[Illustration: “Grizzly Giant,” a Big Tree in Mariposa Grove, California]
ELEMENTARY WOODWORKING
BY
EDWIN W. FOSTER
GINN & COMPANY
BOSTON · NEW YORK · CHICAGO · LONDON
COPYRIGHT, 1903
BY EDWIN W. FOSTER
ALL RIGHTS RESERVED
25.1
The Athenæum Press
GINN & COMPANY · CAMBRIDGE
· MASSACHUSETTS
PREFACE
This text has been prepared for the purpose of furnishing the pupil with
the essential facts about tools and their uses. However efficient the
instruction may be and however attentive the pupil, it is impossible for
him to fully grasp and comprehend during a demonstration the names of
tools and technical terms, most of which are new to him. This applies
with equal force to the manner of using the tools and to the methods of
working.
The function of the text is to supplement the instruction of the teacher.
It is intended to gather up and arrange in a logical order the facts
which the pupil has already been told. By this means these facts will
become fixed in the mind of the pupil and he will work with a better
understanding and make greater progress.
It is believed that the text can be used to the greatest advantage
by requiring the pupil to read up the subjects presented in class
immediately _after_ the close of the lesson. Frequent rapid reviews and
occasional written tests are very effective.
No course of study in the form of a series of models is presented. It is
hardly possible for any two schools to follow the same series of models.
Local conditions necessarily affect the choice of a course, while new and
better designs are being brought out continuously.
The order in which the tools are described in the following pages is the
one that has seemed most natural. They may be taken up, however, in any
convenient and logical order.
It is with the earnest hope that nature study and manual work may be
closely correlated, that Part II is added. No better period can be
selected in which to study trees, their leaves, bark, wood, etc., than
when the student is working with wood, learning by experience its grain,
hardness, color, and value in the arts.
Occasional talks on the broader topics of forestry, its economic aspects,
climatic effects, influence on rainfall, the flow of rivers, floods,
droughts, etc., will be found interesting as well as instructive, and
such interest should be instilled into every American boy and girl.
The writer is indebted to the Fish, Forest, and Game Commission of New
York state for the series of Adirondack lumbering scenes, and to the
United States Bureau of Forestry for the views of California Big Trees.
EDWIN W. FOSTER.
CONTENTS
PAGE
PART I. TOOLS
Chapter I. Introduction 3
General directions regarding care of tools and bench. Plan of
work and division of tools into groups.
Chapter II. Measuring and Marking Tools 5
The rule: divisions; method of using. The try-square: method
of handling. The framing square. The marking gauge. The bevel.
Chapter III. Cutting Tools 11
Saws: necessity for two classes; shape of teeth; set; tapers;
method of holding. Backsaw; use of bench hook. The turning
saw. The plane: use of cap iron; names of parts. Adjustment
of plane. Use of lever and adjusting screw; positions for
planing. The jack plane. The smooth plane. Jointers; action
of short and long planes. The block plane. The wooden plane.
The chisel: size of cutting angle; effect of careless
sharpening. The framing and firmer chisels; proper positions
for horizontal and vertical cutting. Sharpening on oilstone.
Brace and bit. Center and auger bits; gimlet and countersink
bits. The spokeshave.
Chapter IV. Miscellaneous Tools and Methods of Work 31
The hammer; use of nail punch. The mallet. The screw-driver.
Sandpaper, use of. Squaring up stock; method explained in
detail. Laying out work; method of laying out a typical
joint. Securing parts; use of glue and hand screws. Nails;
method of using cut nails. Screws; method of using round-head
and flat-head screws. Mechanical drawing. The drawing
instruments explained, and method of making complete working
drawings described. Scale drawings.
PART II. WOOD
Chapter V. Lumbering and Milling 51
The forest; felling trees and floating logs to the mill. The
forming and breaking up of log jams. The log boom and modern
sawmills. Timber and lumber defined. Annual rings; medullary
rays; formation of grain. Characteristics and defects in
wood. Warping and shrinkage.
Chapter VI. Broad-Leaved Trees: the Oaks 65
White oak. Post oak. Mossy-cup oak. Black and black-jack oak.
Red oak. Scarlet and pin oaks. Chestnut oak. Live oak.
Chapter VII. Broad-Leaved Trees: the Maples 76
Sugar and Norway maples. Silver and red maples. Sycamore
maple. Moosewood. Maple keys. Ash-leaved maple. Japan maples.
Chapter VIII. Broad-Leaved Trees having Compound Leaves 85
Horse-chestnut. Buckeye. The hickories. Black walnut and
butternut. Locust. Honey locust. Ash.
Chapter IX. Broad-Leaved Trees having Simple Leaves 94
Elm. The birches. Beech. Iron wood. Buttonball. Sweet gum.
Tulip. Basswood. Willow. The poplars. Sassafras. Mulberry.
Chapter X. The Evergreens 111
White pine. Georgia pine. Yellow pine. Hemlock. Spruce.
Cypress. Balsam fir. The cedars.
Chapter XI. The Big Trees of California 123
ELEMENTARY WOODWORKING
PART I
CHAPTER I
INTRODUCTION
In order to obtain good results in the using of tools it is necessary to
know their construction, how to properly sharpen and adjust them, and the
correct method of handling them. It is also essential to know how to lay
out and work the material or stock. Carelessness or a lack of knowledge
is invariably followed by a failure. It is more important at first to
work carefully and accurately than rapidly.
“Tools are made to be used, not abused.” They must be kept _clean_ and
_sharp_ and should be used only for the purpose intended. Wipe them off
occasionally with an oily rag or waste to prevent them from rusting. Put
away all tools not in use and keep the top of the bench clean. Do not
mark it with a pencil or scratch it with a knife. Do not cut into it with
the chisel or allow other tools to mark or deface it. When using glue,
shellac, or similar materials, cover the top of the bench; or, better
still, do the work on a table provided for that purpose.
The plan of work in making all models is in general the same and is as
follows:
_First._ “Squaring up” the stock.
_Second._ “Laying out” the work.
_Third._ Cutting to the lines.
When the article is composed of two or more pieces a fourth step may be
added, namely, fitting and securing the parts.
The tools used may be divided into three groups, as follows:
_First._ Laying-out tools. These include the rule, try-square,
marking gauge, bevel, and knife.
_Second._ Cutting tools. In this group are the saw, plane,
chisel, spokeshave, bit, and knife.
_Third._ Miscellaneous tools, such as the hammer, mallet,
screw-driver, brace (or bitstock), and others not so common.
CHAPTER II
MEASURING AND MARKING TOOLS
=1. The Rule.= The standard unit of length is the yard, but the foot is
commonly used for all measurements in woodwork. If the rule be twelve
inches long it is known as a foot rule, and if twenty-four inches long
it is called a two-foot rule. The inches are subdivided into halves,
quarters, eighths, and in some cases sixteenths. Rules are usually of
boxwood or maple, with brass joints, and are commonly made to fold once
or twice.
[Illustration: FIG. 1. The Rule]
The rule is quite thick, and if laid flat upon the work to be measured
errors will usually follow. It should be stood on edge so that the pencil
or knife point may touch the divisions on it and the wood at the same
time. The proper position when laying out measurements is shown in the
sketch (Fig. 2). Consecutive measurements should be laid off without
moving the rule.
[Illustration: FIG. 2. Methods of using the Rule: _A_, incorrect; _B_,
correct]
=2. The Try-Square.= The try-square has two distinct uses: first, to
act as a guide for the pencil or knife point in laying out lines across
the grain at right angles to the edge, as shown in Fig. 4; second, for
testing or trying the adjoining sides to see if they are square with each
other.
[Illustration: FIG. 3. The Try-Square]
The try-square may be made entirely of iron or steel, but sometimes the
beam _A_ is of wood with a brass strip _C_ to protect it and to take the
wear. The blade _B_ is of steel and is divided, like a rule, into inches
and fractions of an inch. Try-squares are made in several sizes, the most
convenient for general use being six inches.
[Illustration: FIG. 4. Methods of using the Try-Square]
In using the try-square the beam should be held firmly against the face
or edge of the stock. When working near the end of the piece, if the beam
projects, reverse its position. For nice, accurate work the knife point
instead of the pencil should be used for lining.
When it is desired to saw off the end of the stock it is first necessary
to mark or square clear around it with the knife and try-square. In doing
this the beam of the try-square must be used against the work face and
joint edge only. Large squares made of steel in one piece are called
_framing squares_, and are used by carpenters and others for rough or
large work.
[Illustration: FIG. 5. The Framing Square]
[Illustration: FIG. 6. The Marking Gauge]
=3. The Marking Gauge.= The marking gauge is shown in Figs. 6 and 7. _A_
is the gauge stick, _B_ the gauge block, _S_ the set screw, and _P_ the
marking point, or _spur_. The gauge stick is graduated like a rule into
inches and fractions, beginning at the steel marking point; but as the
latter is not always exactly in the right place the graduations are not
entirely reliable. It is safer then to set the gauge with the rule in the
manner shown in Fig. 7.
Hold gauge bottom side up in left hand and rule in right. Place end of
rule against gauge block and the measurement desired at spur. Turn set
screw. The gauge is then accurately set. In the cut the gauge is set at
one inch and is ready for use.
[Illustration: FIG. 7. Setting the Marking Gauge]
To gauge a line parallel to the edge of a block hold the tool firmly,
with thumb and forefinger encircling gauge block. Tip the tool away from
you until the marking point (spur) barely touches the wood and push the
tool away from (never toward) you. The line made should be as fine as a
knife line. A little practice is needed to give the proper control, as
the marking point tends to follow the grain of the wood, which is usually
not straight.
[Illustration: FIG. 8. Holding the Marking Gauge]
A good plan is to use a small piece of prepared stock as a practice
block, laying out lines a quarter of an inch apart, then an eighth, and
finally a sixteenth.
=4. The Bevel.= The bevel differs from the try-square in having a movable
blade.
[Illustration: FIG. 9. The Bevel]
This tool may be used to lay out lines at any angle from zero to 180
degrees. The blade may be fixed firmly at any desired angle by simply
turning the set screw. The method of using it is similar to that of the
try-square.
CHAPTER III
CUTTING TOOLS
=5. Saws.= The saw might be described as a succession of chisels, one
back of the other. We can readily understand the action of the saw by
making cuts with a narrow chisel along the grain of a piece of wood, as
shown in Fig. 10 at _a_.
[Illustration: FIG. 10. Cutting with and across the Grain with a Narrow
Chisel]
The little pieces of wood removed in this way are similar to the sawdust
made by the saw, the only difference being that in the saw the teeth are
narrower and the little pieces consequently smaller, and instead of one
chisel dozens are being pushed forward at one time.
A saw with these chisel-shaped teeth, and used for cutting along the
grain, is called a _ripsaw_.
That this tool will not cut so readily across the grain may easily be
proved by again resorting to the narrow chisel and attempting to repeat
the first experiment. The wood will act as shown in Fig. 10 at _b_,
splitting along the grain in both directions. It is quite evident, then,
that a tool for cutting across the grain must be constructed in some
other way.
[Illustration: FIG. 11. The Saw]
Continuing this experiment, let us cut the fibers with a knife point in
two parallel lines across the grain, close together, as at _c_. It will
be found that the wood between these lines may now be easily removed with
the narrow chisel. This fact is made the basis on which we construct the
crosscut saw. Every tooth is sharpened to a point, one on the right side,
the next on the left, giving two parallel lines of sharp points designed
to cut the fibers, as was done in our experiment with the knife. Fig.
12 shows the end view of the crosscut teeth enlarged. Observe that not
only are the alternate teeth sharpened on opposite sides, but each tooth
is bent outward from the body of the saw. This bending is called _set_,
and is designed to make the saw cut, or _kerf_, wider than the thickness
of the saw, that the latter may pass easily through the wood after the
teeth have done their work. If it were not for this set, the fibers would
spring back against the body of the saw after the teeth had passed and
make the work very laborious. When a saw is properly set it should pass
through the wood easily.
[Illustration: FIG. 12. Teeth of Crosscut Saw]
[Illustration: FIG. 13. Teeth of Ripsaw]
The teeth of the ripsaw are also set, but, as will be seen in the sketch,
the bottoms are flat like a chisel instead of pointed like those of the
crosscut teeth.
Beside the end views of the two kinds of teeth, the side views, which are
also different, are shown in Figs. 12 and 13.
We are inclined to think of the saw as a very commonplace article, yet
a careful examination will prove that the greatest care and skill are
needed in its manufacture. Observe that the body, which must be of the
best steel, tapers, being considerably wider at the handle than at the
opposite end. This is to give strength, and to prevent _buckling_, or
bending, as the tool is pushed forward.
[Illustration: FIG. 14. Body of Saw, showing Tapers]
Most delicate measurements must be made, however, to discover that
not only the width but the thickness increases from _A_ to _B_, and
decreases from _C_ to _D_. How carefully this tapering must be done can
be realized when we know that the difference in thickness from _A_ to
_B_ is only three one-thousandths of an inch, and from _C_ to _D_ twelve
one-thousandths at end _A_ and five one-thousandths at end _B_.
[Illustration: FIG. 15. Method of holding the Saw]
The saw should be held in the right hand, with the left grasping the
board. The thumb of the left hand acts as guide, the saw is tilted, as
shown in Fig. 15, and drawn toward the worker at the first stroke. This
tool should be used without exerting much pressure, in accordance with
the general rule that we do our best work with tools when we work easily
and deliberately.
[Illustration: FIG. 16. The Backsaw]
Many varieties of saws are designed for special purposes, including those
which cut stone and metal.
[Illustration: FIG. 17. Method of using the Backsaw and Bench Hook]
=6. Backsaw.= The backsaw is a crosscut saw with small teeth, and has
a heavy steel backpiece, Fig. 17, to prevent bending. In this respect
it differs from the ordinary crosscut varieties, which bend readily.
The purpose of the backsaw is to make fine, straight cuts in delicate,
accurate work. The steel back _B_ is necessary on account of the thin
blade, but on account of the thickness of _B_ no cut can be made deeper
than the line _C_. This tool will cut in any direction with reference to
the grain, but is primarily a crosscut saw.
[Illustration: FIG. 18. The Bench Hook]
[Illustration: FIG. 19. The Turning Saw]
=7. The Turning Saw.= In ordinary work the saw is supposed to cut to
a straight line, but there are certain classes of work where it is
desirable to follow a curved line, and consequently a special tool is
necessary. The turning saw shown in the cut is used for this purpose.
The handles holding the saw blade may be turned in any direction with
reference to the frame.
=8. The Plane.= The plane reduces our rough lumber to planed, or
_dressed_, stock. The cutting part is a thin, wide chisel called the
_plane iron_.
[Illustration: FIG. 20. The Plane Iron in Action]
Fig. 20 shows the position of the plane iron in operation. Assume the
iron to be moving in the direction of the arrow on a piece of wood. The
sharp point would enter the board and, should the grain be unfavorable,
start a splitting action, as shown at _a_.
We wish to smooth the wood instead of roughing it, and must in some way
stop the splitting. This is accomplished by placing a cap iron on the
plane iron, as shown at _b_. The cap bends and breaks the shaving before
the splitting action has a chance to begin, and gives the spiral form so
familiar in wood shavings.
[Illustration: FIG. 21. Plane Iron, Cap, and Set Screw]
The cap is firmly fastened to the plane iron by a stout screw, and this
whole combination is fastened in the throat of the plane by a clamp
(Fig. 22). The opening on the bottom of the plane through which the
cutting edge protrudes is called the _mouth_ of the plane.
[Illustration: FIG. 22. Sectional Views of Iron Plane]
=9. Adjustment of Plane.= There are two ways of adjusting a modern iron
plane,—by means of the set screw _s_, and of the lever _l_.
Screw _s_ lowers or raises the plane iron so that we may take a thin or
thick shaving, and lever _l_ straightens the iron, which is liable to
project more on one side than on the other, and will then take a shaving
thicker on one side than on the other.
Before using the plane always examine it carefully. Invert the tool,
holding it toward the light with the toe toward you, and glance along the
bottom. If the iron projects, observe whether it is even, and if not,
move the lever until it is. For a thin shaving the cutting edge should
appear as a black line of uniform thickness. For a heavy shaving turn the
brass screw until the iron projects slightly.
In using the plane avoid a stooping position. Stand with the right side
to the bench and with the shoulders thrown back. Let the pressure of the
left hand be greater at the beginning and that of the right hand at the
end of the stroke. The tool should rest perfectly flat on the wood from
start to finish.
[Illustration: FIG. 23. Irons of Smooth and Jack Planes]
=10. The Jack Plane.= The ordinary plane iron has a straight edge, as
shown at _a_, Fig. 23, but when a large quantity of wood is to be removed
the iron is sharpened in the shape shown at _b_. This curved iron will
cut out the wood in hollows, leaving ridges between, and it is necessary
to follow this jack plane with a finer one having a straight edge in
order to smooth the surface. The jack plane might be called a _roughing_
plane.
[Illustration: FIG. 24. Relative Sizes of Smooth and Jack Planes
The lower figure is a jack plane]
=11. The Smooth Plane.= The smoothing plane is shorter than the jack
plane, its object being to smooth the surface without regard to
straightening it, as it is supposed that the straightening has previously
been done. The cap iron in the smooth plane should be set from a
sixteenth to a thirty-second of an inch from the cutting edge of the
plane iron.
[Illustration: FIG. 25. Action of Short and Long Planes]
=12. Jointers.= For straightening very rough and uneven stock a long
plane is necessary (Fig. 25). In the illustration let line _ab_ represent
the edge of a very uneven board. A short plane _c_ would simply follow
the hills and hollows, smoothing but not straightening it, while a long
plane, as shown at _d_, would merely cut off the top of the high places,
as shown by the dotted line, and would not touch the bottoms of the
hollows until all the elevations were leveled; in other words, until the
surface was straightened. Such planes, which are often three feet long or
more, are called _jointers_.
[Illustration: FIG. 26. The Block Plane]
=13. The Block Plane.= To square the end of a piece of stock the
conditions are quite different from those just described where we were
planing with the grain. In end planing no cap iron is necessary, the
plane iron in the block plane being reversed with bevel side up.
This tool requires more care than the others, as the stroke is usually
quite short, and if the cutting edge is allowed to reach the farther
corner, the latter will be broken off.
[Illustration: FIG. 27. Method of using Block Plane]
To avoid this error the plane must be lifted up before the end of the
stroke, as shown by the dotted line _a_. The piece is then reversed, and
planed as shown by arrow _b_. In this way the whole end is smoothed,
without ruining the corners.
Besides these standard planes there are many patent and special ones for
cutting tongues, grooves, beads, etc.
=14. The Wooden Plane.= Although the iron-bodied planes just described
are now in common use, the old-fashioned wooden plane is still the
favorite of many woodworkers.
[Illustration: FIG. 28. The Wooden Plane]
This tool, while lacking some of the adjustments of the iron plane, was
much simpler and contained a smaller number of parts.
The iron and cap were held in position by a wooden wedge, which was
driven in by a light blow of the hammer. The workman removed the iron and
wedge by turning the plane upside down and striking the forward part a
light downward blow on the bench, while the thickness of the shaving was
increased by a light tap on the plane iron.
One of the chief objections to the wooden plane was its liability to wear
and warp, so that it became necessary to straighten, or _joint_, the
face. No such difficulty is encountered in the iron-bodied plane.
=15. The Chisel.= The chisel is one of the simplest forms of cutting
tools. The size of the angle _a_ depends on the kind of material to be
cut.
[Illustration: FIG. 29. Cutting Angle of Chisel]
A chisel for cutting wood must be sharpened to an angle of from 30 to 35
degrees.
By careless sharpening an extra bevel is sometimes formed, as shown at
_b_.
The cutting angle is then no sharper than if the chisel were shaped like
that shown by dotted lines, and care must always be taken when sharpening
to keep the line _cd_ straight, so that angle _a_ will be the real
cutting angle.
Two classes of chisels are in common use: the _framing chisel_ used for
heavy work, such as the frames of buildings; and the _firmer chisel_.
The framing chisel is strong and heavy, and has a handle capable of
withstanding the blows of a mallet. The firmer chisel is designed for
finer and lighter work without the mallet.
[Illustration: FIG. 30. The Framing Chisel]
[Illustration: FIG. 31. The Firmer Chisel]
[Illustration: FIG. 32. Proper Position for Horizontal Chiseling]
The chisel must be sharp if we wish to do good and accurate work, and a
cut on the hand made by such a sharp tool is liable to be a deep one.
Special care must be used in handling it, keeping both hands away from
the cutting edge, as shown in the sketch, and placing it when not in use
where it cannot be pushed off the bench on to the floor or the student’s
feet.
Fig. 32 shows the method of using the tool on horizontal work, and Fig.
33 for vertical cutting. For this kind of work only a small portion of
the cutting edge can be used, the student judging for himself how heavy a
cut to take by the hardness of the wood and amount of strength required.
Good work can never be done when one has to exert all his strength on the
tool. The best results are obtained when we work easily.
[Illustration: FIG. 33. Proper Position for Vertical Chiseling]
Better work can usually be done with the chisel if, instead of pushing
it straight ahead or straight downward, we incline it somewhat so as to
secure a slight _paring_ action.
[Illustration: FIG. 34. Sharpening Chisel on Oilstone]
When the chisel becomes dull, unless its edge has been nicked or ruined
by some accident, it is only necessary to sharpen it on the oilstone.
Hold the tool with the bevel flat on the stone. A drop or two of oil may
be used to lubricate the stone, the tool being worked back and forth on
the face of it. Especial care must be taken to avoid a rocking motion,
which will produce a curved edge instead of a flat one.
[Illustration: FIG. 35. Common Forms of the Brace]
After the rubbing, reverse the chisel, lay the flat side firmly on the
stone, and draw toward you. This is to straighten the wire edge which
has been turned over by the rubbing. The wire edge may then be removed
by drawing the cutting edge across the end of a block of wood. When the
chisel is nicked or very dull it must be ground on the grindstone.
=16. Brace and Bit.= The old-fashioned augers and gimlets have given way
to the modern brace and bit.
[Illustration: FIG. 36. The Center Bit]
The brace, which is sometimes called the bitstock, allows both hands to
be used continuously, which was not true of the old-fashioned auger.
Several varieties of the brace are in use, the ones shown in the cuts
being common.
Bits are designed for a variety of purposes, the name being applied to
a tool which is to be turned by the brace. The old-fashioned center bit
shown in the cut possessed most of the essentials of a good boring tool.
[Illustration: FIG. 37. The Auger Bit]
The sharp spur in the center allowed the hole to be accurately placed.
The lip on the outer edge cut the fibers in a circle before the chisel
edge began to remove the wood, and so a smooth hole could be bored; but
considerable pressure was necessary to force the tool through the wood.
The progress that has been made in the manufacture of tools can be easily
appreciated by comparing this center bit with the modern auger bit.
Referring to the sketch (Fig. 38), _B_ _B_ are two knife points, or
_nibs_, which cut the wood fibers before the chisel edges, or _lips_, _C_
_C_, can touch the wood. The point _A_ allows us to accurately place the
center of the hole where we wish it, and the screw back of _A_ draws the
tool into the wood as it revolves. This part is known as the spur, or
_worm_. On this class of bits no pressure is necessary.
[Illustration: FIG. 38. Details of Auger Bit]
The opposite end of the bit, called the _shank_, fits into the brace. Any
tool with such a shank, and designed for use with the brace, is a bit. We
have screw-driver bits, gimlet bits, auger bits, etc.
On the shank of an auger bit will be found a number. This is the
numerator of a fraction whose denominator is 16. If we find this number
to be 4, it is a ⁴⁄₁₆, or a ¼-inch bit. If the number is 16, we have a
¹⁶⁄₁₆, or a one-inch bit, etc., always referring to the diameter of the
hole which the tool will bore.
In using the brace and bit care must be taken to see that the bit shank
is far enough in the brace to be fastened securely, and that the tool
is held at right angles to the wood. It may appear from the front to be
perfectly vertical, yet by stepping to one side and looking at it from
another position it will frequently be found far from vertical. When
starting a hole it is well to do this several times until assured that
the tool is working in a true upright position.
[Illustration: FIG. 39. The Gimlet Bit]
[Illustration: FIG. 40. The Countersink Bit]
The gimlet bit is used for small holes, such as we make for screws. In
this case the hole must be _countersunk_ to receive the screw head, when
flat-headed screws are used. The countersink bit is shown in the cut, and
its purpose is more fully explained in the chapter on screws.
=17. The Spokeshave.= The spokeshave is practically a short plane with
handles at the side so that the tool may be drawn or pushed. It may be
adjusted by means of screws to take light or heavy shavings, and is used
principally to smooth curved surfaces. The forming of a hammer handle
is a good illustration of the kind of work it will do. It may be worked
toward or away from the worker, and is an exceedingly handy tool.
[Illustration: FIG. 41. The Iron Spokeshave]
CHAPTER IV
MISCELLANEOUS TOOLS AND METHODS OF WORK
=18. Hammer.= The carpenter’s hammer is used principally to drive or
withdraw nails.
The various trades have hammers made specially for their needs; thus
we have machinists’, roofers’, upholsterers’, stonecutters’, and other
hammers, but the claw hammer shown in the sketch is the one commonly used
by workers in wood.
[Illustration: FIG. 42. The Claw Hammer]
The head _a_ (Fig. 43) is of steel, with the face _b_ specially hardened
so that it may not be dented by the nails. Notice the length of the
handle _h_. This length did not simply happen. Had it been intended to
hold the tool in the position shown at _A_, the handle would not have
been made so long. The proper position is that shown at _B_. Position _A_
is frequently taken by beginners, and should be studiously avoided.
[Illustration: FIG. 43. Using the Hammer]
A nail may be withdrawn with the claw, and be kept straight for further
use by a little care. Having started the nail slightly, place a small
block of wood under the hammer head, as shown at _C_. Should the nail be
an unusually long one, the size of the block may be increased as the nail
comes out.
[Illustration: FIG. 44. Common Forms of Nail Punch, or “Set”]
In driving nails care must always be taken not to mar the surface of
the wood by striking the nail head after it has become even with the
surface, as this produces a depression and ruins any fine surface.
If it is desirable to sink the nail head below the surface, a nail punch,
or _set_, is used. This is always necessary when the surface is to be
planed after the nailing.
=19. The Mallet.= The mallet might be described as a hammer with a wooden
head, and is used whenever we wish to deliver a blow which shall be less
concentrated than that of the hammer. It is used in certain kinds of
heavy chiseling, such as house framing, and gives a blow which does not
shatter the tool handle as a hammer would.
[Illustration: FIG. 45. The Mallet]
The use of the mallet is well illustrated by the making of a
mortise-and-tenon joint, the chisel and mallet being used to cut the
opening known as the mortise, as shown in Fig. 46.
=20. Screw-Driver.= The screw-driver is perhaps the most common of
household tools, and is probably abused more than any other. The handle
is usually flattened so that the hand may grip it more tightly, but
occasionally a round or fluted handle is seen.
Patent spiral screw-drivers have come into use in recent years, but where
considerable force is required the brace and screw-driver bit are more
effective.
[Illustration: FIG. 46. Cutting a Mortise]
=21. Sandpaper.= “Sandpaper is the last resort of a poor workman.” This
statement has been made by many teachers to many thousands of students,
and is true in many cases; but there are certain kinds of work where
sandpaper, if properly used, is allowable.
[Illustration: FIG. 47. The Screw-Driver]
It must always be kept in mind that a surface which has been sandpapered
has become “gritty,” i.e. the fine sand has come off and is more or less
imbedded in the wood. Consequently sandpapering must not be done until
all tool work has been finished, as the grit will take the edge off the
best tool, and the finer the edge the more quickly will it be ruined.
[Illustration: FIG. 48. An Exercise involving the Use of Sandpaper]
Again, a sandpapered surface is always a scratched surface, and the
finest of scratched surfaces cannot compare with the perfectly smooth,
satiny surface produced by a sharp plane. However, there are many places
where neither the plane nor spokeshave can be used, and here it is
allowable to use sandpaper after the tool work has been carried as far as
practicable.
Fig. 48 is a case where sandpaper may be used with propriety. The bevels
in this lesson are to be chiseled and then sandpapered with a sandpaper
block,—the block in this case being simply a small piece of wood with
square edges, about which the sandpaper is fastened closely.
Curved articles, such as the hammer handle, must dispense with the block,
the sandpaper being held in the hand.
=22. Squaring up Stock.= This term simply means to reduce a piece of
sawed or rough lumber to one having smooth, flat sides at right angles to
each other, and of definite length, breadth, and thickness (see Fig. 49).
[Illustration: FIG. 49. The Successive Steps in squaring up Stock]
_First._ Straighten one face with fore plane, jack plane, or
jointer, and smooth with smoothing plane. This face, called the
working face, becomes the basis from which all the other sides
are squared.
_Second._ Plane one of the adjoining edges and make square with
the working face. This edge, known as the joint edge, must
be thoroughly tested throughout its entire length with the
try-square, and must be square with the working face at every
point.
_Third._ Set marking gauge at required width and with gauge
block against the joint edge, gauge a fine line on working face.
_Fourth._ Plane down second edge to gauge line, just drawn,
squaring the edge with working face.
_Fifth._ Set gauge to required thickness and gauge line on both
edges from working face.
_Sixth._ Plane face parallel to working face down to the two
gauge lines. This gives the required thickness. It only remains
now to secure the required length.
_Seventh._ Square knife line around the four smoothed sides
with knife and try-square as near one end as possible,
carefully observing the precautions given in Chapter II.
_Eighth._ From the line just drawn, measure the required length
along edge of working face and square a line on the four sides
at the last point, as at first end.
_Ninth._ Block-plane first end to knife lines. If the second
line is more than an eighth of an inch from the end of block,
saw to the knife line with backsaw, and block-plane smooth and
square.
The above method should always be followed in preparing stock for laying
out the exercise.
=23. Laying Out.= Let it be assumed that the exercise to be executed is
the middle lap joint shown at _A_, Fig. 50.
[Illustration: FIG. 50. Successive Steps in laying out and making a
Middle Lap Joint]
_First._ Square up stock, leaving ends rough.
_Second._ Lay off the length of each piece, in this case 4½
inches, with an eighth of an inch between for sawing, as at _a_.
_Third._ Square all the lines around four sides.
_Fourth._ Saw to end lines and block-plane ends.
_Fifth._ Lay off width of opening in piece No. 1 and square
lines across face and halfway down on both edges.
_Sixth._ Measure length of lap on No. 2, square the line across
bottom and halfway up the sides. Gauge the horizontal lines
_ll_ from working face.
_Seventh._ Saw pieces No. 1 and No. 2 apart and block-plane
ends.
_Eighth._ Saw to the lines, chisel, and fit the pieces.
Although the above is the method of laying out a typical joint, each
problem will require special treatment and here the student will be
guided by his instructor.
=24. Securing Parts.= Many articles made of wood consist of several
pieces fastened together.
When two pieces are fitted together the surfaces of contact are called a
joint. There are many kinds and shapes in joinery, and usually some extra
fastening is required to hold the pieces together. These aids are glue,
nails, and screws; while on heavy construction still others, such as
wedges, pins, and dowels are used. The first three are commonly used in
small work.
[Illustration: FIG. 51. The Hand Screw]
Glue is of two kinds, fish and animal. Both are made from refuse
matter,—animal glue being manufactured from such products as bone, horn,
hoofs, and hide.
The dry glue in the form of chips must be dissolved in water and heated,
being applied while hot. Liquid glues sold in cans ready for use are now
very common and require no heating.
In making a glued joint it is usually necessary to hold the pieces
tightly together until the glue has _set_, or hardened, and as this takes
some time, hand screws built on the principle of the vise are resorted
to. Fig. 52 shows two pieces glued together and fastened in a pair of
hand screws. Care must always be taken to keep the jaws of the latter
parallel. At _a_ this is shown done properly, while at _b_ is shown a
careless method which, of course, will spoil the joint.
[Illustration: FIG. 52. Method of using the Hand Screw]
In gluing on the end grain a preliminary, or _sizing_, coat of glue must
first be made to fill up the pores, which act very much like a sponge.
This coat should be allowed to dry, or partially dry, before applying
the final coat; otherwise the pieces will be held weakly, if at all.
Beginners are inclined to use too large a quantity, and this tendency
should be avoided.
In some cases nails are used together with the glue, as at the corners
of picture frames. It is customary in this instance to nail in only one
direction, as shown in Fig. 53.
[Illustration: FIG. 53. Miter Joint at Corner of Picture Frame]
=25. Nails.= The nails in common use are of two kinds, _cut_ and _wire_.
Two views of a cut nail are shown in Fig. 54, _a_ being the side view and
_b_ the front view. Notice that in the front view the sides converge like
a wedge, while in the side view they are parallel.
[Illustration: FIG. 54. Use of Cut Nails]
Care must always be taken that the point does not enter the wood as shown
at _c_, as the wood will be split by the wedge action; _d_ shows the
proper method.
Steel wire nails are now in general use. They are made from wire and are
consequently round in section, with a comparatively sharp point. There
are two distinct kinds, named _flat head_ and _bung head_.
Flat-head wire nails, as the name implies, have thin, flat heads, which
prevent the nail from being driven beneath the surface.
Bung-head wire nails, or _brads_ as the smaller sizes are called, have
very small heads, which allow the nail to be sunk below the surface. This
is done by means of the nail punch, or _set_, and is necessary when the
surface is to be planed after the nailing.
=26. Screws.= Screws are much used, and allow the pieces to be readily
taken apart. They are divided into two classes, _flat head_ and _round
head_, and are of steel or brass. Steel screws are either _blued_ or
_bright_. Bright screws are polished and blued screws are produced by
treating the bright ones with heat or an acid.
[Illustration: FIG. 55. Methods of using Screws]
Fig. 55 shows a flat-head screw at _a_ and a round-head at _b_. Flat
heads are used for the more common work where it is desirable to have the
screw head flush (even) with the surface or below it, while round heads
are used where this is not necessary. In the latter case round heads are
used partly because they are more ornamental. Flat heads must always
be flush or below the surface, and in all but the softest woods it is
necessary not only to bore a hole for the screw, but also to countersink
it with a countersink bit in order that it may receive the head. Two
methods of fastening with flat-head screws are shown in Fig. 55.
Sketch _A_ shows the two pieces of wood in position, the hole bored in
upper piece (only) and countersunk; _B_ shows the screw in position. In
this case the screw head is visible. It is occasionally desirable to hide
the screw entirely. Sketch _C_ shows the hole prepared for the screw; _D_
shows the screw in position and a circular wooden plug driven in over it.
The plug is then leveled with the surface and the screw completely hidden.
[Illustration: FIG. 56. The Difference between Perspective and Mechanical
Drawing]
=27. Mechanical Drawing.= A mechanical, or working, drawing is quite
different from a pictorial drawing such as an artist produces. The
artist’s drawing represents objects as they appear, while the mechanical
drawing represents them as they really are. Things in nature do not
look as they are. For example, when we stand on a railroad track the
rails appear to converge until they seem to meet in the distance. We
know that this is not the case, that the rails are really everywhere
equally distant. The optical illusion of the rails meeting at the horizon
is called perspective. Mechanical, or constructive, drawing takes no
account of perspective. In Fig. 56 _a_ is the perspective representation
of a track, while _b_ shows a track by mechanical drawing.
In a working drawing more than one view is necessary to show the true
shape of an object.
In Fig. 57 is shown the mechanical drawing of a cylinder,—the front
view, as its name implies, being the image it would make in a mirror
held before it vertically, and the top view the image it would make in a
mirror held directly over it horizontally.
[Illustration: FIG. 57. Mechanical Drawing of a Cylinder]
[Illustration: FIG. 58. Mechanical Drawing of End Lap Joint]
Occasionally three views are necessary. Fig. 58 _a_ shows the front, top,
and side views of an end lap joint. The complete working drawing of this
joint, with all the necessary dimensions, is shown at _b_.
[Illustration: FIG. 59. Drawing Board showing T Square and Triangles in
Position]
In making drawings of this kind the greatest accuracy is required and
special instruments are necessary.
The drawing board on which the paper is fastened must be perfectly flat,
with one of its edges straight.
[Illustration: FIG. 60. The T Square]
The T square is used for guiding the pencil or pen when drawing
horizontal lines.
The two triangles _t_ _t_ (Fig. 59) are used for drawing vertical and
oblique lines, and a pair of compasses is needed for circles and arcs
of circles. Each triangle contains one right angle, the one on the
left being known as a thirty-sixty triangle because the two remaining
angles are thirty degrees and sixty degrees respectively. The one on
the right is called a forty-five-degree triangle because it has two
forty-five-degree angles.
The position of T square and triangle when drawing vertical lines is
that shown in the sketch, the line being drawn from the T square upward.
Horizontal lines are drawn from left to right.
The rule used in mechanical drawing is called a scale, and should not be
used for drawing lines. Its purpose is measuring.
[Illustration: FIG. 61. The Triangles used in Mechanical Drawing]
In making a drawing the first step is to determine the spacing. The size
of the paper may be measured, the number of views are known, and also the
size of each. The views should be so arranged that the spaces between
will be in good proportion. It is a good plan to make first a free-hand
sketch, putting on dimensions and figuring the spaces before beginning
actual work on the mechanical drawing. Fig. 62 at _a_ shows a free-hand
sketch of a single dovetail joint, and _b_ the mechanical drawing
complete.
[Illustration: FIG. 62. Drawings of a Single Dovetail Joint]
All dimensions must be given, and as far as possible they should be so
placed as not to interfere with the clearness of the drawing. Neat, small
arrowheads and plain, clear figures add to the general appearance, just
as does careful lettering in titles and all printed words.
A drawing which is made the exact size of the object represented is
known as a full-sized drawing; but for large objects such a method would
necessitate large and unhandy sheets of drawing paper. It is customary in
such cases to make what is called a scale drawing.
A scale drawing may be half, quarter, or eighth size, and the fact is
printed under the title in smaller letters, thus: ½ inch = 1 inch, or ¼
inch = 1 inch.
Other scales may be used. In map making, for example, a sixteenth of an
inch may represent one, ten, or even a hundred miles. Whatever scale is
used, however, the dimensions must always give the exact size of the
object represented.
ELEMENTARY WOODWORKING
PART II