Joints , Joinery & Carpentry

Basic Woodworking Joints

butt joint carpentry

1. The butt joint is the simplest of all joints in carpentry. It may be made straight or right angled, and needs nails, glue or screws to hold it together.

dowelled joint

2. The dowelled joint is basically a butt joint reinforced with dowels-lengths of wooden rod. Both halves of the joint are drilled at once to make the holes line up.

secret dowelled joint

3. The secret dowelled joint is better-looking, because the ends of the dowels do not show. The two rows of holes are drilled separately, so great accuracy is essential.

mitred joints

4. The mitred joint has a very neat appearance, because no end grain is visible. Unfortunately, it is a very weak type of joint unless it is reinforced in some way.

halving joint

5. The halving joint is used at the corners of a rectangular frame. It is simple to make, has a reasonably neat appearance, and is quite strong if glued together.

T halving joint

6. The T halving joint is a variant of the usual L-shaped halving. It is used in conjunction with the previous type of halving in the construction of simple frameworks.

x halving joint

7. The X halving joint is the third member of this versatile family. It is used where two pieces of timber have to cross without increasing the thickness of the frame.

dovetail halving joint

8. The dovetail halving joint is an extra strong halving. Its angled sides make it impossible to pull apart in a straight line, though it still needs glue to hold it rigid.

through housing joint

9. The through housing joint is used for supporting the ends of shelves, because it resists a downward pull very well. It, too, must be reinforced with glue or screws.

stopped housing joint

10. The stopped housing joint has a neater appearance, but is harder to make because of the difficulty of cutting out the bottom of the rectangular slot neatly.

Tongued-and-grooved joints

11. Tongued-and-grooved joints are most commonly found along the edge of ready made boarding. But a right-angled version is also found, for example at corners of boxes.

lapped joint

12. The lapped joint has a rebate cut in one side to hide most of the end grain. It is often found in cheap cabinet work, because it is easy to make with power tools.


13. The mortise-and-tenon joint is a very strong joint used to form T shapes in frames. The mortise is the slot on the left; the tenon is the tongue on the right.

through mortise-and-tenon joint

14. The through mortise-and-tenon joint is stronger than the simple type. It is generally locked with small hardwood wedges driven in beside, or into saw cuts in, the tenon.

haunched mortise-and-tenon

15. The haunched mortise-and-tenon is used at the top of a frame. The top of the tenon is cut away so that the mortise can be closed at both ends, and so retain its strength. Four more kinds of mortise-and-tenon joint:

bare-faced tenon

16. The bare-faced tenon is offset, with a ‘shoulder’ on one side only. It is used for joining pieces of different thicknesses.

Twin tenons

17.Twin tenons are used in very thick timber. They give the joint extra rigidity and do not weaken the wood as much as usual.

Forked tenons

18. Forked tenons add rigidity to a deep, narrow joint. The angled edge of the tenon is sometimes found in a haunched m-&-t joint.

Stub tenons

19. Stub tenons are used on even deeper joints, but are weaker and less rigid than the forked tenons shown above.

bridle joint

20. The bridle joint is used where a long horizontal piece has to be fitted into the tops of several vertical pieces.

bridle joint single dovetail

21. The box joint is quite strong and has a decorative appearance. It is used for the corners of wide frames and boxes.
22. The single dovetail, like all dovetails, is extremely strong and hard to pull apart. It is used at the corners of heavy frames.

23. The through dovetail is used at the corners of boxes where great strength and a good appearance are required.
24. The lapped dovetail is nearly as strong, but also has one plain face. It is used in very high-quality cabinet work.
25. The mitred secret dovetail is also used in very high-quality work. It looks like a mitred joint, but grips like a dovetail.
26. The lapped secret dovetail looks like a lapped joint. It is slightly easier to make than a mitred secret dovetail.

27. The cogged joint is like a dovetail with the tails subdivided into smaller tails. It is extremely strong and rigid.
28.The scarfed joint is used for joining frame members end-to-end where only moderate strength is required.


Commonly used nails:

1. Lost head nail.
Head can be punched below surface for a neater finish in fine work.

2. Round wire nail.
For work where strength is more important than a neat appearance.

3. Oval wire nail.
Oval cross-section makes nail less likely to split wood.

4. Clout nail.
Large-headed, for fixing roofing felt, etc,to wood.

5. Picture sprig.
Headless, holds glass to picture frames; also for fixing down lino.

6. Panel pin.
Small nail for securing light pieces of wood; used in conjunction with glue.

7. French nail.
For rough carpentry work; large, ugly head ensures a firm grip.

8. Masonry pin.
Hardened steel nail for fixing wood direct to masonry.

9. Wrought nail.
Soft iron nail; point can be ‘clenched’ (turned over) for extra grip.

10. Hardboard pin.
Unusual head shape countersinks itself in hardboard, can be filled over.

11. Chair nail.
Decorative head for fixing leather, etc, in upholstery work.

12. Tack.
Small nail with broad head, for fixing down carpets and fabrics.

13. Staple.
For securing wire, upholstery springs, etc, to woodwork.

Special-purpose nails:

14. Corrugated fastener.
For butt-jointing timber quickly and easily: not very strong.

15. Screw nail.
For fastening sheet materials to wood. Great holding power.

16. Floor brad.
Holds down floorboards. Great holding power, but now obsolete.

17. Joiner’s brad.
Small carpentry nail used where extra holding power is needed.

18. Cut clasp nail.
Obsolete general-purpose nail superseded by oval wire nail.

19. Needle point.
Steel pin for fixing small mouldings: head broken off flush.

20. Annular nail.
Used like the screw nail, but larger and stronger.

21. Duplex head nail.
For concrete formwork: double head permits easy removal.

22. Dowel nail.
For end-to-end hidden joints in high-quality work.

23. Chevron.
For joining corners of frames where strength and appearance are unimportant.

24. Insulated staple.
For securing telephone and other low-voltage wiring.

25. Saddle tack.
For wiring: first tacked down, then folded over and fastened.

26. Roofing nail.
For securing corrugated iron or asbestos roofing to wooden rafters.

27. Chisel-headed nail.
For fastening gutters, etc, direct to mortar.

Carpentery saws

Points per inch (ppi) refers to the number of saw teeth to the inch along the saw blade. Woodworking saws with a small number of ppi are suitable for cutting softwoods and those with a larger number should be used lor sawing hardwoods. The kerf is the name given to the width of the saw cut. The gullet is the distance between one saw tooth and the next. The gullet carries sawdust out of the kerf to make the task of sawing easier.

Hand saw.
There are 3 types of hand saw.

A. Rip saw.It is used for cutting softwoods ,working with the grain. The teeth are chisel edged to shave off the fibres of the grain. The large gullet carries the sawdust out of the kerf.
B. Cross cut saw. The saw is used to cut across the grain of hardwoods and softwoods and lor working with the grain on very hard woods. The knife point shaped teeth gives the sharper cut needed when working across the grain.
C. Panel saw. The panel saw is used for fine cross cut and jointing work and for cutting plywood, blockboard and hardboard. The teeth are a similar shape to those of a cross cut saw.

Double sided saw for cutting greenwood.
One side is flne toothed for cutting slender plants and the other has large open gullets to carry away sawdust when cutting larger timber.

Tenon or back saw.
It is used for jointing and for cutting across the grain on small pieces. The back may be brass or steel. The saw with 20 ppi is for cutting dovetails. Its blade is thin to give greater accuracy. All cuts made with a dovetail saw should be along the grain as it performs a ripping action.

Saw knife or pad saw with a keyhole blade. Metal keyhole saw blade. Both are used for cutting small irregular shapes in the middle of a board.

Flooring saw.
The rounded nose allows you to cut into floor boards without damaging adjacent boards.

General purpose saw.
The teeth are hardened and tempered. It is used for cutting wood laminates, plastic, mild steel, rubber, etc. It is a handy odd job tool but is not recommended for first class, accurate work. The handle is adjustable to enable work in awkward places and positions.

Coping saw.
It has very fine teeth and is used for cutting tight curves. Tension is applied to the replaceable blade by tightening the handle.

Fret or piercing saw.
It is similar to coping saw but is deeper to allow work with larger boards. There are many types of blade available, the choice depending on what material you wish to cut.

Junior hack saw.
General purpose saw for light metal work.

Adjustable frame hack saw.
It can take 254mm to 305mm blades. Blades are available in range of ppi from 14 to 32.

Sheet saw.
This is for cutting thicker building material such as insulation slabs and metal covered plywood. It is more accurate for cutting straight lines than general purpose saw.

Carpenter’s basic tool kit

1. Tenon or back saw.
These saws are available in blade lengths of between 203mm and 355mm (8in and 14in) with 13, 14, 15, 16 or 20 points per inch (ppi). This is used for jointing and cutting across the grain on small pieces. The back of the blade may be of brass or steel. The saw with 20 ppi is for cutting dovetails and it has a thin blade to give greater accuracy. The dovetail saw performs a ripping action, so cut along the grain on very hard wood.

2. Hand saw.
This is used for cutting larger pieces of timber. There are three types of hand-saw. The one shown here is a panel saw. It is 508mm to 558mm long with 10 ppi. Its specialist purpose is for fine cross cut and jointing work and for cutting plywood, blockboard and hardboard. The other types of hand-saw are the rip saw and the cross cut saw. The rip saw is 661mm (26in) long with 5 ppi. Its specialist purpose is for cutting softwoods, working with the grain. The cross cut saw is 610mm to 661mm (24in to 26in) long with 6,7 or 8 ppi and is specially used for cutting across the grain of hardwoods and softwoods and for working with the grain on very hard wood.

3. G cramps.
These are used for a range of cramping purposes. These cramps are available in a 25mm to 457mm (1in to 18in) range of opening and between 25mm to 203mm (1in to 8in) depth of throat. When using G cramps always place a waste scrap of timber between the piece to be cramped and the shoes of the cramps. This prevents bruising of the piece.

4. Rachet brace.
This has spring loaded jaws in a screw tightened chuck. It is specially designed for holding wood auger bits

(5). The brace is available with or without a reversible rachet in a sweep (the arc described by the turning handle of the brace) ranging from 148mm to 355mm .

5. Wood auger bits.
These are used with Rachet braces.

6. Hand drill.
This is used for holding wood and metal twist drill bits and countersink or rose bits.

7. Twist bits.
These are commonly available in sizes ranging up to 13mm. The type of steel used depends on the use to which the bit is to be put.

8. Countersink or rose bit.
This is used for countersinking drilled holes so that countersunk screw heads will fit flush with the surface of the piece you are working with.

9. Warrington pattern or cross pein hammer.
This is used for general nailing and joinery and can be used for planishing and beating metal. Weights of these hammers range from 170g to 450g.

10. Claw hammer.
This is used for general purpose carpentry, in particular, for driving and removing nails. When taking out nails, make sure that the nail head is well into the claw of the hammer and, if it is necessary to protect the surface of the wood, place a scrap piece of timber between the claw and the wood. Exert even pressure to lever the nail out.

11. Carpenter’s or joiner’s mallet.
This is used for general carpentry and cabinet work and is available in head lengths of between 100mm (4in) and 180mm

12. Handyman’s knife.
This useful carpentry knife can be fitted with a variety of blades to suit specific purposes. The blades include angled concave, convex, linoleum and hooked blades. Wood and metal saw blades can also be fitted to this tool as can a blade for cutting plastic laminate.

13. Bench plane.
There are various types of bench plane and they are available in a range of lengths and widths. The smooth plane comes in lengths of between 241mm to 260mm. The Jack plane is available in lengths of between 356mm and 381mm. The Fore plane is 457mm long and 60mm wide. The Jointer or Try plane is 561mm long. When working with resinuous or sticky woods, a plane with a longitudinally corrugated sole makes the job of planing easier because friction between
the timber and the plane is reduced. If you do not have such a plane apply a spot of vegetable oil to the sole of your ordinary plane – this will perform much the same function.

14. Surform plane.
This is one of a range of open rasp/planing tools, all of which are useful and versatile. They are primarily used for rough work but with care some reasonably fine craftmanship can be produced. Each tool in this range has replaceable blades.

15. Block plane.
This small plane is particularly useful for fine cabinet work and for planing end grain.

16. Sliding bevel.
This tool is used for setting out angles, or bevels.

17. Bradawl.
This is a chisel pointed boring tool used for marking screw positions and counterboring for small size screws.

18. Adjustable steel rule.
The pocket size variety, when fully extended, range in lengths. The larger varieties are available in either steel, glassfibre or fabric.

19. Carpenter’s square.
This is used for setting out right angles and for testing edges when planing timber square. The tool has a sprung steel blade and the stock is protected by a thin strip of brass or other soft metal.

20. Marking gauge.
This is used to mark one or more lines on a piece of timber, parallel to one edge of that timber. Some types have a mortise gauge which has a fixed point on one side and one fixed and one adjustable point on the other. Its specific use is for marking out mortise and tenon joints but it can be used in the same way as an ordinary marking gauge.

21. Folding boxwood rule.
This tool is also available in plastic. Primarily for joinery and carpentry use, it should be used narrow edge onto the timber for the most accurate marking.

22. Scriber marking knife.
One end of this tool is ground to a chisel shaped cutting edge for marking timber. The other end is sharpened to a point and can be used for scribing metal.

23. Nail punch or set.
This tool is used for tapping pin and nail heads below the surface of timber. A range of head sizes is available to suit pin and nail sizes.

24. Centre punch.
This is used for spot marking metal to give a guide for drilling. The point is marked by tapping the wide end of the tool with a hammer. Automatic centre punches are available. These are spring loaded so you do not have to tap the end of the tool.

25. Carpenter’s pencil.
This has an oblong shaped lead which is sharpened to a chisel edge so that it can be used to black in lines scribed on timber.

26. Pozidriv type screwdriver.
This tip is designed for use with Pozidriv type screws which are increasingly replacing screws with the conventional blade head. The Pozidriv screw head allows for greater contact between the screwdriver tip and the screw head – providing of course that the correct size of screwdriver is used. This makes for greater torque (twisting power) and reduces the likelihood of tool slip and consequent damage to the work.

27. Cabinet screwdriver.
This tool is available in blade lengths of between 75mm and 457mm and tip widths of between 4.8mm to 13mm. The screwdriver tip should fit the screw slot completely and the risk of tool slip will be further reduced if the screwdriver tip has been cross ground.

28. Carpenter’s chisels.
These are available in several shapes and sizes of both handles and blades. The firmer bevel edge chisels are probably the most useful all round chisels to have in a basic tool kit. Chisel handles are either of ash, boxwood or plastic. Plastic handles are virtually unbreakable on quality chisels but timber handles should be treated with care and should only be hit with a wooden mallet.

29. Oilstones.
These are used for sharpening the cutting edges of such tools as planes and chisels. There are two main kinds of oilstone, natural and artificial. Natural stone comes in several types. Artificial stones come in three grades – coarse, medium arid fine – and have the advantage of maintaining their quality.

30. Fine machine oil.
This has many lubricating uses in the workshop and is a reasonable substitute for Neatsfoot oil when using an oilstone.

31. Honing gauge.
This is a useful device for holding bladed tools at the correct angle for sharpening on an oilstone. The disadvantage of this tool is that it tends to cause wear in the centre of the oilstone rather than distributing the wear evenly over the whole stone.

32. Junior hacksaw.
This is a general purpose saw for light metalworking jobs.

33. Shoulder pincers.
These are used for pulling nails and pins from timber. If possible, always place a scrap of waste timber between the jaws of the pincers and the work piece to avoid bruising.

34. Slip joint pliers.
This tool has a thin section so that the jaws can reach into tight places. It has two jaw opening positions and shear type of wire cutter.

Carpentry tips

carpenters london
To avoid splitting wood when nailing it near the end, blunt the tip of the nail – but only slightly – by hitting it straight on with a hammer. (A tap is usually enough.)

To make it easier to drive a screw into hardwood, put a little wax polish or tallow on the point – but not vaseline or soap.

When setting a plane blade, rest the heel of the plane on a piece of white paper before sighting along the sole. This will make the blade easier to see.

When making a hole with a bradawl in any type of timber, set the chisel end of the bradawl across the grain, press it down and twist it back and forth. Do not turn it right round or let it tie along the grain.

Planes sometimes skid when used on hard or resinous woods.’ To prevent this, wipe a stick of tallow over the sole. If this doesn’t work, the blade probably needs sharpening.

When trying to loosen a stubborn wood screw, first make sure that your screwdriver blade is exactly the right size for the slot in the head, or you will ruin the slot so that it no longer grips. If the wood screw appears stuck, try tightening it a little first, then turning it back. If this fails, put the blade of the screwdriver in the slot and tap the handle sharply a few times with a mallet. As a last resort, heat the screw head with a soldering iron.

G-cramps and sash cramps mark the surface of timber, but you can prevent this by putting a block of scrap wood on either side of the work-piece under the jaws of the cramp. If you do bruise the surface of a piece of timber, with a misdirected hammer blow for example, put a piece of damp cloth over the affected part and apply a hot iron; the steam will make the wood swell back to shape.

Place a scrap wood block under the head of a claw hammer or a pair of pincers when using them to remove nails. This prevents you from damaging the wood. It improves the leverage as well. Draw the nail along the grain and towards the centre of the length of timber.

Curly-grained timber often chips during planing. To avoid this, set the blade very fine and plane along the evailing direction of the grain while holding the plane at 45 degrees to the way you move it.

Second-hand or re-used timber is generally full of hidden nails and pieces oi metal that will ruin a saw, chisel and plane blades. Go over the surface thoroughly with a disc sander fitted with coarse paper, or with a surform, to reveal most of them.

Large holes in timber are best filled with ‘Dutch putty’ – cellulose filler such as Polyfilla thinned with emulsion paint. This dries hard and much stronger than plain filler, and can easily be coloured with emulsion paint tinters.

When planing uneven timber, draw two or three pencil lines down the surface before you begin. These will then be planed off at the high spots first, revealing their location.

End grain planed without a shooting board tends to split. Avoid this by planing from the edges inwards; if you can’t do this, bevel the edges all round first.

If you run out of G-cramps on a job, improvise with sections of car tyre inner tube used like giant rubber bands. Alternatively, use sash cord (but not nylon clothes line) with a piece of dowel passed through and turned to twist it tight.

A simple way of fixing a batten to a wall so that nothing shows is to drive a screw into a plug in the. wall leaving l2mm protruding. Drill a l2mm deep hole the width of the screw head in the back of the batten below the centre, and cut a slot the width of the screw shank upwards from this hole to the centre line. The batten can then be fitted and tapped down.

Wood bits designed for handbraces can be converted to excellent power tool bits by cutting off the square top of the shank, filing three small flats around it to accept the three jaws of the chuck, and filing the screw thread off the tip.

Butt joints in timber can be strengthened by driving slightly over-length nails right through and clenching (bending over) the protruding points. This must be done along the grain, so that the point sinks right in, and with the head of the nail supported, so that it is not driven back out of the wood. This creates a much stronger joint than a straight through nail.

Always nail or screw through thin timber into thicker timber to give the fixings maximum holding power.

To divide a board into an equal number of widths (say seven), set a rule across the board at an angle so that the 0 mark touches one edge and the 7 mark the other. Then mark the positions of marks 1-6 on the board. To allow for the thickness of the saw blade, hang the 0 and 7 marks off the edge of the board by half the blade thickness on either side, and saw exactly down the middle of the marked lines.

To cut a very short piece off the end of a length of timber and across the grain (in this situation the piece being removed tends to break, causing the saw to slip out) clamp a piece of scrap wood alongside and saw through both.

When fixing shelves to a wall, don’t rely on the skirting to indicate a horizontal line. For short shelves, use a spirit level. For longer ones, temporarily pin (or get a helper to hold) one end of a chalked string to the wall. Stretch out the free end of the string taut and hold a spirit level underneath it, then move the string up and down until the level shows it is exactly horizontal. Hold the free end to the wall, then twang the string against the wall to mark the line. It is essential that the string is taut.

Fitting a mortise lock

This is a simple operation well within the capabilities of any handyman. As in all aspects of carpentry though, special care should be taken in marking out, and only the correct tools for the job used. First work out where the lock is to go. In most cases it should be fitted midway up the door, which allows space further up for the addition of a rimlock or safety chain. If another lock is already fitted at this point, it can easily be unscrewed and located higher up. Mark out the position of the lock and its area, by holding it against the door at the correct location.

Remember to allow for the thickness of the face plate and mark in the correct position of the keyhole. Now, using a mortise gauge, calculate the width and height of the mortise and mark out these measurements on the edge of the door. Particular care should be taken to centre the mortise in the door so that it is the same distance from both surfaces. Most of the mortise can be cut out by boring with a brace fitted with a bit exactly the same width as the lock. To assist in boring accurately, a centre line is drawn down the area to be cut away and the centres of the holes marked in. This is best done by carefully marking out with the aid of a 45 degrees combination square or adjustable bevel gauge as follows.

Lay the bevel edge against the side of the door, and adjust its position so that one edge of the rule meets one corner of the area to be cut away. Draw a line from this point to meet the opposite side, then reverse the square and, using the same technique, draw in another line from the point where the first line crossed the edge of the mortise housing. Repeat this procedure along the whole length of the area to be cut away, then mark in the points where the diagonal lines cross the centre line to give the bore centres. Fit the bit with a depth stop so that the depth of each bored hole can be gauged correctly.

If you do not possess this fixture, an alternative is to tie a piece of tape to the bit at the correct point. Bore out each hole to the required depth, ensuring that the bit is held at right angles to the door edge. A simple way of checking that the bit is held horizontally is to place a large washer over the bit. If the washer moves towards you as you drill, the bit is held too low; if the washer moves towards the door, the bit is held too high. The bit is horizontal when the washer does not move. When you have bored the mortise out, clear the hole with a chisel. Keep to the marked lines and don’t try to remove too much waste wood at once. Instead, chisel out a little at a time and keep testing for size by fitting the lock into the mortise.

The lock should just fit with no play. Alter checking that the previously marked locations of the keyholes are correct, remove the lock and bore them out with a bit slightly larger than the diameter of the keyhole on the escutcheon. Do not bore right through the door from one side; reverse the direction of boring before the bit emerges through the wood. Clean up the keyholes and, if necessary, cut them to shape with a coping saw. Now insert the mortise lock in position and test the action of the key in the lock. If it turns smoothly, fit the escutcheons in position over the keyholes. Secure the lock in the mortise by fixing screws through the holes on the face plate. Cutting the face plate rebate insert the lock into the mortise so that the face plate is flush against the edge of the door.

Mark out the extent of the rebate by marking round the face plate with a handyman’s knife to the required depth. Take a chisel with a blade exactly the same width as the rebate and make a series of cuts down the length of the rebate. This allows the rebate to be cut out in small sections. Hold the chisel at a flat angle against the door and remove each section with very light blows from a mallet. When the rebate has been cut to the required depth, clean up the edges and insert the lock but do not secure it with screws.

Fitting the striker plates

The striker plate is recessed in the door frame in exactly the same way as the lock. To mark the correct position, first turn the key to extend or ‘shoot’ the bolt, pull the door to and mark out round the bolt (and the latch if the lock is fitted with this feature). Following the same procedures that were used to mark and cut the mortise for the lock, cut out the recesses for the bolt and the striker plate and screw this piece into place. The fitting is now complete and the lock ready for use.


Like any other fixture with moving parts, the lock should be lubricated at least twice a year. A light oil or powdered graphite inserted into the mechanism through the keyhole should ensure the smooth operation of the lock.

Choosing a mortise lock

Always buy a type of lock which is approved by insurance companies. They are more likely to accept an insurance risk on a house fitted with these locks and, in the event of a break-in, view a claim more favourably. Don’t assume that burglars only break into houses that are filled with valuables; virtually every house possesses something of value such as a television or computer.

Although your choice of mortise lock will be determined by how much security you want, a general guide is to fit deadlocks on external doors and latched mortise locks on internal doors. Even a mortise lock can be picked or sprung by an expert, but the chances of this happening are remote if you choose a lock with a complex mechanism. This is largely determined by how many levers and/or tumblers the lock is fitted with, and this number is usually stamped on the faceplate.

What is a mortise lock?

Though their locking mechanisms vary,they are all intended to be recessed into the door. Not only does this give greater security, it allows a neater finish to the door. Some mortise locks are fitted with handles and latches, others, usually called deadlocks, are without these features and consist only of a bolt and its locking mechanism. Mortise locks for sliding doors are available and these are fitted with hooked bolts which lock in position over a catch on the striker plate.

Doors and locks

No matter how thief-proof your locks are, they give only an illusion of security if they are flitted to flimsy doors. Sometimes, locks which would deter a master criminal are flitted to doors which can be broken down by one hefty push. Mortise locks have the advantage that even if a housebreaker removes a door panel he cannot open a mortise bolt from inside, except with the proper key. However, before flitting the lock, the householder should examine the door not only to see if it is sturdy, but ‘also to see whether it will take a mortise lock. Mortise locks are recessed into a solid base and for this reason cannot be fitted to some types of hollow door. All solid doors are suitable for modification and most hollow doors are fitted with a solid wood panel in the lock area, which is capable of taking a recessed lock. If your home is equipped with hollow doors, you must check on the presence of this plate by tapping the door round the proposed location of the lock. If it sounds hollow then it is unsuitable, unless you add a solid wood core to the lock area. If it sounds solid it is probably suitable, but to make sure, bore one or two holes from the edge of the door to a depth of 100mm.

Door locks

The security of your home is almost completely dependent on the locks with which it is fitted. Despite the increased number of break-ins, many householders still depend on inadequate and antiquated locks to safeguard the home. Mortise locks-types of which are approved by insurance companies-provide good domestic security and are easy to fit and maintain. This chapter describes the various types available and how to fit and maintain them. Judging by official police statements, it is surprising how many householders still depend on inadequate locks to safeguard their homes. They tend to think that the sight of a lock-any lock-will deter the would-be burglar, even though their homes may be filled with valuables.

Of course, this isn’t true; some types of lock, such as rim locks, can be opened in a matter of seconds by the professional burglar equipped only with a few bits of plastic and wire. This is not to say rim locks and other types have no uses; fitted in conjunction with a proper security lock, they give added home protection. What types of lock then, give the sort of protection which insurance companies insist on? The variety is so large as to be bewildering, but the most secure locks all incorporate certain features which will baffle anyone but a Houdini. Firstly, a secure lock, apart from having a sturdy construction, has a mechanism complicated enough to defy attempts to ‘pick it’. Generally it incorporates several levers or tumblers arranged in such a way that only a particular and unique pattern of key will open it. Secondly, the lock is recessed into the door in such a way that only the keyhole is visible on both surfaces of the door. This prevents anyone from unscrewing the lock or forcing it with a lever. Several types of locks incorporate these features, but the one most commonly used is the mortise lock.

Other types of hinges

Special problems in fitting doors and windows may call for special types of hinge. For example, a door or window that has to fold flat against a wall needs a ‘parliament’ hinge. This has an offset pivot that moves the door well away from the face as it opens, allowing it to be opened much further than normal. It makes the door swing very wide in the first few inches of opening, so that the lock side needs a heavily angled bevel cut on it. Casement windows often have a rebated edge and frame to keep the rain out. These must have a special L-shaped hinge called a ‘stormproof’ hinge

Unlike butt hinges, these come in left- and right-handed versions, depending on which way the window opens (though of course, they are generally bought two pairs at a time for paired windows). They are installed in the same way as butt hinges, but the window frame can be a looser fit than usual, since the rebated front seals it.

In houses with irregular floors or thick carpets, there is often a problem with the door catching on the floor as it opens. If enough wood is taken off the door to clear it, the wind whistles through the huge gap underneath. The solution is to use ‘rising butt’ hinges, which raise the door as it opens.

To stop the top of the door from catching on the frame as it rises, a special tapered bevel has to be cut along one-third of the length of the top edge of the door at the hinge end. The only way to get the shape of the bevel right is by trial and error removing a very little wood at a time. The length, angle and depth of the bevel vary with particular installations. The hinge is installed like a normal butt hinge, so if you hang the door temporarily on single screws and keep taking it off, planing a bit more wood off and replacing it, you should soon get the shape of the top edge right. Certain types of hinge are installed in plain view on the front (or back) of the door. These include the long sheet-metal hinges found on cottage and outhouse doors, and special self-closing spring hinges, which have such huge pivots that it would be impossible to hide them. Both types are very easy indeed to install, because the screws are exposed and you don’t have to keep taking the door off to get them positioned correctly.