Care of a Longcase Clocks

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FINE ANTIQUE CLOCKS.
Established 1968.
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Care of a Longcase Clock

including setting up and dial restoration

Whenever a longcase clock was produced, be it in the 17th, 18th, or 19th centuries, it was designed and made to last for several hundred years, provided reasonable care was taken of it. We find this concept difficult to comprehend in this throwaway age where five years is considered quite a long life for many mechanical and electrical goods. Longcase clocks are rugged and well engineered. However, an understanding of the basic care and maintenance they require is desirable if we are to pass them on to successive generations in at least as good a condition as when we received them. This is really a very small price to pay for the pleasure they have given us during our lifetimes.

Click on Heading you require

Painted Dials.
The Movement.
The Case.
Dismantling a Longcase Clock.
Setting Up Your Clock.
Regulation—If the Clock Loses.
If the Clock Gains.
Never move the hands backwards
Striking.

Rack Strike.
Count Wheel (or Locking Plate) Strike.
Correction of the Count Wheel.
Position of the Count Wheel.
Winding: Thirty-Hour Clocks.
Eight-Day Clocks.
Calendar Work.
Moon Discs.
Summary.

Clock Dial Restoration Brass Dials

When a brass dial was made by a clockmaker, the dial plate and spandrels almost invariably were polished and then protected with a coat of clear lacquer to prevent them from tarnishing. The only exception to this is the use of fire gilt on some of the finest early clocks. This is the deposition of a layer of gold on the dial by making an amalgam of gold and mercury, applying this to the dial, and then driving off the mercury by heating it up to a high temperature over a charcoal fire. Because of the obvious danger to the worker's health because of the mercury fumes, this process has been banned for many years. After the dial and spandrels were gilded, the high spots were burnished to give depth and lustre to the finish. Fire gilding as opposed to electroplating will last for many hundreds of years and should on no account ever be removed from a dial.
    The chapter, seconds, and date rings of dials and the name plaque (where present) were almost invariably silvered in the first instance to make them easier to read. This was achieved by the chemical deposition of silver onto the surface of the brass followed by polishing with cream of tartar and then protecting it with a coat of clear lacquer or varnish. This process should not be confused with electroplating, which must never be used on old clock dials.
    The question "Won't I reduce the value and originality of a clock if I restore the dial?" is often asked. The answer to this is that the dial will almost certainly already have been restored several times during its lifetime, so the finish you are looking at is not original anyway. It is the originality of the dial itself which counts.
    Brass and silver, when they do tarnish, often do so unevenly, possibly because they have been handled or the protective lacquer has broken down in places. They gradually turn a brown/black color which can only be regarded as unsightly. Nothing is to be gained by retaining this any more than you would leave a pair of brass candlesticks unpolished. Whereas wood mellows with age and takes on warmth, metals such as brass and silver just oxidize and discolor and thus need regular attention.
    Once restored a dial must not be polished otherwise the protective lacquer will be breached and the metal will start to tarnish. On no account should a dial ever be cleaned or restored unless it is stripped down first. To attempt to do so will inevitably leave chemicals underneath the chapter ring, spandrels, etc which will in time cause corrosion.

Painted Dials
The term painted dial is somewhat misleading as it gives the impression that the dials were painted in a similar way to that which we would do today. However, such is not the case and far more time and trouble was expended on the meticulous preparation of the background in particular, heat being used to produce a hard finish. Layer upon layer of paint was used, each one being rubbed down when hard and a further coat applied until gradually a perfect serface was achieved.

The description "enamelled" rather than "painted" dial is probably the more suitable term as it gives a better idea of the technique used and the finish obtained but it should not be confused with the hard enamels employed for clock dials on the Continent. These were fired, usually onto copper, at much higher temperatures.
An extract from "A visit to a Clerkenwell Clock Factory" which appeared in The Illustrated London News, 20th September 1851 gives some insight into the process:

"The dial faces are coated with what is technically termed white-flake, a superior kind of white-lead, which is ground down with the finest description of Copal Varnish, and then put into a stove, similar to that used by Japanners, until it becomes sufficiently hard to receive a polish, which is effected chiefly with pumice stone, by which means a most perfect surface is produced, ready to receive figures, which are painted with lamp black, varnish and turpentine."

The restoration of a painted dial is very like that of a painting and a similarly cautious approach should be employed. So far as possible the original background, which usually is in reasonable condition, should always be retained, touching in where necessary and similar remarks apply to the corner decorations (spandrels). However, the numerals and the name which are not as durable, will often have become worn. If this is not too bad then they can just be sympathetically restored but if extensive then they may have to be completely redone. Fortunately this is relatively easy to do because of the way in which the dial was originally painted.
The remains of the existing numerals can be removed fairly easily, just their shadows remaining to act as a guide when repainting.
Quite frequently when restoring a dial, a makers name can be detected on what was thought to be an anonymous clock. The best way of doing this is to vary the angle of the dial relative to the light source until the shadows of the original name can be read. Once one has picked up some of the letters, reference to guide books listing clockmakers such as Baillies & Loomes should give you a clue to any which are difficult to decipher.

The Movement
The movement of the longcase clock is designed so that steel pinions mesh with brass wheels. This combination requires no lubrication; in fact, if oil is applied, considerable damage will ensue over a period of time as dust and dirt will stick to the oil and be forced between the wheels and pinions, greatly increasing their wear. Oil or thin grease is only required where there is a sliding friction between two parts, and then only sparingly. Examples of this are the faces of the pallets which engage the 'scape wheel and possibly the block on the pendulum which passes through the fork on the crutch. These can safely be attended to by the owner every few years. A thin grease is also often used on other components which slide against another, such as parts of the strikework, but this can only be carried out by the clockmaker when the clock is dismantled. It is difficult to guess how long a clock may be left before cleaning as it varies so much with temperature, humidity, and the dust and dirt in the atmosphere. However, probably a reasonable regime is to oil it every three to five years and strip and clean it every ten years. Although the clock will continue to go after this, it has by then become dirty and is grinding this dirt into its wheels and pinions.
The only other part of a longcase clock which requires attention from time to time is the sinks around the pivot holes. Just use a little oil there. However, as this necessitates the removal of the dial to reach those behind the front plate, the work is usually best left to a clockmaker.

The Case
    Never subject a clock case to a dry atmosphere. In cold climates where central heating is used in the winter, conditions that are too dry can occur. As soon as the relative humidity (RH) drops below 55 percent, the wood starts to shrink, the doors twist, veneers crack and great damage is done to the case, much of it, sadly, irreversible. In the last 20 years more damage to antique furniture in general has probably been caused in this manner than has occurred in the previous 300 years due to cold, damp, draughty houses and general neglect. The pity is all the greater in that it can so easily be avoided by the use of humidifiers, the cost of which is far less than the cost of restoring fine antiques. Indeed, it seems to be a pattern of advancing civilization that we damage so much of our environment and heritage, not willfully or by neglect, but by thoughtlessness. So far as the preservation and even the improvement of a clock case is concerned, the best approach is to apply a beeswax polish a few times a year and spend the rest of your time just polishing and burnishing it. If too much wax is used, dust and dirt will stick to it and in time obscure the figuring and color of the wood.
    A practice which has been advocated now for several hundred years is to gently wash the case once a year with a weak solution of vinegar water. This lifts the surface wax and with it the dirt which has accumulated without going through the deeper layers of wax and reaching the wood. After this has been done the case is carefully dried, rewaxed, and polished.
    Besides applying wax to the outside of the case, the inside can also be treated and left unpolished. The advantage of this is that if the wood starts to dry out, then the wax will be drawn into it and reduce, to some extent, the risk of further damage to the case.

Dismantling a Longcase Clock
A longcase clock should always be dismantled before it is moved. First stick a small piece of paper on the backboard immediately behind the tip of the pendulum. Then stop the pendulum and mark the position of its tip on the piece of paper. When the clock is reassembled, if it has been put together correctly and nothing (particularly the crutch) has been bent or disturbed, then, provided the tip of the pendulum corresponds with the mark on the paper, the clock should go. The pendulum acts as a plumb line and determines that the case is upright.
    Having noted the position of the pendulum, the next step is to remove the hood. This may be locked in place by a turn buckle or bolt fixed to the trunk immediately below the front of the hood. This is reached by opening the trunk door and feeling up inside. Sometimes a wooden bar is used which will usually be apparent when the door is opened.
The hood may now be slid forward and removed. The only exception is on a few very early clocks made prior to circa 1690 which still have lift-up hoods and are held by a catch in their raised position for winding. Although they are usually locked down by a spoon latch, this is automatically released when the trunk door is opened.
    To save the lines supporting the weights from getting tangled, particularly inside the movement, these are best let down. By far the easiest way of doing this is to keep the clock running until it stops with the weights at the bottom of the case. Should this be impractical, it is best to remove the pendulum first. This is achieved by lifting it up about one-half inch, if possible by the small brass or steel block above the steel strip, then moving it back so that the steel strip comes out of the slot in which it is engaged. Great care is needed at this stage not to damage it. Finally, the pendulum may gently be lowered, allowing the suspension to pass down through and out of the crutch. It can now be removed from the case and carefully fastened to a length of wood to prevent it from being damaged. Particular attention should be paid to the steel suspension; a useful ploy being to fix two small pieces of wood on either side of it.
    Before unhooking the weights it is wise to get a friend to hold the movement steady in the case. The movements are front-heavy due to the dial, and as soon as the weights are removed, tend to fall forward out of the case, which does neither the movement nor the owner any good if it lands on his head. Nearly all clock dealers and restorers have suffered at least once in this way.
    Having taken off the weights, the lines can be let down. This is done by releasing the clicks engaging the barrels, either by pushing the other end of what is usually a pivoted lever or, if this is not possible, by lifting the active end of the lever out of engagement with the dog-toothed ratchet wheel. Sometimes this is simplified by slightly winding the wheel with the key so as to lift the end of the lever up to the tip of a tooth where it can be more easily engaged.
    As soon as the lever is disengaged, the lines can be gently pulled offthe barrel. It is not normally advisable to let the lines down with the weights still on as they may crash down to the bottom of the case.
    Should the lines get tangled, untie the free ends, remove the pulley, and uncoil the line from the barrel turn by turn. The movement, complete with its seat board, may now be removed from the case and put safely in a box, care being taken to see that the crutch cannot be damaged. Occasionally the seatboardwill be held in place with screws which will obviously have to be removed first. Where the seatboard is nailed down, particularly if this is with the original clout nails, then it should not be disturbed for fear of damage. In these instances it is usually best to untie the lines where they pass through the seatboard, pull them out, remove the pulleys, release the two bolts or hooks holding the movement down, and then remove it.

Figure 1.
Setting Up Your Clock
    It is nearly always desirable to fix your clock to the wall. If this is not done, apart from the risk of its being knocked over, when the weights are roughly half way down (nearly level with the pendulum bob), they will pick up its motion and rock from side to side and result in the pendulum stopping.
    On a solid floor it is sometimes possible to avoid fixing the clock to the wall by just chocking up the front feet approximately three-eights of an inch off the floor. The weight of the clock will then be thrown back against the wall and make it relatively stable.
    A longcase is usually best situated flat against the wall as opposed to across a corner. It can be fixed there by screwing a piece of timber approximately eight-by-two-by-one inches horizontally to the wall and then fixing the clock to this. (See Figure 1.)
    Should your skirting board be thicker than one inch, the piece of timber will have to be increased in thickness correspondingly. The case may be conveniently fixed to the piece of wood, either behind the hood, or more simply, behind the trunk door. Frequently there are holes already in the back of the case. In such instances the batten can be fixed at the same height.
    When a clock has to be set up across a corner, a bracket such as that shown in Figure 2 should be used.

Adopt the following procedure after getting the clock home.

1. Decide where you want to place the clock and then fit a convenient batten.

2. Place the case in front of this, get it upright, and fix it to the piece of wood.

3. Place the movement in the case, preferably with the lines which hold the weights fully extended. Get a second person to hold the movement while one of the weights is put on to steady it.

4. Put the hood on. Then, by sliding your hand up inside the case, position the movement so that the dial is correctly positioned inside the hood with the latter fully seated.

5. Remove the hood, taking care not to disturb the movement, and put on the second weight (if applicable). The pendulum may now be fitted by putting it inside the case through the trunk door and then feeding the strip of spring steel behind the movement through the steel loop or fork at the back of the movement (known as the crutch). Then hook it onto the brass bracket above by sliding the steel through the slot and letting it down until the small brass block at the top of the spring rests on the bracket (Figure 3).

Figure 2.

Figure 3.

6. Carefully wind up the weights, making certain that the lines are not twisted and are winding evenly onto the barrels.

7. Do not wind the weights up as far as possible. Always leave a gap of about two inches between the underneath of the clock and the pulleys.

8. Mark on the backboard of the clock the position where the tip of the pendulum hangs, then move the pendulum first to one side and note or mark the position when the dock "ticks" or the second hand just goes on one second and then repeat the procedure on the other side.

    The "ticks" should occur evenly on either side of the original mark where the pendulum hangs. If it is too far to the left, then the whole clock must be tilted a little to the right until the "beat" is even on both sides.
    However, for obvious reasons such as appearance and the pendulum hitting the side of the case when it swings, this can only be done to a very limited extent. The best method is to bend the crutch at the back of clock. This is the way in which a clockmaker would normally put a clock "in beat," but it does require care— otherwise the crutch or the escapement may be damaged.
    The crutch is bent in the opposite direction to the side on which the pendulum has to move farthest before the clock ticks. This is a delicate operation and the crutch will usually require several adjustments before the beat is even. (Figure 4). Unfortunately, the strength of crutches varies greatly, some bending easily and others only with appreciable force.

Figure 4.

Regulation—If the Clock Loses:

1. Stop the pendulum.

2. Raise the bob a little by turning the regulator nut below it (see Figure 5).

3. Move the hands forward to the correct time and start the clock by swinging the pendulum.

4. For precise regulation of the clock, let the pendulum swing until the seconds hand is at top dead center (on 60 or 12). Move the minute hand until it is exactly on a minute division. Start the clock by holding the pendulum to one side and releasing it when the time signal is heard on the telephone, radio, or television.

If the Clock Gains

1. Stop the pendulum.

2. Lower the bob a little by turning the regulation nut below it.

3. Wait until the clock reads correct time and then restart it. Alternatively it can be left until it reads slow and then the minute and hour hands advanced to correct time before restarting the clock.

NEVER MOVE THE HANDS BACKWARDS.

NB: Regulators and all 30-hour clocks have a form of maintaining power which keeps them going whilst they are being wound, but the movement of nearly all others stops and loses this amount of time. Ideally, if it takes (for example) 20 seconds to wind the going side of a clock, then it should be adjusted to gain 20 seconds during the week to allow for this.

Figure 5.

Figure 6.
Striking
1. When moving the hands always let the clock strike each hour. Similarly, if it chimes at the quarter-hour, let it chime each quarter in full. It is essential with all clocks fitted with a count wheel (sometimes called a locking plate) strike to let them sound out each hour in full. Otherwise, the strike will go out of synchronization with the time and have to be corrected.

    It is extremely important in clocks fitted with rack striking to let them strike 12 in full as this allows the clock to reset itself for a further series of 1 2-hour strikes.

2. When turning the hands always move them slowly for a few minutes before you come to the hour. When a "click" is heard pause for a few seconds to allow the clock to prepare itself to strike the hour and then gradually move the hand up to the hour. Allow the hour to be struck in full before moving the hands further.

Rack Strike

With eight-day longcase clocks made in London after circa 1700 and in the country at a somewhat later date, a system of striking known as "Rack Strike" was employed in which the striking side of the clock was permanently synchronized to the going (timekeeping) side. Thus, even if the hands are turned round inadvertently, without allowing the clock to strike certain hours, on the next hour it will still strike correctly. However, it must not be taken beyond 12 o'clock without letting it strike, otherwise permanent damage may ensue.
    Because it is essential that a clock with rack strike must always strike 12, both weights of the clock should be wound up together so that there is always sufficient power for it to strike.
    It is not possible to have a clock with rack strike going with no strike because of potential damage to the striking mechanism. The only exception to this is if there is strike/silent regulation on the clock or the movement is modified.

Count Wheel (or Locking Plate) Strike
    "Count Wheel" is probably the more correct term for this form of strike. It is the earliest way of controlling the strike on longcase and indeed all clocks and was employed on most London clocks made before circa 1700, most country clocks prior to 1720, and virtually all 30-hour clocks.
    With eight-day clocks it gives the advantage that if you do not want it to strike all you have to do is not wind the weight on the striking side (normally the one on the left as you look at the clock). No harm will come to the striking mechanism— as would be the case with rack strike. However, the strike will have to be resynchronized with the hands when the striking mechanism is put back into operation.

Correction of the Count Wheel
    To adjust the strike, the hooked bar (detent) which engages the locking plate is lifted and then released when the clock will strike the next hour (Figure 6). This process will have to be repeated until the strike is correct (for example, if the clock strikes two when the clock reads 5:00, then the bar will have to be lifted three times to set the strike correctly).

Position of the Count Wheel
    On all 30-hour clocks and most eight-day clocks made before 1690, the Count Wheel is mounted on the back of the movement. (Figure 7). With eight-day clocks after 1690, it is usually mounted inside the movement either in front of or behind the great wheel on the striking side of the clock (the left side as you look at it).

Winding: Thirty-Hour Clocks
    The term "30-hour clock" does not necessarily mean that it will go for 30 hours, but merely more than 24. Some may go for 36 hours, whereas others will stop if you do not wind them within 26 hours. Occasionally, an early singlehanded longcase clock will be encountered which requires winding twice a day, as did the first of the lantern clocks. The chain or rope which has to be pulled down to raise the weight is usually that on the right of the clock. However, to ease the strain on the movement, the left hand should be used to partially lift the weight, either by holding the weight itself or by raising the left-hand rope (Figure 8).

Eight-Day Clocks
    It is essential that the trunk door is opened before winding so that one can see that the gut lines are not twisted, that the lines are on the pulley, and that the weight rises smoothly and is not wound up too far. If it is then the pulley will hit the seatboard on which the movement rests, resulting in either 1) the pulley tilting and the gut line coming off; 2) the line breaking and the weight crashing to the bottom of the case; or 3) teeth being bent or broken on the great wheel.
    On all eight-day longcase clocks with rack strike, which probably comprises 95 percent of all those made, both the striking (left side) when looking at the clock and going weight (right side) must always be fully wound, otherwise the striking mechanism may be damaged. Ideally, the striking weight should always be wound a little higher than the going weight.

Figure 7.

Figure 8.

Calendar Work
    If the clock has either a hand or an aperture with a revolving disc or ring behind it which indicates the day of the month, this will need to be set correctly when the clock is installed. It will also require advancing by one day on the four months of the year when there are only 30 days in the month and by three days every February (except on leap years, when it will be only two).
    Some date indicators, usually the disc type, are driven from a part of the clock connected to the hour hand. These change every 12 hours, whereas others, usually the rings, are moved on by a pin on a separate wheel geared to turn it every 24 hours. The pin or lever which changes the date is usually only engaged for three-to-four hours a day so that only one number stays in the center of the aperture for practically the whole day. The date should be corrected when the mechanism is not engaged.
    The clock should have been set up by the clockmaker so that the date starts changing at or a little before midnight. By 4 o'clock the mechanism is disengaged and from then until 8 or 9 o'clock it is safe to move it.
    With a clock with a ring which moves only once every 24 hours, it may be necessary to turn the hand round 12 hours so as to get the date to change at 12 midnight instead of 12 noon. Once this is set correctly, the date can be altered at any time between 5 A.M. and 8 P.M.
    To actually correct the date, all that needs to be done (if it is indicated by the hand) is to open the hood door and move the hand to the correct position. With a date aperture it is usually necessary to remove the hood to gain access to the date ring or disc behind the dial before it can be rotated.
    Unfortunately, although all date mechanisms should be set up to commence changing at midnight and thus be free by 4 or S A.M., this is by no means always the case. Thus, if more than slight resistance is felt in moving the disc or ring it will mean that the disc is engaged and you must then delay changing the date until it is free. By looking behind the dial, you can often see whether or not the pin or lever driving the date mechanism is actually engaged.

Moon Discs

When a clock has a moon disc (which is usually situated in the arch of the dial), this also will need to be set correctly. This is simply done by removing the hood and rotating the disc in a clockwise direction (never counterclockwise) until the correct age of the moon is shown. As with the date ring the moon is moved roughly once every 24 hours; (it goes round 29 ~ times a month) and is only engaged for a few hours of that period. It is important not to try and move the moon disc when resistance can be felt because the mechanism will actually be turning the disc. On no account should you try to rotate the moon disc without removing the hood (for example, by pushing it from the front), as either the disc is likely to become distorted or the pin on which it rotates will be bent and the mechanism will then fail to work.

Summary

1. Make certain the clock is stable. Fix it to the wall if possible.

2. Always wind up both weights of the clock.

3. Never turn the hands backwards.

4. Always let it strike each hour.

5. To slow it down, lower the bob. To make it go faster, raise the bob.

6. Only correct the date between 4 and 8 o'clock.

7. Always open the trunk door before winding up the weights to insure that the lines are not twisted.

8. Stop winding weights well before the pulleys touch the underside of the clock.

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