Basics of Woodworking
Basic joints
The most important thing in woodworking is to choose the right joint for the job: it is a waste of effort to put together a garden fence with the mortise and tenon joints used in fine furniture. Each joint has its specific application, so whether you use a dowel joint or simply nail the pieces of wood together depends entirely on where the joint is and how strong it should be.
Wood can he joined either by old-fashioned interlocking glued wood joints such as the halving, dowel or mitre joint, or by nails, screws and other special fittings. These methods are all described in this chapter. Mortise and tenon and dovetail joints are more complicated to make and are not covered here.
Whatever method of joining is used, it is essential to have the wood planed so that it is straight and square.
Halving joints
The halving joint's quite simple to make and has many applications. It is made by cutting away half the thickness from each piece so that the two pieces fit flush when they are joined. The two pieces are usually clamped and glued together. Depending on the use, the joint can be reinforced slightly with a few panel pins or perhaps screws.
Halving joints cannot be made in timber less than 20mm thick, as cutting away half the thickness would then leave less than 10mm of wood, which would break quite easily.
Marking a halving joint
Mark the two sections to be cut away. Lay one piece on the other and check that they are perfectly square with a try-square. Using a sharp pencil, mark the outline on both the top and the bottom piece. Take the top piece away and score across the pencil line with either a marking-knife or another sharp knife, using a try-square as a guide.
Mark the depth of the cut to be made on each piece; on hoards of equal thickness make these marks exactly half the thickness so an equal amount is cut away from both pieces. (On boards of unequal thickness remove sufficient to allow the thinner piece to sit flush.)
Finally, continue the face marks down one side to the half-way line as a guide for the saw.
When you are marking and cuffing halving joints, take great care to do it accurately so that the pieces fit together tightly (1). If possible, use a marking knife (2) instead of a pencil for more accurate cutting lines and when sawing, (3), remember to cut on the waste side of the line. A joint which is too tight or which does not fit can always be corrected;; too loose a joint is difficult to remedy. Make extra saw cuts 1n the middle of the wood to be removed (4) as this make it easier to chisel away the waste wood
Cutting the bottom piece
Use a sharp tenon saw to make cut inside the lines, i.e. on the waste side, to the half-way line. Make a few extra saw cuts in between to make the wood easier to remove with a chisel.
Use a sharp chisel to cut away the waste, working; from both sides to the middle. Cut fine slice gradually making the cut flat.
Cutting the top piece
For a cross-joint the top is cut exactly as the bottom, Using a saw and chisel. A T-joint or corner joint can he cut using only the saw. Put the piece in a vice and saw the waste side of the hall-way lines, to the exact depth. Be careful not to saw too deeply. Cut oft the waste by sawing along the shoulder line made with the marking knife.
No chiselling is required for corner joints; both the top and the bottom pieces can he cut with a tenon saw,
Halving joints can he used to make crossjoints, T-joints and corner joints. These are frequently used in furniture construction and also for making simple doors and frames.
Using halving joints
Corner joints
the corner halving joint is a useful substitute for the mitre joint, particularly when a mitre box is not available. It is also stronger than a mitre joint and can be used on light doors. Both parts can he cut using only a sat,, which makes it quite east to make.
If the four corner joints are made accurate the the frame should be square. Check the squareness of the frames by measuring diagonals, and adjust if necessary before gluing up. A few panel pins can he used on the joints to keep them rigid.
The simple frame can he used as a door for a kitchen or bathroom cabinet or as a basic picture frame.
For use as a door the frame needs a centre panel made of plywood or other sheet material. You can attach the panel by nailing it directly on to the hack of the frame, hiding the edge with a piece of moulding.
Crossed joints
The crossed halving joint is stranger than the dowelled cross joint. Both pieces require careful marking and cutting out with a saw and a chisel. Like the other halving joints, it is generally used with the pieces lying flat for frameworks such as doors and screens, but the pieces can just as easily he on edge, and the joints slotted together like the cardboard dividers in a wine crate.
There are many variations to the basic halving joint. (1)The joint can either be flat with both faces cut away for a flush joint, or for a deeper joint (2)
Cut into the timber edges.
The pieces of a simple spice rack, for example, slot together and are then nailed to the four surrounding pieces. Similarly, larger boards, making up the base of a simple platform bed, can slot together to make up a sturdy and rigid structure.
The ends of the boards can be left exposed with the spaces between used for storage of pillows and blankets, or they can be covered up by screwing on boards of the same depth to form a surround for the base.
T-Joints
The T-halving joint is very useful in both furniture making and in general carpentry. Because the joint is neat and flush and quite sturdy it is frequently used, for example, for the rails in old-fashioned tables. It is more often used in light frames such as tall cupboard doors to connect the mid-height cross piece to the sides. These doors are quite easy to make out of ordinary softwood. Use 20mm thick pieces for the frames, keeping the uprights narrower than the cross pieces. The central panels of thin plywood can easily be screwed or nailed to the framework to make it sturdier. The panels can be stained or perhaps covered with a fabric or wallpaper to match the room decor.
You can also make a small ladder, say for a children's bunk bed, using halving-joints. Use timber at least 25mm thick and reinforce the halving joint with a screw from the back to make it sate to climb on. Look around to see how often the T-joint is used, on large and small items alike. Its sheer simplicity is the key to its usefulness as a joint.
Halving joints are a simple and versatile way of joining timber and sheet materials to make ladders. door frames.
shelving units, and other practical household items such as these. The attractive spice shelf (right) is an example of a product that makes u e of halvng joints which slot together (above) it, form a unit: the shelves are secured ]rya surrouu nailed in to the ends of the dividers. I o make the shelf revers more stable, you can pin a piece of hardboard to the beck.
Dowel joints
The dowel joint is the modern substitute for the traditional mortise {and tenon joint,, It is particularly useful for the home handyman, as it requires very few tools and is easy to make accurately. Basically the two pieces of wood are fixed together by short lengths of dowel glued halfway into each piece. The dowels are then hidden when the joint is assembled.
Dowelling is quite straightforward as long as the marking and drilling are done carefully and accurately. The matching holes drilled in the two pieces must line up exactly so that the pieces are flush and straight when the joint is assembled.
Making dowel joints will become quite automatic after a little practice. It is important to do each step slowly and carefully in turn; to develop the right habits for measuring, marking, drilling and assembling the joints.
Dowel pegs
Ready-made dowel pegs are obtainable in three diameters, 6.5mm, 9mm and 12mm; and in various lengths from 19mm to about 75mm. The ends are bevelled or chamfered to make it easier to insert them into the holes. The pegs should have vertical grooves along the sides to allow excess glue to escape when the peg is driven into the hole.
Most woodworkers make their own pegs out of lengths of dowel. The most common size is 9mm diameter and is used for most furniture construction.
To make dowel pegs cut off the required lengths of dowel and round the ends slightly with glasspaper or a file. To allow the glue to escape make a shallow groove along the length of the dowel by placing a tenon saw upside down in the vice and rubbing the dowel peg carefully back and forth over the blade.
The pegs must fit tightly into the holes, so the diameter of the drill bit must match the dowel exactly. If in doubt about making your own pegs, buy a kit containing dowel pegs and a matching drill bit.
Marking dowel joints
Always mark the best face and edge on all the pieces before starting. This is very important in making good joints. All measurements must be from one face or edge only to make the marking on the matching pieces consistent. See page 54 for preparing and marking the timber.
First mark the location of the joint on the vertical piece (called the stile) by holding the pieces together in their final position. Transfer the marks to the edge, then clamp the two pieces together in a vice with the crosspiece or rail in the same location within the marks. Make sure the best sides face outwards.
Mark a line approximately half way across with a marking gauge, working from each face in turn. Finally, draw two lines across with a try-square, spacing them at least 12mm from the edge. Most dowel joints require only two pegs but for greater strength in a stouter framework three pegs may he needed.
Before continuing, mark the hole centres with a centre punch or a nail point as a guide for the drill.
Drilling the dowel joint
The holes can be drilled with a brace and auger bit but it is much easier to use an electric drill. Use ordinary twist drill bits or buy special wood dowel bits.
There are three points to keep in mind when drilling the holes.
1. The holes must be straight: a dowel peg at an angle will not fit into its matching hole. Stand a try-square nearby when you are drilling and use it as a guide for holding the drill vertical. Alternatively, you can buy a special dowel-drilling jig which clamps on to the wood to guide the drill in vertically.
2. The holes must be the correct diameter. Test the drill size by tapping a peg into a hole drilled in a piece of scrap wood. It should be tight enough to require tapping in with a mallet or hammer, but not so tight that it splits the wood. Use another drill bit if it is too large or too small.
3. The holes should be drilled to approximately the same depth so that the dowels will extend equally into the two members. Make the holes about 3mm deeper than half the length of the dowel pegs.
There are several ways of making a marker or depth stop to fit on to the drill bit to obtain all the holes of the same depth. The simplest is to wrap a piece of masking tape around the drill hit to mark the depth to which you want it to go into the wood. A depth stop can be made by drilling through a piece of 25mm x 25mm softwood to the full length of the drill bit, then cut off however much is required to fit over the drill bit: the distance the drill bit sticks out will he the depth of the holes. Keep the depth stops you make and mark the depth on them for use on other jobs. Most manufacturers sell a stop that can be attached to an electric drill and adjusted to the required length.
Before unclamping the pieces it is a good idea to countersink the holes slightly to locate the dowel peg during assembly.
Assembling the dowel joint
Always fit the pegs to the end of the cross piece first. Add a dab of woodworking glue to the hole, then tap the dowel peg in, preferably with a wooden mallet, or use a hammer and a block of wood if a mallet is not available. Add glue to the holes in the vertical piece and assemble the joint. Leave the glue to set before any more work is carried out on the joint.
One advantage of dowel joints is that they usually do not require clamping together. If the dowels fit correctly the two pieces can be tapped together to form a tight joint. Tap dowel pegs into a plank of wood for an ingenious coat rack.
To make a dowel joint clamp the timber in the vice and murk the position of tilt, holes to be drilled through both pieces with a try-square and marking gauge (1). then (2)punch the hole centres and finally (3) drill the holes for the dowel pegs in each piece.
BELOW: The assembled dowel joint shows the best face and side marked peg with a pencilled loop. The dowel leg has been grooved with a saw to contain the excess glue and rounded at the end to slot comfortably into the hole.
Using dowel joints
Dowel joints are often used in industry to join pieces of wood together. They are not only used for ordinary timber but also very frequently to join sheet materials like plywood, blockboard and especially chipboard.
Corner joints
Dowel joints make stronger corner joints than halving joints. Usually they are used to make a rectangular frame with two verticals (stiles) and two cross pieces (rails).
This type of framework is frequently used for making the sides and doors of cabinets. It is also often used to connect the legs and rails of tables.
To make a simple table, using dowel joints, make legs either square or rectangular, say about ill - 75mm. Make the rails, which can be slightly thinner, (about 23 x 7amm) and dowel joint the legs to the rails with two 9mm diameter dowels for each joint.
Make a simple and attractive table top from a piece of plywood or blockboard veneered with oak or mahogany or painted with gloss paint. Cover the edges of the plywood either with a, matching iron-on veneer edging or with a thin strip of moulding glued and nailed on to cover the edges. Set the nails and fill the holes for a '.mouth finished surface.
Edge joints
another frequent use of dowels is for edge-to-edge joints where, for example, a number of narrow boards are to be glued together to make up a table top. These are marked out and drilled in the same way as with other dowel joints by clamping them together face sides out and squaring lines across. The short dowel pegs serve two functions. They strengthen the joint and keep the boards from slipping up or down when the hoards are being clamped together.
Use boards which are at least 22mm thick and insert dowels approximately every 400mm, placing one near each end. Glue not only the dowels but also the edges of the boards. When assembling, clamp them up fairly tight. After the glue has set, plane off the surface slightly using a long plane, and trim the ends to size.
T-Joints
Dowel T-joints are made exactly the same was as corner joints, and are also commonly used in furniture making. One interesting way to make shelves is to connect the shelf to the vertical support using 2 dowels. It is much easier to let the shelf rest on the dowel pegs than to drill holes directly into the shelf. In this tyay, by drilling matching holes all the tyay up the insides of the uprights, it is very easy to move the pegs from hole to hole to adjust the height of the shelves as required.
Dowel joints are also used for ioining timber into contlnuous surfaces such as table tops. This type of joint Is efficient for both strength and correct alignment of edges.
Dowel pegs provide useful supports for adjustable shelves and even when nothing is placed on top still look attractive. By drilling sets of holes at regular intervals. you can move the shelves to the desired height and rest them on dowels.
Mitre joints
Mitre joints are corner joints made by cutting both pieces at exactly 45° so that they fit together squarely.
They are used most often for making picture frames: the mitre is glued and reinforced with a thin nail from each side.
Mitre joints are not as strong as halving or dowel corner joints and are therefore not used for any heavy frames. But they are frequently used at the corners of cabinet doors, where a neat 45° line at the corner looks more elegant and finished than a square dowel joint. These mitres are usually reinforced with hidden dowel pegs to give them extra strength.
Using a mitre box
make a mitre joint it is essential to have some means of cutting the board or moulding at an exact 45° angle. Frame-makers use a guillotine-like machine which cuts the mouldings at 45° with one press of a foot pedal. The easiest way to cut a 45° angle at home is to use an inexpensive mitre-box as a guide for the tenon saw. Use as fine a saw as possible; the more teeth it has the finer the cut will be.
Before using the mitre box, screw a longer piece of wood, of, say, 12mm plywood on to the base, extending it about 250mm on either side. This serves to support the end of the moulding when cutting and also protects the base from cut marks. Replace it or move it over slightly when the saw marks become too deep.
Cutting the mitre is not difficult. The only difficulty is marking the pieces correctly so that the opposite sides of the frame are exactly the same length; if they are slightly different there will be a gap at one of the corners.
Cut the first mitre, using even, steady strokes without forcing the saw. Mark the length required and replace the moulding in the mitre box. A useful hint is to make a mark or clamp a block at the cut end, to form a stop from which the other piece can he cut to exactly the same length.
The most common mistake in cutting mitres is to cut the second 45° angle the wrong way. It happens to everyone. Remember that the angles all point toward the centre of the frame when it is put together.
Assembling the mitre joint
After cutting the mitres ohen t two pairs of moulding, one pair for the sides and one pair for the top and bottom, clean off the ends carefully with a piece of fine glasspaper on a sanding block or piece of wood. Be careful not to round the edges, just sand carefully with a few strokes along the 45° angle.
Start assembling at one corner. Before joining the mitres together, drill a small hole in the end for a reinforcing panel pin, add glue to the two sides and put them together, waiting to tap in the panel pins after the glue has set.
Continue with the other three joints. The frame will not be rigid until all the joints are assembled and the glue has set.
To hold the frame together until the glue sets use special mitre clamps or, more simply, tie a piece of heavy string tightly around the frame, (see ***) .
For heavier frames such as cabinet doors use longer panel pins, several each side, or use dowel pegs to strengthen the joint.
To make a mitre joint stronger, nail in panel pins along the joint. Drive them in slightly skew' in opposing directions (as shown) for the trust ctfrt tine grip.
BELOW:. Mitre cramps are commonly used to hold picture cramps while the glue sets.
Using mitre joints
Mitre joints are used mainly to make picture frames and doors.
The method of reinforcing the corners varies according to the use and thickness of the frames.
The most common method for picture frames is to pin the corners with panel pins which can be sunk flush with or below the surface. For small frames use one pin each side but for larger ones use more, slanting them in opposite directions for a firmer grip.
A mitre joint reinforced with dowel pegs is much stronger but also quite difficult to do accurately.
An easier way to reinforce the joint is to make a series of fine saw cuts across the mitre alter the glue has set. Glue thin strips of wood veneer of the same material as the frame into the grooves, and trim off the waste carefully with a block plane after the glue has set.
Heavy frames for cabinet or cupboard doors can also be dowelled from the outside to reinforce the mitre joints. Use timber approximately 20mm thick and 73mm wide, though it can, of course, be made lighter or heavier depending on the sin and use of the door.
After assembling the frame, add perhaps one nail in each corner just to hold the frame together. After the glue has set, hold each corner of the frame in turn in a vice while drilling holes through into the other piece for the dowel pegs. Glue the pegs in place and cut them off flush.
Another versatile use for mitre joints is to apply veneer-edging to the front edges of a cabinet and to mitre the corners. The cabinet can be made of plywood, blockboard or veneered chipboard simply nailed and glued together. To give it a finished look apply the matching veneer edging with an iron, overlapping the corners. Cut through both veneers at a 45° angle with a sharp trimming knife. Put the iron back over the corner to pull away the offcuts. This gives the piece a handsome finish and is frequently used on veneered pieces like radio and TV cabinets.
Picture frames are expensive to buy and even more expensive to have made by a professional framer. To make them
yourself, all you need to do is learn how to make mitre joints and then you start to make them very simply. The money you save will enable you to go to the higher-priced frames, although very often the simplest pine frames are the most effective; it very much depends upon the object being framed.
Mechanical joints
Every piece of furniture contains nails, screws or some form of hardware. In modern furniture, screws and other fittings are often left exposed as a design feature where they can look very effective if carefully positioned.
Sometimes it is much easier and quicker to nail or screw two pieces of wood together than to mark and cut out, say, a halving joint; and mechanical fixings can be just as strong and stable as woodworking joints.
The decision to use a mechanical fixing depends on several factors, such as how much time you want to spend on a project and how fine a piece it is. A crossbrace for the shed door, for example, should he nailed or screwed, whereas the corner joint of a cabinet door should be dowelled or mitred for a professional finish.
The joints you decide to make also depend on your skill with tools. For someone who has never used a chisel it is much easier and quicker to nail or screw pieces together.
Nails, screws or other fittings can be used alone or with the traditional joints. They are very quick and convenient and often stronger than the glued wood joints.
There are so many clever and attractive fittings on the market that it is quite often better to use mechanical fixings than to make complex woodworking joints. This is especially true when working with sheet materials. A plastic block joint, for example, is an ingenious device which makes it very easy to join two panels of chipboard or blockboard together.
Nailed joints
Nailed joints are most often used for temporary projects and in construction work. For furniture and other smaller projects, nailed joints used in conjunction with glue can he very strong. Panel pins which have a small head can be sunk below the surface of the wood for a hidden fixing. See the table of available nails and sizes on page 52 before choosing the nail for the job.
Nailing wood
The size of the nail to be used depends on the size of wood. Always nail the smaller or thinner piece to the larger or thicker one. Choose a nail which will penetrate as far as possible into the bottom piece without going through the other side. Where the final look of the work is not a consideration, as in some construction work, drive the nail straight through both pieces, then bend the ends over into the wood; This makes the connection extremely strong.
If the nail is too large or is hailed too near the end of a board, the wood may-split. To avoid splitting, use finer nails or panel pins..For some hardwoods or brittle woods which split easily it may be necessary to drill holes slightly smaller than the nails to prevent splitting the wood when hammering in the nail.
One method to strengthen a joint is skew nailing, that is, hammering nails in at an angle. Where possible, nail every other nail at an alternate angle.
Smaller nails and panel pins tend to bend more easily than heavy nails. To prevent the nail from bending, support it between your forefinger and thumb until it is part-way in, then use light hammer taps to drive it in.
To drive in very small pins, use the cross-pin end of the pin hammer, with the pin heads supported between your fingers. Alternatively, push the nail through a piece of cardboard which is easy to hold while tapping in the pin.
1 For hammering a small nail, use the cross-pein end of a pin hammer.
2 Always choose a nail that is long enough to go through one piece of . timber and at least half-way into the piece to which it is being joined.
3 )nail through the thinner piece first. On work where the fixings will not show, you can bend nails over to give the join a firmer hold.
4 Skew nailing allows you to drive a nail into awkward corners.
Nailed birds are used with the timber overlapping as (1) corner or (2) T- or cross joint. Where no overlapping occurs and the parts butt up to each other instead. use corrugated fasteners (shown in 3) for a quick fixing.
BELOW: these simple shpr-upsou,be made with phi wood or timber. :".ailed-and-glued joints are the basis of theirnm>hu ,inn.
Using nailed joints
Nails are used in a variety of joints to connect not only timber but also plywood and chipboard panels.
For extra strength it is advisable to apply glue to the joint, unless the pieces will have to be taken apart later
Cross joints and T-joints
Nailed cross and T-joints can simply be overlapped or they can be made as halving joints, described on page 58. To make the joint rigid, add at least three nails spaced around the joint. Avoid nailing too near the edge or the wood will split.
Nailed T-joints are often useful in connecting two wide boards, as for this simple trestle. To make the trestles use plywood pieces at least 150mm wide with about six nails per joint, and add glue for extra strength. Me pair of trestles should be made to a comfortable height, about 600mm, to be used to support a decorating table, as step ladders, or even to support a worktop.
Corner joints
Nailed corner joints in softwood often need reinforcing with small battens, because the nails tend to split the end of the board.
Plywood does not split as easily because of the layers of cross plies, so nailed corner joints in plywood used for boxes or small drawers are usually quite strong.
Corner joints with the timber lying flat, as for a frame, should not be nailed because nails have no holding power in end grain. An easy substitute for nails are corrugated metal fasteners, which are driven in with a hammer and hold both pieces quite firmly together.
LEFT: The step-ups form an em client support for a decorating table. Space then apart as required and lay a sheet of plywood or timber on top. The step-ups could also be ideal for small children who can not reach a wash basin.
Screwed joints
Screws are the most widely used mechanical fixings. They are also used to reinforce traditional glued joints. When in doubt about how to connect a joint, use screws; properly fastened, they make extremely strong and durable joints.
For most work, use countersunk steel screws, or the more expensive brass screws if rusting or appearance is a consideration. Countersunk screws fit flush with the surface. The head fits into a hole made with a countersink hit on a drill. All screws require drilled holes, as then cannot he driven directly into the wood like nails.
Attaching screws requires much more care than hammering nails. Choose the length so that the screw extends into the bottom piece by at least half the screw length, but not so long that it pokes through the other side. It is usually best to hold the screw up to the two pieces to be joined to check its length.
Mark the screw locations before drilling a clearance hole, the same diameter as the shank of the screw, to about half the depth, and drill the bottom half of the hole with a drill bit which is smaller than the threads. In softwoods it is often convenient to drill one small hole only, but in hardwoods always drill both holes carefully.
You can usually estimate the depth of the hole by eve, but where accuracy is critical, for example when drilling in the underside of a table top, it is best to use a simple depth stop made from a short length of dowel or a 25 x 25mm batten which has been cut off to the required length.
For smaller screws up to about 19mm long you can use a bradawl to make a clearance hole in softwoods. Start the blade of the bradawl across the grain then make a hole by rotating the bradawl back and forth.
Use at least two screws per joint, spacing the screw positions out evenly and marking the positions clearly for drilling and clearance holes. When it is difficult to hold the pieces together and handle the tools at the same time, clamp the pieces together until the holes are drilled and the screws inserted.
As with nailed joints, glue strengthens a screwed joint but is only important where the screws may not be sufficiently strong by themselves. If the correct size screw is not available, a slightly shorter screw can be used and the joint strengthened With glue.
Screws are also used to attach most hardware such as hinges, locks, and drawer pulls to wood. Hold the piece of hardware in position and mark the hole locations with a pencil or a marking awl, which has a fine point especially for marking the centres of holes. Most hardware has countersunk holes which require exactly the right screw size for a correct fit.
Screw-collars fitted under the counter-sunk heads give the screw heads a finished look and the screws do not need to be countersunk. Screw collars are generally available in chrome and brass finishes for Nos. 4, 6, 8 and 10 screws.
For a professionally made screwed joint first drill a clearance hole to about half the depth of the seem using a bit the same diameter as that of the screw, then complete the bottom half with a slightly narrower bit.
1 Mark and punch the centres for the holes before drilling the first half of the clearance hole.
2 A countersink bit forms a conical hole at the top so that whet the screw is inserted it mill be flush with the surface.
3 To make sure that the boards align when they are screwed together you need to match the bottom board with the drilled top piece. When the position has beet checked, insert an awl or nail through the top clearance hole to mark the drilling hole for the bottom.
4 For smaller screws drill a clearance hole with a narrow hit, as shown, or a bradawl.
Using screwed joints
Screws are used to make or strengthen almost every kind of woodworking joint. They are particularly useful in connecting plywood and blockboard. For chipboard, special chipboard screws with coarser thread are used, which are either screwed directly in the chipboard or into special plastic connectors.
T-joints
Screws generally have no holding power in the end grain of timber, so a batten is required for screwed T-joints. Alternatively insert a wall plug in the clearance hole and screw into that as in the shelf unit above.
The screwed T-joint is particularly useful for putting up simple shelving, either directly tin to the wall for, say, an alcove, or on to timber uprights fixed to the wall. Use either 25 x 25mm or 25 x 38mm softwood for battens which are screwed to the uprights. Use 25mm thick softwood hoards for shelves up to about 1.2m length. For longer shelves use thicker timber. For wider shelves, use either 19mm thick plywood up to lm long or use 25mm thick Parana pine boards in widths up to 300mm.
The shelves can either be screwed down with a couple of small screws or can simply rest on the battens, as shown on the drawing below.
Corner joints
For overlapping boards use two of three screws per joint and for boards or plywood butted together use a batten to reinforce the joint.
This type of screwed corner joint is particularly useful in making boxes such as a toy bin of castors: use 12mm plywood sides with a 6.5mn plywood bottom screwed in place. Attach castors to each corner, then paint in bright colours and add lettering or attractive transfers Screw on knobs for handles or drill 25mn diameter finger holes. This toy box can he adapted to become a seat; simply add a lid ant cover it with a cushion.
Cross lap joint
For two hoards Iving across ont another it is extremely easy to add two or three screws to make a solid joint. Make sure the pieces are square before drilling the holes ant attaching the screws. Two temporary nails hell to position the boards correctly.
A very simple table can he made using screwed cross joints. Use 25 x 75mm softwood hardwood or plywood for all the rails and legs screw them together with brass or chrome screws with screw cups as a decorative touch and simply lay the plywood or blockboard top it place to finish.
Where extra strength is required, as in shelves built for holding fairly heat ,y materials, use plastic block joint; (top left) to connect lit e timber or sheet imaterials see tin nks cahinef), or less indent Ind equally 'fcient metal brackets (hot tom righll. The kitchen units (alone' right) are held top'll trr by a rtrt work of 90-degree metal brackets.
Corners are easy to make as long as you use the correct techique. When the pieces overlap (1) use a T-joint; when they butt togelher (2) insert a small batten between for anchoring the screws. The toybox illustrates the second technique whereas the book shelves are simple overlapped joint, and the shelves are screwed to the battens on which they rest. Note the placement of the screws (right) for the two types of construction
Joints with special fittings
With the increased use a knock-down construction in modern furniture, new fittings have been developed which make the joining of wood especially easy. Many of these are available only through the furniture trade but some can he bought at local do-it-yourself shops.
The block joint, for example, consists of two plastic halves which bolt together. They are used. two per joint, to make corner or T-joints in panel, particularly those made of chipboard. Each half is screwed to one of the panels. The joints are completed as the panels are brought together and the two halves bolted tight.
Block joints enable cabinets and wall units to he made very easily out of sheet material panels. For a simple, wall-hung drinks cabinet, for example-, use white melamine covered chipboard, available in 2.44m long panels in various widths. Use white block joints to connect the corner and cover any sawn edges with white plastic iron-on edging. Make the cabinet about 350mm high and 750mm wide. Simple sliding doors made from 3mm thick white hardboard slide in plastic tracks simply glued in place.
Metal plates are not a new invention but they are nonetheless extremely useful to connect timber or sheet materials. There are three basic shapes available in various sizes. They are connected to the wood with countersunk screws. Determine the size of strews to use by trying them in the holes. 19mm long screws arc usually adequate but in some cases longer screws may he required
Using the angle to connect panels together, a simple kitchen cabinet can he made from plywood, blockboard or chipboard. For the verticals attach the bottom edge to the floor with two brackets. The horizontal dividers are attached to the uprights with two angles on either end. The 19mm chipboard top is also attached with metal brackets. It is then covered by gluing down a plastic laminate. See page 82 for covering the edge with strippings or mouldings.
It is easy to add more shelves or perhaps pull-out wire baskets for tins and vegetables. These baskets, available at large department stores or through hobby magazines, slide on metal runners screwed to the sides.
ABOVE Metal brackets are available in three basic shapes. In addition to fit 90-degree bracket (top). brackets can be righI-an,~Ied acrd flat-fated for aonuvretnforcurn'rt (centre) and flat I--shaped (bottom) s,r remain,' pnnfs.
