making of Indian cots. The illustrations indicate how the cross bar and
end bar are mortised into the leg. A turned hardwood peg fits into a
suitably provided hole and locks the tenons, which are dry jointed (not
glued) in position. The head of this peg forms an ornament (A) at the
top of the leg and should fit tightly in position. At B are seen the end
and cross bars in their relative positions when apart from the leg. C
shows the end bar and cross bar when the cot is fixed, but in this
illustration the leg is purposely left out of the drawing for a clear
representation. D shows the joints of the leg portion when the part of
the leg above the line at A is sawn off. The hardwood peg is shown at E.
[Illustration: Fig. 347.--Fixing Muntin to Skirting.]
[Illustration: Fig. 348.--Joint for Home-made Cot.]
SIDEBOARD PILLARS, ETC. (Fig. 349).--For economy, sideboard pillars are
sometimes built up as indicated, the "shaft," the "base," and the "swell"
being made up of three distinct pieces. Turned pins are left on the shaft
and the base, and these are secured at the joint by the use of a
double-pointed screw called a dowel screw. This does away with the
necessity of reducing the squares at the top of the wood and thus getting
the turning out of a large piece of wood.
NOTCHED JOINTS.--Fig. 350 is a "notched joint," where two joists, or
scantlings, cross each other, the object of the joint being to prevent
the joists moving from their position without materially weakening them.
For an end notch, see Fig. 352.
[Illustration: Fig. 349.--Method of Building up Turnings.]
[Illustration: Fig. 350.--Notched Joint.]
[Illustration: Fig. 351.--The Saddle Joint.]
The "saddle joint" (Fig. 351) is used for connecting upright posts to
heads or sills of framing, and undoubtedly takes its name from its
similarity to the way in which the saddle fits the horse. It does not
weaken the framing as does a mortise and tenon joint, and shrinkage has
little effect upon the joint. The "cogged joint," used for connecting
purlins to rafter and joists to girders, is illustrated in Fig. 353.
[Illustration: Fig. 352.--End Notch.]
[Illustration: Fig. 353.--Cogged Joint.]
[Illustration: Fig. 354.--Birdsmouth Joint.]
[Illustration: Fig. 355.--Another type of Birdsmouth Joint.]
BIRDSMOUTH JOINTS.--Fig. 354 is a "birdsmouth joint," a simple joint
which can be readily made by the handsaw, used when a spar fits on the
wall plate. A nail is shown securing it in position.
Fig. 355 shows the birdsmouth joint where the spar runs over the
_outside_ of the wall plate, thus allowing a fixing for an ornamental
finish.
[Illustration: Fig. 356.--Rafter and Tie Beam Joint.]
RAFTER JOINT.--Fig. 356 shows an everyday joint, as used at the juncture
of the principal rafter and the tie-beam in roof truss work. A sketch of
piece A is shown separated, and it should be noted that the depth of the
cut portion B should not be more than one-fourth of the total width of
the tie-beam.
[Illustration: Fig. 357.--Method of Pelleting the Corner of a Mitred
Picture Frame.]
PELLETING.--Fig. 357 indicates the method of pelleting and screwing the
corner of a picture frame. The mitre joint is first screwed and a pellet
of the same timber is made to fill the hole which has been bored to
receive the screw head. The pellet is glued in position and levelled off.
[Illustration: Fig. 358.--Patera Covers to Hide Screws.]
PATERA COVERS.--In cases where the style of ornament permits of it,
patera covers are used instead of pelleting. Fig. 358 shows the jointing
of shaped spandrails, etc., to carcase ends of light portable cabinet
work, etc. A hole is bored about 3/8 in. deep into the end, and a screw
is used to hold the shaping in position. After fixing the rail a small
turned button, called a turned patera, is inserted in the hole, thus
giving an ornamental finish, as shown in the front view. The turned
patera is driven fairly tightly into the hole, but not glued. When it is
required to take the article apart a chisel is carefully inserted under
the edge of the patera to remove it, and the screw can then be taken out.
This method is often used for the construction of light hanging bookcases
and similar objects. For a bookcase having an end 8 ins. wide three of
these turned buttons and three screws would be used to secure the shelf
to the end. Pateras in different styles may be purchased from any dealer
in woodworking sundries.
BUTTONING.--The tops of tables, sideboards, etc., should not be fixed
with screws in the ordinary way. At the front, screws can be driven
upwards through the top rail, but at the sides and back, buttons should
be employed, as in Fig. 359, so that the top is free to shrink. It is
otherwise liable to split if immovably fixed. The tops of kitchen tables
are usually fixed in this way, to allow for shrinkage.
[Illustration: Fig. 359.--Method of Buttoning a Table Top.]
FRAMES FOR OIL PAINTINGS.--The method of making joints for frames on
which the canvas is stretched for oil paintings is shown at Fig. 360.
They are generally mitred at the corners and fitted with loose wedges.
The four parts of the frame can be held temporarily by a piece of thin
board while the canvas is being tacked to the edges of the frame. In the
accompanying illustrations Fig. 360 shows the action of the wedges when
tightening up the frame, the result being to open the mitre joint. Fig.
361 shows the position of the saw cuts for receiving the hardwood wedges.
Note that the parallel groove is carried the full length of the material
for greater convenience in cutting. The other groove is taken from the
outer angle of the mitre joint inwards. The cut finishes with due regard
to the necessary taper; see the dotted lines showing taper in Fig. 360.
The grooves will be wide enough after being cut with an ordinary hand-rip
saw, but for large work they are usually grooved on the circular saw
bench.
[Illustration: Fig. 360., Fig. 361. Joint and Method of Wedging
the Frames of Oil Paintings.]
CORRUGATED STEEL FASTENERS.--It is now many years ago since the steel
saw-edge fastener first appeared on the market, but probably 80 per cent.
of amateur woodworkers have never yet sampled its advantages.
In appearance it resembles a miniature corrugated galvanised sheet such
as is used for roofing purposes, with the exception, however, that the
corrugations are divergent instead of being parallel and that one end is
ground down to a cutting edge (see Fig. 363, A). They are made in various
sizes from 1/4 in. to 1 in. in length, whilst in regard to width they are
classed by the number of corrugations and not by their measurement.
[Illustration: Fig. 362.--Jointing Boards.]
[Illustration: Fig. 363.--Jointing a Frame.]
[Illustration: The Use of Saw-edge Corrugated Steel Fasteners.]
To use the fastener no special tools are required; it is simply driven in
with a hammer exactly as though it were a nail; once in position,
however, to get it out is worse than drawing teeth. The corrugations add
to the strength of the device, the wood fibres closing around them, age
and rust but emphasising their grip.
WALL PLUGS.--At Fig. 364 four types of wall plugs are shown: _a_, the
ordinary rectangular tapered wall plug to drive between the joints of the
brickwork; _b_, the circular tapered wall plug as used to plug a wall
after a star-shaped brick drill has been used; _d_, a twisted wall plug
used for similar purposes to the wedge _a_, but considered to be
superior in holding power owing to its twisted formation; _c_ is another
type of wall plug considered to have great tenacity by reason of its
corrugations. Wall plugs are required in nearly all cases where it is
necessary to joint woodwork to brickwork, as, for instance,
heavily-framed silvered mirrors to the walls of shops.
[Illustration: Fig. 364.--Wall Plugs, Four Varieties.]
[Illustration: Fig. 365.--Slot Screwing.]
[Illustration: Fig. 366.--Slot Screwing a Bracket.]
SLOT SCREWING, OR KEYHOLE SCREWING, is a most useful way of joining light
woodwork in such a manner that the fixing method is not exposed to the
eye. A stout screw is inserted to within 3/8 in. of the head, as at Fig.
365. In the adjoining piece a hole is bored with a centre bit and a slot
is cut with an 1/8-in. chisel. The two pieces of timber are placed
together, and by sliding the upper piece forward the screw runs up into
the slot or keyhole and secures the joint. Fig. 366 shows the application
of the joint fixing a shaped bracket to the shaped shelf; the bracket and
shelf are inverted in the illustration to clearly show the method of
jointing. For heavy work special brass plates are obtainable for this
purpose; one plate is let flush into the upper piece and the other plate
into the lower piece.
Battening (Fig. 367).--A good method of joining cross battens to drawing
boards and other wide surfaces is shown here. After boring for the
screws, slots are cut so as to allow the screws to move along the slots
when shrinkage takes place. In Fig. 368 a similar method is applied to
secure the drawer bottom to the drawer back. If shrinkage takes place in
the drawer bottom and it leaves the groove in the drawer front, the
screws are slackened, the drawer bottom is knocked up into the groove,
and the screws again inserted. For drawing boards, etc., specially made
elliptical-shaped slotted brass socket cups are made to receive the screw
heads.
[Illustration: Fig. 367.--Battening.]
[Illustration: Fig. 368.--Drawer Bottom Joint.]
PUZZLE JOINTS
Puzzle Joints are not only interesting in themselves, but are often
excellent studies in craftsmanship. The majority of them, if to be
satisfactory as puzzles, call for very careful setting out and cutting,
entailing the same degree of skill that is demanded for high-class
cabinet work. For this reason several examples may well find a place in a
volume dealing with woodwork joints. As a rule, these puzzles should be
made in hardwood, such as dark walnut or beech, as in whitewood the
joints are soon liable to wear.
[Illustration: Fig. 369.--Sketch of the Completed Chinese Puzzle.]
CHINESE PUZZLE.--The ingenious puzzle of the Chinese type shown in Fig.
369 is probably older than many of us could guess, but as it is one that
can be made by any woodworker we give full directions as to how it may be
constructed. The complete article may be called, in form, a six-pointed
pyramid. It is made up of twenty-one different pieces, each cut from wood
1/2 in. wide and 1/2 in. thick; 3/8 in. wood may be used if preferred.
For the purpose either sycamore or white maple is the most useful.
[Illustration: Fig. 370., Fig. 371., Fig. 372. The Three Cross
Pieces.]
[Illustration: Fig. 373.--Key Piece.]
The pieces required are as follows:--
Fig. 370.--Six pieces, 3-1/2 ins. long, with a half slot cut in the
centre as shown. This slot must be exactly the width of the wood's
thickness, and cut exactly half way through, so that, if two pieces are
placed across by means of the halved joint, their surfaces will be flush.
The slot must also be exactly in the centre.
Fig. 371.--Six pieces, size 2-1/2 ins. long, with a half-cut centre slot
similar to that of Fig. 370.
Fig. 372.--Six required, these being 1-1/2 ins. in length, and with slots
in the middle as before.
Fig. 373.--One of these last six requires special treatment, as it forms
the key block of the puzzle. After its slot has been cut, one half of the
narrow part must be sawn away, as shown in Fig. 373. The inner edge must
also be gently rounded. The special use of this vital piece, which we
will call the "key," will be fully explained presently.
Fig. 374.--Then, in addition to these, there are three central bars to
make. Like the other parts they are 1/2 in. by 1/2 in., but are each
4-1/2 ins. long, and are cut as shown in Fig. 374. The end projections
_a_ are 1/2 in. long, and the cut-away part is exactly half the depth of
the wood. Two of the three pieces (X and Y in Fig. 374) are similar, but
the slot _b_ of the third one (Z) is only 1/4 in. wide instead of 1/2 in.
As will be noticed, this 1/4-in. slot is _not_ in the centre, but
corresponds with the right-hand half of the larger slots of X and Y.
[Illustration: Fig. 374.--The Central Bars.]
In making these twenty-one pieces, what should be borne in mind is that
the different parts fit closely into each other. Consequently the slots,
in width, must be cut so as to grip the thickness of the wood; in depth
they must be exactly half this thickness.
FITTING THE PUZZLE.--The three central bars must first be joined, as
those form the skeleton framework of the structure. Fig. 375 shows them
in position, but as it is a puzzle in itself as to how they can be got
thus some explanation is necessary.
[Illustration: Fig. 375.--The Three Central Bars in Position.]
[Illustration: Fig. 376.--How to Adjust the Bars. (Note position of
projecting ends, _a_.)]
FIRST STAGE.--First take the bars X and Y (see Fig. 374) and arrange them
as shown in Fig. 376. It is most important that the projections _a_ of X
face upwards, and that the projections _a_ of Y face towards the centre.
Then take the bar Z and bring it flat into the slot of X. The little slot
of Z, however, must remain _above_ the slot of X. Then slide the bar Y
along to the centre, so that the part lettered _c_ slips into the little
slot of bar Z.
This may seem confusing to read, but it is easy to follow when the pieces
are in one's hand. The result of this rather clever arrangement is that
the six arms of Fig. 375 are all exactly the same length, width, and
thickness. They are also arranged so that in each arm may be clasped one
piece each of Figs. 370, 371, and 372. The three central arms may, of
course, be set up in a different order, and here we have merely chosen
the way that is the most simple to describe and illustrate.
[Illustration: Fig. 377.--Beginning to place on the Cross Pieces.]
[Illustration: Fig. 378.--Placing the Key Piece to overlap end projection
of Central Bar.]
SECOND STAGE.--In the remaining part of the work the chief difficulty is
to keep the puzzle from falling to pieces before the key finally locks
it. Take the longer cross parts, Fig. 370, and clasp one to each arm. The
six need not all be put on meanwhile, but only those which are most
easily handled. The next size (Fig. 371) may then be put on.
In the ordinary course each arm could be completed with its three cross
pieces till the sixth was attempted, and here the reader would find that,
at the last moment, his attempt was frustrated. He could not get the
last small piece in, as other bars lock the puzzle. Here it is that the
"key" comes in.
THE KEY PIECE.--When the writer fits up the puzzle he finds that three of
the arms may straight away be fitted complete with their three cross
parts. These are the ones where the longer cross piece (Fig. 370) _lies
flush with the back of the central bar_ (see Fig. 377). This is easily
found out when at work on the puzzle. In the case of the other three arms
there is, of course, a gap caused by the long slots of the central bars.
Adjust the parts on the first-named three arms, and then deal with the
fourth arm, putting in all three cross parts. For the little one here,
use the "key."
By placing the "key" so that it _overlaps the end projection_ of the arm
(see Fig. 378) a space is left at the centre, and means is thus afforded
for getting in the three cross parts on the remaining two arms.
This practically ends the puzzle. While the "key" is in its overlapping
position the parts may be separated, but if it is _turned round on its
narrow neck_, so that it is in exactly the same position as the other
five small cross parts, it locks the whole thing so tightly that nothing
but sheer force could loosen the twenty-one pieces.
So far as the order of putting together is concerned, there are many
equally satisfactory ways, these being determined by the ease or
difficulty that one experiences in holding the half-finished puzzle. It
all comes to the same in the end, and the "key" must be placed on one bar
before the last three arms can be completed. The "key," moreover, must be
on one of the bars where a gap is left at the centre, and not on one
where Fig. 370 lies flush against the central arm as in Fig. 377.
UNDOING THE PUZZLE.--To take the puzzle to pieces all that is required is
to turn the "key" half round and push the other two cross bars on that
arm towards the outer point. The cross bars below may then be removed,
and the whole structure falls to pieces.
THE DOUBLE DOVETAIL PUZZLE (Fig. 379) consists of two pieces of wood
(usually one dark and the other light) which, upon examination, appear to
be dovetailed together from each face. This interlocking arrangement is
obviously impossible, and the solution of the puzzle is only apparent on
examining Fig. 380, where it will be seen that the joint fits together
diagonally.
At Fig. 381 are given the diagrams for setting out. Draw the outline of
the elevation, plan and end view. The end view in the first instance is
indicated by 3, 4, 5 and 6, and it measures 1-7/8 ins. square. A
1-7/8-ins. square is simply used because 2-ins. wood generally finishes
this size after it is planed up. Set out a square (A, B, C, D) which
stands corner-ways in the larger square (3, 4, 5, 6). Project the lines D
A and C B upwards as at 1, and on to this drawing (1), set out the
dovetail according to your own idea of length, width and bevel. Project
the four points of your dovetail downwards into the end view, and where
these lines cut A, B, and D, C draw them downwards and rebate them into
your original plan. This will give the true shape of the two dovetails
and it is to this shape that you will cut your joint.
The joint is in due course glued up, and next day you will plane and
waste off the four corners of your model. The end view shows one corner
shaded D, 3, A; this and the other three corners are wasted away. The
result is that the dovetails are thrown into a plane different from that
in which they were made, showing as Fig. 379.
[Illustration: Fig. 379.--Double Dovetail Puzzle.]
[Illustration: Fig. 380.--The Two Parts Separated.]
[Illustration: Fig. 381.--Elevation, Plan and End View, showing how the
Puzzle Joint may be correctly Set Out.]
[Illustration: Fig. 382.--Dovetail Puzzle. The Finished Joint.]
[Illustration: Fig. 383.--Sketch of Dovetail Piece.]
(Note that dovetail is cut on slant, the thickness at front being less
than at back. See dotted line on plan below.)
[Illustration: Fig. 384.--Plan, looking upwards.]
[Illustration: Fig. 385A.--Front Elevation.]
[Illustration: Fig. 385B.--Back Elevation.]
The model calls for very accurate workmanship and the joints must not be
_undercut_ during the sawing and chiselling operations. The completed
model measures 6 to 7 ins.
THE DOVETAIL PUZZLE joint illustrated at Fig. 382 has perhaps caused more
argument and controversy amongst woodworkers than any wooden joint. It
may be neatly made in maple, walnut, or mahogany, and afterwards glued
up. The question everyone asks is: How was it put together?
[Illustration: Fig. 386.--Variation of the Dovetail Puzzle.]
Take two pieces of wood such as mahogany, walnut or birch, about 6 ins.
long by 1-7/8 ins. wide and 1-1/4 ins. thick. Truly plane them up and
then set out and make the tenon and dovetailed piece (Fig. 383). Next
mark out and cut the cross bar to fit its corresponding piece. The joint
will go together in a somewhat diagonal direction as it is pushed into
position from the back; when closed it will appear as at Fig. 382. For
guidance, a plan, part elevation and back elevation are added.
An improvement after you have gained experience in the making of this
joint is to make a similar joint, leaving the face (B, Fig. 386) blind;
it then does not show the bevelling of the dovetail at the end C. In
other words, keep the line C, say, 1/4 in. back from the face of B. The
joint should be glued up and it will then appear to the average worker
that it is an impossible proposition. (See Fig. 401, page 208.)
[Illustration: Fig. 387.--A Simple Variation of the Dovetail Puzzle.]
Carefully note that the edges A, A are parallel to each other in spite of
the fact that they slope in one direction.
A further variation of the puzzle is seen in Fig. 387. Here the joint is
much simpler, and can easily be followed from the illustration.
[Illustration: Fig. 388.--Six-piece Joint Puzzle.]
CROSS PUZZLE.--Fig. 388 illustrates a six-piece puzzle joint, similar in
some respects to Fig. 369, but very much simpler. Both a back and front
view of the piece D is shown for clearness of illustration. The method of
assembling the pieces is as follows: Hold piece B upright, and fit piece
D across; at the same time note that the small _x_ marks are opposite
each other. Take piece E and, holding it as shown, slide it up the piece
B (see arrow) until E engages D and the small _o_ marks are opposite each
other. Piece C is now fitted behind D, and then piece F will slide in
position and push downwards. The key-piece A is now put in position, and
the puzzle is completed.
[Illustration: Fig. 389.--Mortising Puzzle, showing how the Parts Fit.]
MORTISING PUZZLE.--The ordinary mortising exercise is, after the first
two or three attempts, generally voted as uninteresting, but, although
the simple puzzle shown in Fig. 389 is practically an exercise in
mortising, yet, forming as it does a puzzle, it becomes a fascinating
piece of work.
The puzzle is composed of three pieces of wood, each 4 ins. long, 1-1/2
ins. wide, and 1/2 in. thick. In each piece a mortise 1-1/2 ins. by 1/2
in. should be cut as shown at 1, Fig. 390. In one piece, marked 2, a
groove is cut on one side, 3/8 in. wide, and in another piece (3) a
similar slot, but 1/2 in. wide, is cut, and this is continued on the
other side of the groove to a depth of 1/8 in. The three pieces should be
set out on a 13-ins. by 1-1/2-ins. by 1/2-in. length of wood, as shown at
Fig. 391, and when ready sawn apart.
[Illustration: Fig. 390.--The Three Parts, with Sizes marked.]
[Illustration: Fig. 391.--How to Cut the Parts.]
The puzzle is put together as shown at Fig. 389. In the first place, hold
No. 1 piece upright as shown at A, then take No. 2 piece with slot
uppermost and push it through the opening in No. 1 piece until the
nearest side of the slot projects 1/8 in. as indicated at B. Next place
No. 3 piece on with the slot at the back as shown at C, and push it down
until it touches the bottom of the opening in No. 2 piece as illustrated
at D. The only thing to do now is to push No. 2 piece as far as it will
go to make the figure as shown at E.
In this puzzle the parts should fit together fairly tight, but should not
be too stiff.
[Illustration: Fig. 392.--Chinese Cross Puzzle.]
[Illustration: Fig. 393.--Method of Putting Together.]
[Illustration: Fig. 394.--The Six Pieces, each 4 ins. by 1 in. square.]
CHINESE CROSS.--Fig. 392 shows a variation of the Chinese cross, which is
perhaps the most fascinating of all woodwork puzzles. Take six pieces of
hardwood (Fig. 394) and accurately plane and saw them so that each piece
will measure 4 ins. by 1 in. by 1 in. Bearing in mind that all the cuts
are multiples of 1/2 in., set out, saw and chisel five of the pieces to
agree with the sketches 1, 1A, 2, 2A and 3. Leave the key piece intact.
The puzzle is of course to fit all the six pieces together so as to form
the Chinese cross or block given at Fig. 392. As a clue to the method of
assembly we give another sketch (Fig. 393) showing four of the pieces
fixed together. The reader can, if he so desires, make the puzzle to a
smaller scale by using six pieces of wood each measuring 2 ins. long by
1/2 in. by 1/2 in.
[Illustration: Fig. 395--Diagonal Chinese Cross Puzzle. (Two Pieces
required of A, Three of B and One of C.)]