. Nailgun rental is $20 per day for 5 days. Are they saving
money?
$1440 wages, plus $200 for nails and gun rental totals $3080.
$1764 if they don’t use the nailgun.
- A 50 lb case of 16d galvanized nails costs $57 delivered to
the jobsite. A case of 16d sinker nails cost $42 delivered, but
Al figures that he has to use 20% more nails if he uses sinkers
because they don’t hold as well. Which is cheaper: sinkers
or galvanized?
The sinkers will cost $50.40 which is cheaper. What we didn’t
consider however is the added time to drive them.
- Sinker nails are $1 a pound delivered to the jobsite. Scaffold
nails are $1.50 delivered. Building scaffolding takes 30 lbs of
nails. Scaffold nails save 3 man-hours working at $12 per hour.
Are scaffold nails worth purchasing and using?
Sinker nails are $30. Scaffold nails are $45, but they save
$36 in man hours, so they are cheaper.
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