Chapter III: Introduction (2)

=29. Floor Hinges.=—A device is made for hanging single- and double-acting doors by means of pivots, or trunnions, placed at the top or the bottom. The top pivot is usually inactive; that is, it has no spring or other device, and is simply a trunnion, or pivot, with the necessary plate to engage it fastened to the edge of the door trim. The bottom piece of hardware, on the other hand, is arranged with a pivot and a coil spring, and has various mechanisms for operating the door positively and silently.

In Fig. 24 is illustrated a =single-acting, checking-spring hinge=. This spring hinge is known as the _Bardsley_, and its mechanism, which is enclosed in a cast-iron box, is shown at (_a_). This box, or case, is set into the floor, the top plate being made flush with the top of the floor, as shown at (_b_). The operating bar, or pivot, of the hinge has a square end, as shown at _a_, that engages with the plate secured to the bottom edge of the door, and is connected to the mechanism by means of a crank and connecting link, as at _b_. After being set into the floor, the cast-iron box, or case, containing the spring, piston cylinder, etc. is filled with oil or other non-freezing liquid, and sealed by means of the top plate _c_. The action of the door in opening compresses the spring and operates the piston in the cylinder. The spring operating to close the door also moves the piston and forces the oil in the cylinder out through a by-pass, the flow being regulated by the adjusting screws _d_, which are on a level with the top plate. In this manner, the door is closed surely but gently, from which the hinge derives its name of checking-spring hinge. Hinges of this type can be used without any modification of the door or frame, but are not extensively used on account of their high price and the cost of application.

For pivoting the door at the top, there is provided a top pivot and plate, as illustrated at (_c_). This pivot is applied to the edge of the door stile. Both the top pivot and bottom hinge plates on the door are offset.

Double-acting floor hinges are rapidly displacing double-acting spring hinges. This is due to the fact that when the former hinges are employed the door is pivoted at the top and bottom and the weight of the door is not carried by the coils of the spring, as in the double-acting spring hinge. The floor type of double-acting hinge carries the weight of the door on a ball bearing in the box, or case, let into the floor, as shown at _a_, Fig. 25, the coil performing only the function of closing the door. The hinge illustrated is not only a double-acting hinge, but is also a checking hinge, and for this reason is known as a =double-acting, checking-spring hinge=. In operating, this spring hinge not only closes the door, but prevents it, when closing, from oscillating after the door has reached its neutral, or closed, position.

There are numerous double-acting floor hinges in the market that are not of the checking type. Some of these are the _Atlas_ and _Simplex_, made by Bardsley, the _Bommer_, made by Bommer Brothers, together with the _Chicago_, _New Idea_, _Matchless_, _Chief_, and _Columbia_, made by various manufacturers. All of these hinges embody practically the same principle, but differ somewhat in mechanism.

=30. Outside Blind and Shutter Hinges.=—The outside shutter, or blind, is still much used in the construction of dwelling houses, and a great variety of hardware is made to use in conjunction with hanging these devices. Only the most common of the many available types of this kind of hardware, however, will be treated here.

The hinge illustrated in Fig. 26 may be classed among the oldest types of shutter hinge. This hinge is made of cast-iron and is formed with a gravity-locking device intended to hold the shutter in position when opened against the building. It is known as the _Lull and Porter hinge_, and is made in various sizes that are designed to throw the shutter from 1½ to 6½ inches away from the casing, so as to clear all obstructions consequent to the various constructions. A sill catch must be used in conjunction with this hinge, in order to hold the shutter in place when closed and to prevent it from blowing open.

A similar type of hinge, known as the _Clark hinge_, is illustrated in Fig. 27. This hinge is made of cast-iron, and in three sizes, which are arranged to throw the blind 1¼, 3¼, or 4¼ inches from the casing. The hinge with the largest throw is used on brick buildings. With this hinge, as with the one just described, a sill catch must be used to keep the shutter closed.

In specifying cast-iron hinges of the types just considered, it is well to mention that they shall be extra heavy, from the fact that there are so many in the market of such light construction as to be practically worthless.

A type of the =gravity-locking hinge=, which is better than the cast-iron hinge, is illustrated in Fig. 28. This hinge is made entirely of steel, and is known as the _Stanley gravity blind hinge_. There is only one size of this hinge manufactured, and it is used for frame buildings. All of the parts of this hinge are interchangeable and reversible, so that it may be used for either right- or left-hand blinds.

There is a wrought-steel hinge, known as the _Stanley blind hinge_, which has not the gravity-locking device, but which obtains a greater purchase on the shutter. This hinge is illustrated in Fig. 29; the hinge shown at (_a_) is for frame buildings, while that shown at (_b_) is arranged for brick walls.

Another type of hinge made entirely of wrought steel, and known as the _New York blind hinge_, is shown in Fig. 30. This type of hinge has a long strap that extends on the top and the bottom rail of the shutter and thus tends to prevent the blind from drooping. This strap also strengthens the shutter by relieving the mortise and tenon of the rail and stile from the strain. The New York blind hinges are made in two styles. The hinge shown at (_a_) is intended for frame buildings, while that at (_b_) is made with an offset to throw the shutter clear of a brick jamb. These hinges are ordinarily used with blind adjusters, or fasteners, and for very high blinds, a center, or auxiliary, hinge is used.

There is another type of strap hinge similar to those just described, the butt of which consists of a pin and staple, as shown in Fig. 31. This staple is secured by driving it into wooden blocking in the brick joints. Hinges of this type are used extensively in localities where brick buildings are numerous.

=31. Inside Blind, or Shutter, Hinges.=—The use of inside blinds, or shutters, is general with the better class of domestic buildings, and for hanging these shutters, three kinds of hinges are used, depending on the number of folds in the shutter and the manner in which they fold back on each other. Usually, the _butt_ and the _back flap_, as shown in Fig. 32 (_a_) and (_b_), are used. Where the shutter has three folds, however, a _knuckle butt_, as shown at (_c_), is employed. The purpose of the knuckle butt is to cause the folds to take such relative positions as will enable them, when open, to close properly into a pocket, or recess, formed in the window frame.

=32. Invisible Butts, or Hinges.=—A =secret=, or =invisible, hinge=, known as the _Soss hinge_, has recently been placed on the market. This hinge, which is illustrated in Fig. 33 (_a_), consists of a semicircular plate, which is attached rigidly to the door section, and a movable semicircular plate on the jamb leaf, which telescopes the section on the door in closing. These hinges are invisible when the door is closed. The disadvantage in the use of these hinges is due to the fact that they have only one wearing joint; they are also somewhat complicated and expensive. As shown in Fig. 33 (_b_), they have no throw, or offset, and consequently the door does not clear the baseboard, or trim, in opening. The larger size of hinge has a throw of 1 inch, which is not ordinarily sufficient for doors. These hinges, however, have their use for such mill work as seats, secret jambs, drop, or folding, leaves, etc., and for this class of work are the best in the market.

=33. Strap and Corner Hinge Plates.=—Medieval hardware was the product of the blacksmith and the whitesmith, the former working with forge and hammer, and the latter with chisel and file, the material being wrought iron. The butt hinge was unknown, while the strap, or surface, hinge was in universal use; and, as this was wholly in sight, it naturally became the subject of decoration, chiefly in outline, but occasionally in surface ornament also. With the adoption of the butt hinge for general use, the opportunity of utilizing the hinge to decorate the surface of the door disappeared, but with the modern revival of decorative art the use of constructive metal work as a feature of surface decoration for important doors was restored. This was accomplished by combining with the modern butt a surface plate that represents the strap hinge. Obviously, the width of the butt of a hinge plate should correspond with the height of the butt hinge with which it is to be used, and both should be of the same metal and finish. The other dimensions are governed by the size of the door and by taste, as is true also in the case of corner plates. A varied and artistic selection of typical strap hinges and corner plates is given in the groups of designs shown in Figs. 34 and 35.

LOCKS AND THEIR APPURTENANCES

=34. Locks in General.=—In no other line of hardware is there such a variety of grades and types as there is in door locks. In general, locks may be designated as _surface_ and _mortise locks_, the former being secured to the surface of the door and entirely exposed to view, while the latter are let into a mortise cut in the edge of the stile. Besides these two general kinds of locks, there are several special locks, which will be fully explained. As to quality, locks may be classified in three grades; namely, _common_, _medium_, and _high grade_.

=35. Common-Grade Rim and Mortise Locks.= The =rim lock=, as illustrated in Fig. 36, is generally used for buildings of the cheapest class, such as tenements and small houses. As cheapness is the controlling factor in such goods, especially the goods made for speculative building purposes, the quality diminishes with the price. For cheap work, rim locks are used on account of their low cost and because they are easily applied. They also require no trim, such as escutcheon plates, etc., and are complete when the spindle and the knob are furnished with them. Rim locks are made in various sizes and either square or rectangular in shape, the long dimension being placed either horizontal or upright. They may also be obtained with either iron or brass bolts, and are furnished with iron, tinned, or nickel-plated keys. The cheapest grades of rim locks are made with two bolts and one tumbler, while the better grades have an additional stop and a slide bolt with three tumblers.

Rim locks are generally constructed of cast-iron, and in selecting them, a careful inspection should be made of the internal mechanism, choosing only those rim locks in which the bolts and the tumblers are constructed of steel or brass. Rim locks, however, are also made of all steel, and these are coming into general use. They present a somewhat better appearance than cast-iron locks, as may be seen from Fig. 37.

The cast-iron rim lock may also be obtained with an ornamental case. These cast-iron cases, as a rule, are finished in imitation of bronze. Such rim locks, however, are not in general use on account of their somewhat higher cost, and from the fact that their appearance is not greatly improved by the ornamentation.

=Cheap mortise locks=, or =sets=, are also largely used for the more common grades of work. They are sold in sets, that is, with escutcheon plates, etc. of steel or cast-iron, both in plain and ornamental designs, as illustrated in Fig. 38. The cheapest lock sets are fitted with pottery knobs, and the better grade, with metal knobs. All of these locks described are of poor construction, as quality is a secondary consideration.

=36. Medium-Grade Mortise Locks.=—The locks grouped under the term “medium-grade” hardware have been greatly improved in recent years and are adapted to a large range of uses, but they are especially made for residence work. In dwellings of the better class, the best types of rim locks are used for doors in attics and basements, and for closet doors, but for all other doors, the =medium-grade mortise locks= are used. These locks are provided with cast- or wrought-bronze lock fronts, are made with from one to three lever tumblers, and have drop-forge steel cases. The locks are constructed with easy springs, which allow the latch bolt to retreat within the case on one light spring when the door is closed, and when the knob is turned, to operate the latch, both springs act jointly in order to overcome the friction of the knob and to throw the bolt back to central position. The mechanism of an easy-spring, mortise knob lock is illustrated in Fig. 39.

In the group of locks embodying those of medium quality are included the three-bolt locks used for chamber and exterior doors, locks for communicating doors between chambers, and twin, or two-bolt, locks for twin bathroom or toilet-room doors, these being respectively illustrated in Fig. 40 (_a_), (_b_), and (_c_). All of these locks should be used with wrought- or cast-bronze trim, either plain or in design, and in finishes to suit. Locks for exterior doors, where security is important, should be selected with this object in view, and three-tumbler, or three-bolt, locks should be used.

=37. High-Grade Locks.=—There are a number of high-grade door locks and latches in the market for the equipment of first-class buildings, and frequently these locks are especially constructed to meet particular requirements. Among such locks are included, besides high-grade, three-tumbler locks, those that embody the cylinder principle and those that are equipped as master-key locks.

The =unit-cylinder lock=, illustrated in Fig. 41, is made by P. & F. Corbin. This hardware specialty is a new departure in lock making. The mechanism of the lock is contracted into the smallest possible space, occupying only about 1½ in. × 3¼ in. Instead of being mortised into the stile of the door, as is usual with the mortise lock, a piece is cut entirely from the stile, as illustrated in Fig. 42. In order to prevent this operation from weakening the stile of the door, the unit-cylinder lock is provided with heavy escutcheon plates that are strongly ribbed on the back, so that when these plates are secured to the stile at the top and bottom, they supply the rigidity necessary to make up for the notching. As the name implies, these locks are made in a unit, and the keyhole to the cylinder lock is located in the knob. The unit-cylinder lock is made in two styles—with dead-locking latch bolt and with additional dead bolt.

=38. High-Grade Interior Door Locks.=—In Fig. 43 is shown a type of high-grade, =mortise-locking latch= for interior doors. These locks are of the heaviest construction, and are fitted with either brass or bronze fronts. The bolts are operated with two or more tumblers constructed on an improved pattern, and are of fine workmanship. The trim for a lock of this character should be of the very best grade, with knobs of the screwless-spindle type, which will be explained later.

The escutcheons should be of the high-collar or the bracket-bearing type, and should conform to the character of the locks in quality and finish. On the most important work, it is always expedient and usually feasible to obtain expert advice from manufacturers or from dealers representing the manufacturer, whose intimate knowledge of the product will be of great assistance to the architect or owner in making suitable selections. The use of high-grade hardware requires a considerable expenditure, and the necessity for expert advice consequently becomes more imperative if the best results are to be obtained.

=39. Master-Key Locks.=—The type of lock known as the =master-key lock= is generally used for public or office buildings, hotels, and occasionally in the better class of residence work. These locks can be grouped into two classes; namely, the _Yale_, or _cylinder_, and the _lever-tumbler types_, the class first mentioned being the most desirable.

In the lever-tumbler type, illustrated in Fig. 39, the tumblers, or wards, are so arranged that each lock can be operated only by its particular key, the keys for all rooms being different and non-changeable; all of the locks, however, can be operated by a key made for the purpose, termed a =master key=. Each lock of this type has two sets of tumblers; one set is operated by its individual key, and the other, being uniform in all locks of the series, is acted on by the master key. Such locks may be obtained either in the cheaper kind, with one tumbler and twelve changes, or in the most intricate styles of hotel locks, with five tumblers and 48,000 changes in one set, and all operated by one _master key_. The cylinder lock of this type is illustrated in Fig. 44, which shows a Yale & Towne, mortise, front-door lock.

=40. Details of the Yale Type of Master-Key Locks.= The =Yale= type of cylinder lock, which is illustrated in Fig. 45 (_a_) and (_b_), is much preferred, on account of the great security it gives and the small key required by it. This lock is made in three systems; namely, the _regular_, the _concentric_, and the _paracentric_, or _duplex_.

In the =regular system=, one regular cylinder is controlled by the change and master keys, the pin tumblers being cut in two places, so that the change key brings one set of the abutting planes of the tumbler in alinement with the surface of the cylindrical plug. This plug is arranged so that a separate key is required to operate each lock, the other line of cleavage through the blocks being the same with all locks throughout the series, so that they may be opened with the same key.

The =concentric cylindrical arrangement= of this type of lock is shown in Fig. 46 (_a_) and (_b_). Here, there is a larger cylinder encircling the key plug. This is known as the master-ring, or larger, plug, and is indicated at _a_. When the change key is inserted in the key plug _b_, the lower series of breaks in the pins comes into alinement with the outer edge of the plug, as shown at (_a_), and allows it to revolve in the master ring, the cam on the inner side at _c_ actuating the lock. When the master key is inserted, the upper series of breaks comes into alinement with the outer edge of the master ring, as shown at (_b_), allowing the plug and the ring to rotate together with the turning of the key, and thus to produce the same result as that caused by the operation of the change key.

The =paracentric system=, sometimes called the _duplex system_, consists in having two separate cylinders to each lock, as illustrated in Fig. 47. One of these cylinders, generally the upper one, is operated by the change key, and the lower one, by the master key. The interior construction of the lock is so devised that each key performs the necessary function of operating the same bolt, so that the individual lock may always be opened by the change key, and all locks of the series by the master key. This latter system of lock construction is more expensive than the one-cylinder type, but it possesses an advantage in that it provides greater security when a limited number of locks are grouped in one series.

=41.= Owners or officials of large office buildings and industrial works now avail themselves of the master-key system just explained. They are able to obtain mortise locks, rim locks, and padlocks, all arranged to operate with a master key, in one series. In fine residence work, this system is also adopted. Such a system of locking is easily recognized as convenient, especially where subordinates are held responsible for certain rooms or departments to which they, individually, have access, as all of the rooms or departments may be entered by the manager or superintendent by the aid of the master key.

A series of master-key locks may also be “submaster-keyed” by dividing it into subordinate groups. In such a case, each group is operated by a master key of its own, and all the subordinate groups are controlled by a grand master key. For example, a six-story office building could be furnished throughout with locks having non-changeable keys; the doors of each floor could be operated separately by a master key; and the doors of the entire building could be operated by a grand master key. The convenience of such a system is readily apparent in large buildings where each janitor is responsible for a certain floor, and where the head janitor, manager, or owner, has control of all the locks through the grand master key.

In some instances, for additional security and for special work, the corrugations in the keyway are changed in shape so that the manufacturers’ regular type of key will not enter the keyway, or plug, thus allowing no chance for the regular type of key to operate the lock.

=42. Locks for Residence Use.=—The =front-door lock= is distinctly a lock having two bolts; namely, a _dead bolt_ and a _latch bolt_. The latter is operated by the knob, and is so arranged that, by means of stop-work in the lock front, the outer knob may, at will, be set so as not to operate the latch, the latch bolt being operated only from the outside by a key.

The cylinder type of front-door lock illustrated in Fig. 44 is the best lock for this purpose, as it provides the greatest security. This lock is operated by a convenient key of the Yale type, which throws both latch and dead bolt with one insertion into the cylinder.

Three-tumbler, front-door locks and latches are to be had at a low cost, and are used in the cheaper class of dwellings. When the residence has an inner, or vestibule, door, a similar lock is used without the dead bolt; this lock is termed a _vestibule latch_. In all cases the vestibule lock should “key-lock” with the front-door lock, so that one key will operate both. The other exterior doors of a residence should have either Yale locks master-keyed to the front door, for the better class of work, or locks of the 5-inch, three-bolt variety, that are furnished with an extra bolt in addition to the dead bolt, the third bolt being operated by a thumb knob on the inside. When a cheaper trim is wanted, a 4-inch, two-bolt lock, supplemented by a separate mortise or rim bolt, may be used.

For the first- or parlor-floor folding doors, 4- or 4½-inch, two-bolt, mortise locks are ordinarily employed. Where the doors are sliding, a 5½-inch, sliding-door lock with dead bolt and pull, or handle, is provided. The pull, or handle, is operated, or thrown out, when needed by pushing a button, or stop, in the lock. This special type of sliding-door lock is illustrated in Fig. 48.

For bedroom doors, a lock similar to that used on the minor exterior doors is usually employed. The lock for these doors may be either a 5-inch, three-bolt lock, or a 4-inch, two-bolt lock supplemented with a mortise bolt. For communicating doors, it is best to use a three-bolt, knob lock, the latch bolt of which is operated by the knob from either side. Arranged above or below this latch bolt are two dead bolts, each being operated by its respective thumb piece on opposite sides of the door. Locks of this character are made for both swinging and sliding-doors.

=43. Locks for Twin-Closet and Other Interior Doors.=—Twin, or double, doors are sometimes used between rooms in residences to deaden sound or to increase privacy. Such doors should be fitted with the same type of lock as other communicating doors, except that the lock should be provided with two bolts, the same as the lock used for bathroom doors. These locks are arranged with special trim on the abutting face of each door, this trim having only a slight projection, and knobs or lever handles projecting as little as possible, in order to avoid interference on account of the limited space between the doors. Bathroom doors are best fitted with a thumb bolt, either combined with a lock or separate.

In fitting closet doors, it is best to use a two-bolt lock about 4 inches in size, with trim on both sides, so that the door may be operated from inside in case it is accidentally closed on a person in the closet. The possibility of this happening is slight, and usually a saving is effected by using a knob latch without a dead bolt and a pair of knobs with roses.

For basement or attic doors, a cheap type of mortise lock is appropriate, or a rim lock may be used, if cost is a consideration. Where care is exercised in the selection of locks in any one building, great convenience will result from having all the different class of locks about the building of the same grade, so that they may be master-keyed in one set and thus give the owner control, with one key, of all the locks. Each lock, however, will have its own individual, or change, key, and should be selected and ordered with this object in view. Another convenience may be had by ordering each room and closet door keyed alike throughout the house, or alike throughout each floor, so that the loss of a key will cause little or no inconvenience.

=44. Hotel and Office Locks.=—The purpose and use of master-keyed locks has already been explained, but the employment of such locks in large groups, as in the equipment of hotels and office buildings, requires further discussion. The term _corridor door_ designates the entrance from a corridor or a hallway to a bedroom or an office, while _communicating doors_ are those between adjoining rooms. Frequently, these doors are double, and are then known as twin doors, while the term _closet doors_ is self-explanatory. Each of these doors requires a _knob lock_; that is, a lock having the latch bolt operated by the knob and the dead bolt operated by a key. Sometimes, in the case of locks on closet doors, the dead bolt on communicating-door locks is omitted, and a thumb bolt substituted. While all of the locks thus far enumerated are used in hotels, and most of them in office buildings, technically speaking, a _hotel lock_ is a master-keyed knob lock for doors from the corridor to bedrooms, while an _office lock_ is an inverted lock; that is, a lock with the keyhole above the knob. These latter locks are usually master-keyed, especially for the doors from the corridor to the office. Such locks as these may be master-keyed on any of the systems, as previously explained. For office work, a small key is desirable, so that cylinder locks are ordinarily employed, as the key for the operation of such locks may be conveniently carried. For hotels, however, a high-grade lever-tumbler lock with round, substantial keys is desirable, because the keys are liable to hard usage, and should not be convenient to carry in the pocket.

Hotel keys vary widely in arrangement, as well as in size, quality, and price. The kind of action, or mechanism, to be adopted in a hotel lock is frequently determined by the preference and experience of the hotel manager, and it is desirable that he should be consulted in advance; but the location and use of each door should be considered in the selection of the locks for this character of building. It will thus be seen that the subject of hardware for a hotel is one that requires the most careful consideration of the architect.

The grouping of locks in a hotel should be studied, and, usually, the best plan in large hotels is to group all of the locks on each floor under one master key and to provide a different master key for each floor, care being taken to limit the issue of master keys to the smallest possible number of responsible persons. In some cases, a grand master key is also provided that will open all the locks on every floor. This arrangement of the locks entails an additional expense, and also has the disadvantage that, in case the grand master key is lost, all of the locks controlled by it should at once be set to a new combination, in order to prevent access by the person into whose hands the key has fallen. This procedure is both troublesome and expensive.

The foregoing remarks relating to hotel locks apply equally to office locks, especially as to the arrangement for the operation with the master key. In other respects, however, the locks for an office building differ considerably from those used in hotels, for a hotel lock must secure the door both when the room is occupied and when it is not, whereas an office lock is used chiefly to secure it when not occupied. In consequence of this, certain differences in action are employed. All office locks have a latch bolt that is operated by the knob from both sides and yet permits free ingress and egress. Various methods, however, are employed to lock the door against ingress except by means of a key. Sometimes this is accomplished by means of a separate dead bolt operated by a master key from either side; in other cases it is accomplished by a latch bolt only, by providing the latter with a stop-work like a front-door lock. By this arrangement, the outer knob may be stopped so that the latch bolt cannot be operated from the exterior except by the key; and, again, the latch bolt may be dead-locked from the outside by the key. The choice of these arrangements is a matter of personal preference.

=45. Store-Door Trim.=—The technical term =store-door lock= originally designated a heavy rim or mortise dead lock, but is now applied to a combined lock and latch, the former being operated by a key from either side, and the latter by a thumb piece located above the pull handle. Such locks are made in a large variety of sizes and styles, the best being of the cylinder type, as shown in Fig. 49. In this lock, the latch is operated by the thumb piece during the day, while the dead latch secures the door at night.

Plates and handles for the combined store-door lock and latch are also made in many sizes and styles, from the plain rectangular type to the most ornamental forms. Such trim offers good opportunity for effective decoration, and no embellishment is so effective for a store’s entrance door as a pair of handsome plates and handles of appropriate design. For such trim, it is not uncommon to provide an outlay of from $25 to $30 per door. Some of the more elaborate store-door handles are illustrated in Figs. 50 and 51. The trim illustrated in these plates is very carefully selected by the architect to match the style of architecture in which the building is designed, and the finish is selected with as much care.

=46. Padlocks.=—While =padlocks= are not ordinarily included in builders’ hardware, they are extensively used for factories, stables, and other buildings of this character; thus some care should be taken in their selection. Padlocks are made in a great variety of sizes, styles, and qualities, and retail at prices ranging from 10 cents, or less, to $5. Where these locks are exposed to moisture or to the weather, they should be of bronze or of brass, with all of the interior construction of the same material. If required for great security, that is, for places where they are likely to be subjected to violence, they should be very heavy, and preferably provided with steel shackles. Padlocks constructed on the cylinder-lock principle may be obtained, and should always be used where a series of locks that are operated by separate keys and controlled by a master key is employed. Ordinarily, a selection of padlocks should be made only after an inspection of the actual samples, and not according to catalog representations.

=47. Cabinet Locks.=—The locks used in cabinetwork are distinct from builders’ locks, though they are occasionally used in the construction of the finer classes of interior finish, and, consequently, are of interest to the architect. =Cabinet locks= are made chiefly of wrought metal, and in a vast variety of kinds, sizes, and grades, so that care should be exercised in their selection. The leading kind of cabinet locks are drawer, or till, locks; wardrobe, or cupboard, locks; and chest, box, and desk locks. Special locks are also manufactured for many other purposes. For the best work, the Yale, or pin-tumbler, type is desirable where great security is required, but for ordinary uses, other types, with either flat or round keys are available. Many of the cabinet locks admit of being master-keyed, and such locks are employed on lockers in club rooms, armories, etc.

=48. Asylum and Prison Locks.=—For the doors of cells in insane asylums, hospitals, and prisons, locks of special construction are required. For this reason, a distinct class of hardware is manufactured to meet the peculiar conditions that prevail. These locks, which are designed primarily to prevent escape from the rooms, or cells, are exceptionally exposed to attempts at tampering, and are especially constructed to meet these conditions. There is an extensive line of locks for these uses on the market. This line includes both the Yale type and the lever-tumbler type of lock, and these locks are constructed with both solid and barrel keys, thus affording a wide range of selection. All such locks must be made so as to be controlled by master keys.

In Fig. 52 are illustrated types of prison or asylum locks. The lock shown at (_a_) is embedded, or built, in the jamb, while that at (_b_) is secured to the door and the keeper is fastened in the jamb.

There are numerous other patterns of asylum and prison locks, such as those illustrated in Fig. 53. The lock shown at (_a_) is arranged to operate with a double-bitted key, while the one at (_b_) is operated by means of a Yale key.

Nearly all modern locks for this purpose are operated with either double-bitted or Yale keys, and those in common use are cylinder locks. Information regarding these types of locks should be obtained in advance, so that in preparing the plans and specifications, the type selected may be clearly indicated and the arrangements made for any special construction necessary to receive them. As the approved forms of asylum or prison locks are built in the masonry during construction, they must be delivered during the early stages of the erection of the building.

=49. Bank and Safe Locks.=—Locks for the doors of burglar-proof and fireproof safes and vaults constitute a group distinct from all others. These locks embody the most complicated mechanism, and represent the highest art of modern lock making. The architect in preparing plans of buildings for banks and trust companies is frequently called on to approve or to specify the fastenings for vault and safe doors. While the owners of such buildings will probably predetermine the kind of lock to be employed, nevertheless they will be guided by the advice of the architect in the selection of some particular make. The locks used on such vaults and safes comprise _time_, or _chronometer, locks_; _dial_, or _combination, locks_; and _safe-deposit_ and _subtreasury locks_. There is also a device known as a _bolt-motor_, or _automatic lock_, which is an allied product. In the manufacture of these special locks, the skill of numerous experts and specialists is required, and as their knowledge is at the disposal of the architect or the engineer, they should be consulted in the selection of such important pieces of mechanism.

The =time lock= is illustrated in Fig. 54, and is a locking device actuated by clockwork. This type of lock is used in connection with the heavy boltwork of a safe door, to prevent it from unlocking except during certain hours determined beforehand. This lock is now recognized as an essential part of the equipment of all first-class, burglar-proof vaults and safes. In its standard form, the time lock has three chronometer movements of the finest construction, each of which is competent to actuate the lock, so that, in this way, almost absolute reliability is insured.

A =dial=, or =combination, lock= is shown in Fig. 55. The combination commonly called the _dial lock_ has completely superseded the key lock for use on safe and vault doors. Essentially, the dial lock consists of a bolting mechanism guarded by a set of changeable tumblers, or wheels. These tumblers are actuated by a spindle passing through the door, this spindle being provided on the outer end with a graduated dial. By rotating the dial in a certain manner, the dial can be set and the lock operated. Dial, or combination, locks are made in two grades, or varieties, designed respectively for burglar-proof and for fireproof safes. The lock intended for burglar-proof purposes is heavy and made to resist violence, while the other locks are smaller, simpler, and cheaper, intended only to secure the door against ordinary intrusion. Both of these locks should be absolutely “non-pickable.”

In connection with the time lock, an automatic bolt-operating device is now used on burglar-proof safes. The =bolt-motor= is a mechanism containing heavy springs and is attached to the inside of a safe door. These springs are set, or braced, while the door is closed, and when released by the action of the time lock are capable of automatically retracting the heavy boltwork of the door. This construction obviates the necessity of any spindle through the door, and leaves the surface absolutely unbroken, without any communication between the interior and exterior.

A form of =safe-deposit lock= is illustrated in Fig. 56. This lock is of a new type, and is intended expressly for individual safes, or boxes, rented by the safe-deposit companies. Such locks are nearly always provided with a guard key, which is in charge of a custodian and common to all the locks in the series. Each lock has its own individual, or change, key, however, which differs from every other key in the series. Before a change key can be inserted into its lock, the guard mechanism must be unlocked by the guard key in charge of the custodian. This makes the presence of the latter a necessary preliminary to the unlocking of the box by the renter or his authorized agent. Many styles and sizes of safe-deposit locks are made to meet varying conditions, the lock probably most used being the Yale, or pin-tumbler, variety, in which additional security is obtained by using keys of special proprietary forms. For safe-deposit boxes of large size, the dial lock is often used.

=Subtreasury locks= are intended for use on the small safety chests, or “subtreasuries,” often placed within a fireproof safe. These locks, which are illustrated in Fig. 57, are of various types and sizes, and are suitable for use on metal doors of all kinds.

=50. Care and Maintenance of Locks.=—Locks, like other pieces of mechanism, need reasonable care and attention to keep them in the best condition. As they contain moving parts, they are subjected to frictional wear and need occasional lubrication. Most of the friction, and consequently the wear, occurs in the beveled latch bolt, which may be readily lubricated. If the latch bolt is troublesome, its face and back should be cleaned with a cloth moistened with naphtha or kerosene, to remove any dirt. These surfaces should then be wiped with another cloth saturated with machine oil or, better, with vaseline. Any person can perform this simple work, and if it is done once or twice a year, it will keep the bolts in such condition that each door will close easily and quietly at all times. Another cause of trouble is the tendency of the old-fashioned knob screw to become loose, thus allowing the knob to pull from the spindle. Where such spindles are used, it is a good plan to inspect them occasionally and to tighten any loose screws. The best results from lock hardware, however, can be obtained by having all locks and hardware inspected by a lock expert about once a year.

=51. Pottery Knobs.=—=Door knobs=, which are important appurtenances to locks and latches, are made of many kinds of materials, and are fastened to the spindle in several ways. It is necessary, in order to make the proper selection of knobs for doors, to be thoroughly conversant with the various types on the market. The cheapest type of door knob is molded from several kinds of clay. These =pottery knobs= are secured to iron or bronze shanks by _leading_; that is, by setting them in molten lead, which, in hardening, secures the knob to the shank.

Pottery knobs are made in three styles, namely, _mineral_, _jet_, and _porcelain_. Mineral knobs are dark brown in color, while jet and porcelain knobs are, respectively, jet black and pure white. All of these knobs are highly glazed, and are used only with the cheapest grades of locks. Ordinarily, they are furnished with japanned mountings, or shank and rose; occasionally, however, they may be had with bronze-plated, real bronze, or brass mountings. The several styles of porcelain knobs are illustrated in Fig. 58. At (_a_) is shown the mineral knob, while at (_b_) and (_c_) are shown the porcelain and jet kinds.

=52. Wooden Knobs.=—Knobs made of wood are quite generally used. They are always turned from some hardwood, and are either stained or finished naturally. The wooden knob is usually forced on the shank by hydraulic pressure, and when securely fastened in this way makes a desirable and cheap knob. Many of the cheaper wooden knobs on the market are only glued or cemented to the shank, and, consequently, are not durable, as they pull off; they are therefore entirely undesirable. The mountings for the better knobs are made of iron, brass, or bronze, though they may be had with wooden roses. Mountings of wood, however, should not be used, as any severe side strain on the knob will split the rose with the grain of the wood. In Fig. 59 are shown two wooden knobs, the one at (_a_) having a metal rose, and the one at (_b_) a wooden rose.

=53. Cast-Iron Knobs.= Cheap locks are usually provided with knobs made of cast-iron, and, although they are strong and serviceable, they are seldom attractive. For finishing knobs of this kind, a bronze metal plating is usually employed. Cast-iron knobs are frequently made ornamental instead of plain. A typical cast-iron knob and rose are shown in Fig. 60.

=54. Stamped and Spun-Metal Knobs.=—Knobs made of sheet metal have lately come into extensive use, and they may be obtained in a large variety of designs and forms. Plain and ornamental steel knobs are illustrated in Fig. 61. Knobs ornamented in any style of design are in the market, and are artistic and usually well modeled.

=55. Bronze or Brass Knobs.=—Knobs of bronze or brass are always used in buildings of the better class, and all ornamental knobs of the higher grade are made of these materials. The best knobs are usually solid; that is, cast in one piece, with the exception that the shank is inserted. Others are made in composite form, consisting of a steel interior shell, or frame, over which is tightly drawn an external section, or covering, of wrought-bronze or brass of substantial thickness. The completed knob, if properly made in this manner, is practically as strong as the hollow-cast knob and resists bruising or other injury.

=56. Glass Knobs.=—The most expensive knobs made are those of cut glass with metal mountings. Several knobs of this kind are illustrated in Fig. 62. Cut-glass or crystal-glass knobs are very costly, the price depending on the style and the amount of cutting required and on the grade of glass used. The new method of mounting glass knobs allows for adjusting the knobs to doors of varying thicknesses, and also gives the knobs a handsome appearance, making them both durable and reliable.

=57. Styles and Sizes of Knobs.=—The pottery knobs, such as the mineral, jet, and porcelain knobs, are made only in spheroidal and oval shapes. The spheroidal knobs are 2¼ inches in diameter, and the oval knobs 2½ in. × 1¾ in.

Cast-iron and stamped-steel knobs are made spheroidal and of the box pattern, with plain and molded edges, both styles of knobs being about 2¼ inches in diameter.

Bronze and brass knobs are usually spheroidal or ball-shaped, and are 2¼ and 2½ inches in diameter. They are also made oval and egg-shaped, these latter styles being provided in two sizes, namely, 3 in. × 2 in. and 2½ in. × 1¾ in. The same general dimensions obtain for wooden and glass knobs.

=58. Lock Spindles.=—In supplying a pair of knobs, there is always included with them the _spindle_, which connects them and passes through the hub of the lock. The type of spindle generally used is the =common=, or =side-screw=, =spindle=, which is shown in Fig. 63. In this spindle, the knobs are secured by means of a knob screw passing through a hole in the knob and engaging with one of the threaded holes in the spindle. There are several holes in the spindle, so that the distance the knobs are apart may be adjusted properly. Should further adjustment be required, it is accomplished by placing thin washers at the end of the knob shank. This type of spindle is generally used with the cheap grades of trim, and should not be used in high-grade work.

There is a modern type of lock spindle, known as the =“screwless” spindle=, that permits the proper adjustment of the knobs without the use of washers and with less screws. These spindles overcome the general looseness and rattle found in the common type. A “screwless” spindle, known as the _Triplex_, is illustrated in Fig. 64. This spindle is a first-class device, and is constructed, as shown, of three parallel parts, triangular in section, which, together, form a square bar. To fasten the knob on this spindle, a setscrew in the knob bears on the center bar, and owing to their wedge form, the two side bars are forced apart and into frictional engagement with the spindle of the knob. The spindle itself is screwless, and there is nothing tending to loosen the setscrew, so that when once properly tightened, the knob will remain firm and in position on the spindle under all conditions of use. In some instances, this style of spindle has been condemned by owners and architects. This has been due largely to the fact that the mechanic did not set the screw tight against the spindle, thus allowing the knob to be easily pulled off. This is often caused by not using a screwdriver that exactly fits the head of the screw. When the knobs are put in place as they should be, this device always gives entire satisfaction.

There is another, though somewhat costly, type in the market, known as the =wrench spindle=. This spindle is illustrated in Fig. 65. As shown, the mechanism consists of a chuck, or vise-like arrangement, formed on the knob shank. When the nut _a_ is screwed on the jaws _b_, the tendency is to grip the spindle securely, the latter being solid and without screw holes. This type of spindle allows perfect adjustment.

Another type of knob spindle is the =swivel spindle=. This is used with front, vestibule, and other door locks that have stop-work, whereby the outside knob may be made operative or not, as desired. In order to accomplish this, the spindle is divided longitudinally, so that one end may rotate independently of the other.

The standard sizes of spindles for door locks, etc. are ₅/₁₆ and ⅜ inch square. Occasionally, spindles as large as ½ inch square are used for large knobs or handles, such as would be used with massive lock trim. For thumb knobs and locks and latches of this character, spindles ¼ inch square are employed.

=59. Key Tags for Hotel Use.=—Considerable confusion is frequently created by hotel guests taking with them on departure the key to their rooms. Formerly, hotel managers sought to prevent this practice by attaching to each key a large tag of iron or brass, generally serrated on the edges and made so cumbersome as to practically preclude its being carried in the pocket. Subsequently, tags made of red fiber of large size became popular. The usual forms of these large tags, whether of brass or fiber, are illustrated in Fig. 66. The use of key tags, however, is gradually being superseded by having the name of the hotel and number of the room stamped plainly on the key bow, the stamped name of the house serving for its quick identification and return by mail. The latest and best development in this detail consists in attaching to the key bow, by means of a short chain, either an ornamental disk bearing the name of the hotel and the number of the room, or a small ball, the name and key number still being retained on the key bow. In either case, the short pendant serves for convenience in the use of the key, diminishes the danger of misplacing it, and, if well designed, contributes to its appearance.

WINDOW SASH HARDWARE

SASH TRIM FOR DOUBLE-HUNG WINDOWS

=60. Sash Pulleys.=—The pulleys for the counterbalancing of double-hung, or sliding, windows, while apparently unimportant pieces of hardware, are worthy of much consideration in their selection, and in the preparation of the specifications care should be exercised to provide the best pulley consistent with the character of the work. It is good practice to furnish the millmen with a sample of the pulleys that are to be used, so that the frame will be properly mortised to receive them when the sash are hung. By this method, the necessity of exposing the case to the weather during the erection of the structure is obviated.

The common grades of sash pulleys are rough and cheap, and may be used for unimportant work and light sashes. For heavier sashes and important work, however, a better grade of larger and heavier construction should be used. It is important in specifying sash pulleys to stipulate the size of the pulley and to specify the diameter of the axle; also to state whether brass or bronze wheels and bronze faces are desired. Pulleys are supplied in 1¾-, 2-, 2¼-, 2½-, and 3-inch diameters. The required diameter of the pulley is determined by the thickness of the pulley stile and the diameter of the sash weight required to balance the sash.

The cases in which the pulleys are mounted in the cheaper grades are made of cast-iron, while in the better grades they are made of stamped metal. High-grade pulleys constructed of stamped metal are also provided; these are put together either by riveting the two faces of the pulley or by electrically welding them. The construction of a built-up steel pulley is illustrated in Fig. 67. The cases enclosing the pulleys are made of cast-iron, as illustrated in Fig. 68 (_a_), or they are constructed of stamped metal, as shown at (_b_). The ends of the facing of the case are made square, rounded, or auger-shaped, and are finished either rough, polished, or lacquered, or are faced with brass or bronze of any finish desired. The pulleys illustrated in Fig. 69 (_a_) are so constructed that the mortise in the frame may be readily formed by a special boring machine carrying three or four bits. This machine bores holes of a size to fit the several cylindrical portions of the stamped-metal case, as at _a, a_, a diagram of the mortising in the frame being illustrated at (_b_).