|DIRECTIONS FOR ASSEMBLING
POWER WOUND WEIGHT DRIVEN TOWER CLOCKS
|CONNECTING UP MOVEMENT
TO DIALS AND BELL
|THE GRAVITY ESCAPEMENT
|TO SET GLASS DIALS
|TO PUT NUMERALS ON WOOD
OR GALVANIZED IRON DIALS
|ELECTRIC RELEASE MOVEMENTS
|TOWER CLOCK ATTACHMENTS
|AUTOMATIC SILENCING DEVICES
|HAND SILENCING DEVICES
DIRECTIONS FOR ASSEMBLING
* * *
POWER WOUND WEIGHT DRIVEN TOWER CLOCKS
Power wound weight driven tower
clocks are constructed with all weights, pulleys, motors, gearing and
control switches built into them as a unit, the only parts not in the
movement being the shafting to the dials, the dials and hands and the
hammer for striking the bell with actuating chain.
The weight (or weights, depending
upon whether the movement is for time only, time and strike or time,
strike and chime) consists of several cast iron leaves bolted together,
with pulleys at top and bottom.
There are also several loose
or adjusting weights. Each weight is suspended by an endless chain
which passes under the top pulley and hangs from two sprockets, one on
the weight arbor of the train and the other on the winding-device speed
The winding device lifts the weight
when it reaches its lowest point of travel by drawing up the chain on
the side which runs over its sprocket; at the same time the chain over
the weight sprocket is held taut and is not raised. Thus the weight is
raised without affecting the driving force on the clock train. The
control switches, mounted in approved metal boxes on the floor plate at
the back of the clock are tripped by the weight when it reaches the end
of its downward or upward travel. This will be explained in detail
Where the construction of the tower
permits locate the movement near the center of the tower, also have the
connections from hammer lever on the clock to the hammer on bell as
straight and direct as possible. Often owing to the interferences in
the tower it is necessary to locate the movement in an out of way place.
In such cases our engineers should be informed so that they can
furnish blueprints showing a recommended installation.
It is not necessary to locate the
movement exactly at first as it can be put together and moved after
complete assembly. With striking clocks, it is best to put in the rack,
snail, rack detent and the small parts that go inside of the bed before
the main wheels are placed. These parts must be handled carefully as
they govern the striking of the clock and must not be bent. On the No.
15 striking clock the rack and rack detent are in one piece.
All parts, and especially the
bushings and bearings should be cleaned thoroughly before being put together,
and all bearings and parts that rub should be oiled with the tower clock
sent with shipment.
To assemble the clock first place
the floor plate in the desired position in the tower. Screw the
supporting pillars into the floor plate. Mount the bed on the pillars
and put on the pillar nuts. Next, bolt the back top frame in place.
The back top frame is the one without the second dial.
The arbors are so arranged that they
can be put on after the bed is in place and the top frames bolted on.
The time arbors are shipped with parts assembled complete. The fly
arbor has the fly detent on the front end, and the fly ratchet and fans
on the back end. Note: The fly ratchet and fan can not be put on until
the fly arbor is in position. Insert the back pivots of arbors into
their respective bushings in back of frame and then put front top frame
Next put on the top girt (or plate).
The pallet and escape arbors should not be put in the clock until the
top girt is in place. The escape arbor may be put in by removing the
second dial from the front top frame and slipping the escape arbor
through the hole from the back of the frame and then replacing the
seconds dial. The pallet arbor, with pallets in place, should be put
through the hole in the front top frame, the crutch wire slipped onto
the arbor and the arbor placed in the hole in the pallet plate. The
back pivot of the pallet arbor is carried in the sliding socket. Do not
let the pallets come in contact with the escape wheel until the
pendulum rod is in place.
The pendulum spring and fork should
be put into the top girt and the washers and adjusting knob put on; the
safety hangars and chops should next be put in place, and the pendulum
To hang the pendulum, first put the cup
on the rod from the bottom, and then slide the rod down through the
ball and put on the nut. The nut at the bottom of the pendulum rod
should be screwed up until the bottom edge of the nut is even with a
scratch mark on the surface near the bottom of the pendulum rod. This
will bring the top of the pendulum ball even with a pencil mark on the
wood rod. (The cup or ornament on top of the ball must be raised to see
this mark.) This will locate the ball in a position where the final
adjustment can be made by the knob at the top of the pendulum fork, and
when final regulation is made the pendulum pin will swing clear of the
safety hangars. Wind the time weight by hand for a try-out, then add
sufficient leaves to the time weight to give the pendulum the right
If the clock is fitted with a
Gravity Escapement the amount of weight does not affect the motion of
the pendulum, but the weight should be sufficient to give the clock a
prompt motion on the escape wheel and be able to drive the external
The bed of the clock must
be made to stand perfectly level to have the pendulum in beat; the
clock is adjusted at the factory and will be correct if not changed
before being put into place.
Should the floor of the clock room
settle at any time, causing the clock to be out of beat, see that all
screws about the escapement are tight, then put the clock in beat by
turning the two knurled screws located near the top of the crutch piece,
turning to right or left as necessary until the pallets are equally in
beat on each side of the escape wheel and tighten both thumb screws
against the crutch piece.
The lockwork levers are used to
control the striking of the clock and are fastened to the bed by means
of the lockwork stand. This stand is bolted to the left end of the bed.
The end of the long lever rests on the lift cam on the minute arbor
and when lifted by the cam raises the short lockwork lever, which
controls the rack.
To set the strike train of the
clock, turn the main strike wheel until the hammertail lever has just
dropped off one of the cams on the wheel. Hold the strike train in this
position and set the detent lever on the fly arbor so the projection on
same rests against the projection on the lockwork lever, and fasten
detent tightly on the fly arbor. With the train still held in this
position, set the pickup, or gathering pins, on the second strike wheel
arbor, so that one of the pins will have picked up a tooth in the rack
and have passed far enough ahead to allow the rack to pass under it when
the lockwork lever is raised to strike the next hour.
To set the clock to strike the
correct hour in relation to the hands: Set the minute arbor on the time
train so the lockwork lever just drops off the point of the lift cam,
and with the minute arbor held in this position set both hands on the
setting dial at 12 o'clock and the the hand on the seconds dial at 60;
with the minute arbor still held in this position, loosen the snail bind
knob so the snail will come out of mesh with the small pinion on the
minute arbor, and set the snail so the rack detent pin will rest in the
center of the lowest step of the snail; set the snail wheel back in mesh
with the pinion and fasten with hand knob. Be sure snail bind knob is
set up tight.
When the strike has once been set correctly
in relation to the time train it is impossible for it to change its
Weight rests are furnished with all
power wind movements. These should be placed on the floor inside the
floor frame and the weight assembled on top of them. When assembling
the weights see that all oil holes are up. These oil holes extend
through the projection on the weights through the pulley stud and
deliver the oil at the center of the pulley stud at the bottom side of
The chain should be passed over the
smaller sprocket on the winding device gear box, under the upper pulley
on the weight, over the larger or driving sprocket on the weight arbor,
under one pulley on the adjusting lever, over the pulley on the bottom
of the weight, under the other pulley on the adjusting lever and brought
around so that the ends of the chain meet. These ends are connected
with a special connecting link furnished with the chain.
After the chain is connected and any
kinks removed, the adjusting lever should be lowered to take up the
slack, and clamped tight at each end. Chain should be fairly slack, as
too much tension will add to the load and may stop the clock.
The control switches operate by
means of a brass rod extending upward from the switch handles through a
hole in a square stud in each weight. Two brass collars with set screws
slip over each brass rod. The positions of these collars on the rod
should be adjusted to throw the switch in or out to the best advantage
at the bottom and at the top of the weight travel. Small springs are
furnished to be placed over the rod between the brass collars and the
square stud. The upper spring takes up the additional travel of the
weight after the current is shut off; the lower spring gives a slight
additional fall to the weight in case the power should be off the
instant the switch is thrown in. It also protects the switch handle
from too great a strain.
Care should be exercised in setting
the collars on the switch rod so that the switch throws in just an
instant before the weight settles on the weight rests. Erect the clock
and thoroughly test out the switch to be sure that it operates correctly
before connecting power to the motors. Also make sure that motors are
wired up to run the proper direction.
Standard motors of fractional
horsepower are used. Be sure that the current supply agrees with the
data as given on the motor plate, particularly as to voltage and type of
current. Automatic overload cut-outs are provided for each motor, and
should be wired into the circuit. It is preferred that the clock motors
be connected to a circuit not used for any other purpose, as there is
less chance of someone throwing out the switch.
Should the strike weight be allowed
to run down, or the clock stops striking for any reason, it is not
necessary to "strike the clock around," as with the ordinary house
clock. Simply raise the rack up to the highest point, wind the weight
and the clock will strike correctly at the next hour, provided of course
that the time train has not been interrupted.
CONNECTING UP MOVEMENT TO DIALS AND BELL
The clock must be so positioned
that the center gear is set in the center of the
in line with the centers of the dials and if the distance from the
clock is short, gaspipe may be used for the leading-off rod connection,
but if the distance is very much, tin tube must be
If the distance is more than 15 feet, an intermediate bearing should be
used with a set of universal joint couplings between each connection,
the sliding part of the coupling to be set at the bottom. The
connections considered correct for use will be sent.
To set the dial gearing in glass
dials, loosen the set screws in the yoke and remove the shafts from the
sleeve, remove the large nut from the sleeve and put on one of the metal
plates sent and a rubber washer; place in dial from the outside and put
on a rubber washer and a metal plate and tighten in place with large
nut; the oil holes must be at the top. Care should be taken not to
break the glass. Assemble the dial-works, making sure to leave a little
end-shake in the shafts to allow them to run freely.
To set the dial gearing (motion works) in wood dials:
The motion works are designed for dials 1 3/4
thick and must be used with dials of that thickness.
If the dials are less than 1 3/4
thick, wood cleats should be put on the back of the dial where the
motion works are placed to bring them up to thickness. If the dials are
more than 1 3/4
" thick they must be
chiseled out to the correct thickness. The surface where the motion
works go should be parallel with the outer face of the dial. Set the
motion works with the oil holes up.
In setting the coupling on the dial
connections the set screw on the two inner ends of the coupling should
be placed in line, and the slide set hafway in the slot in which it
The conduit (tin tube) can be easily
measured by placing one brass hub in the coupling on the dial gearing
and one in the coupling on the center gearig and marking where the tubes
come together; enough tube should lap over to make a strong joint when
Setting the hammer: If the bell is
in ringing mountings (i.e., is swung by a wheel and rope) the hammer
should be set on the opposite side of the bell from the wheel and should
strike through the bell frame. The hammer should be set to strike the
bell on the sound bow (or thickest part of the bell) and be securely lag
screwed to the floor or platform to withstand the vibration of the
hammer on the buffer spring.
The buffer spring can be adjusted by
nuts on the studs at the front and the back of the shoe, and the spring
should be set to keep the hammer from striking a blow on the rebound
after each blow by the clock.
As the leather pad on the buffer
spring will harden and compress after a little use it will be necessary
to adjust the spring, but after the leather has once settled into place
it will not change enough to do any harm. If possible the hammer should
be connected to the hammer lever on the clock on a straight line, but
if this is not possible the chain guide pulleys can be used. Place one
pulley directly over and in line with the clevis on the hammer tail
lever on the clock and one pulley directly under and in line with the
loop on the hammer lever. The pulleys must also be in line with each
The galvanized chain should be used
to operate on these pulleys and the linked wire is to finish the connections.
on the pulleys should be set to keep the chain from jumping out of the
groove of the pulley when the clock strikes, and should not rub when the
chain is under tension.
Care must be taken to have the chain
and the pulleys perfectly in line to avoid any unnecessary friction.
THE GRAVITY ESCAPEMENT
The general arrangement can be seen
from cuts in the catalogue, the escape wheel, fan and arbor are packed
together and are assembled ready to put in the clock. The gravity arms
should be hung on the short arbors from the bearings in the top girt and
front top frame, the studs at the bottom of the arms should point out.
The pendulum furnished with this
escapement is made to have zero coefficient of expansion, hence is not
affected by temperature changes.
TO SET GLASS DIALS
Plumb through the center of the dial
opening and mark at the bottom of the opening and set the section with
the VI directly over this mark. Fasten this section so it will be safe
and put the next section on, and then install the section on the
opposite side, etc. The XII section is to be set last, then bolt all
sections securely, being careful not to "bulge" the dial frame. Plumb
from the 12 o'clock through the center to the VI and fasten the dial to
the building with the fasteners sent when it is plumb.
If there is more than one dial,
all the frames should be set before setting the glass.
Each piece of glass is marked and
should be placed according to these marks, as the glass is very
irregular in shape and will fit only the section for which it is marked.
Set all outside sections of the glass first,
using good putty or
cement. It is more convenient to set the bottom glass of each section
first and fasten it in place with the brass angles. If it is impossible
to get outside to place the hands, one section of glass may be left out
until the hands are set.
In placing the center glass care
must be taken not to force or cramp it as it will break from the effects
of the cold if set too tight. If there are four dials to be set, it is
best to set the glass on opposite dials, viz: first set the north dial
and next the south dial, this reduces the wind pressure on the glass.
If the dials are in whole plate the
hands may be set before putting the dial in place. Set the dial gearing
as instructed, and put on the hands, set both hands to point to the
(XII) and then set the dial in good putty and plumb through the XII and VI.
TO PUT NUMERALS ON WOOD OR
GALVANIZED IRON DIALS
Strike a circle a distance from the
outer visible edge of the dial to twice the diameter of the minute dots,
to be divided into 60 spaces for the minute dots and another circle (4)
times the diameter of the minute dots away from the outer edge of the
dial to locate the inner edge of the numerals. Before spacing these
circles, plumb through the center of the dial to locate the XII and VI
and dividing from these points locate the minute marks.
The diamonds are to be used at the
five minute marks and the ends of the diamonds nailed with brass nails
to keep them from turning.
Round-headed brass screws should be
used for both numerals and dots and holes should be bored for them
before screwing in place; this is especially needed on dials covered
with galvanized iron.
When attaching the dialworks to the
back of wood dials see that the surface they are fastened to is flat and
parallel with the face of the dial. Test this by putting on one of the
hands and swinging it around the dial noting that the distance from the
point of the hand to the surface of the dial is the same all around the
dial, also see that the dialwork's minute arbor and hour hand pipe
project through so that the hour hand, when placed in position, clears
the dial and the numerals.
When standard wood or galvanized
dials are furnished by the factory the numerals and the minute marks are
all assembled to the dial plates.
Should the clock strike too slowly,
first see that all bearings of the strike train, hammer connections and
weight pulleys are free and thoroughly oiled; if the strike is still
slow, either set the fans to give less resistance, or add more weight.
Should the leather pad on the hammer
spring become compressed so as to allow the hammer to strike the bell a
second blow when rebounding, raise the hammer spring by adjusting the
nuts on the upright studs in the hammer stand until the hammer clears
the bell on the rebound.
Should the clock stop at any time,
and it is a striking clock, see if the detent arm on the fly arbor is
caught on the releasing lever so the lift cam on the minute arbor cannot
raise it; if so, and the strike weight is not run down, it indicates
that the strike train failed to start positively when the releasing
lever fell; and all parts pertaining to the strike mechanism should be
inspected to see that the bearings are not gummed or dry.
If the strike train is clear when
the clock is stopped, look for the obstruction in the time parts; if the
gears between the minute arbor and the escapement are under tension and
the connections to the dials are free, the trouble is in the movement.
See that all bearings of the time parts are oiled and free--that no
dirt or other obstructions have lodged in the teeth of the wheels or the
leaves of the pinions, and that the escapement is in beat.
If the gears connecting to the
escapement are free, and the connections to the dials are under tension,
look for the trouble at the motion works or hands, and if these are
found free, follow backwards toward the movement--testing each part in
order until the trouble is located.
If, through any cause, the hands on
the outer dials should not correspond with the hands on the small
(setting) dial, or with the striking of the clock, stop the clock with
the lift cam on the minute arbor in position to just allow the
strike releasing lever to fall; then loosen the set screw which secures
the couplings to the upright shaft on the movement, and turn the
coupling forward or backward to bring the minute hand to the figure 12
(or XII), and the hour hand at the proper hour, and tighten the set
screw again. With the hands all running alike, further change can be
made if necessary by a setting device on the minute arbor which is
turned with a key sent--each full turn of the key moving all
hands--inside and outside, and also the the lift cam and snail wheel,
one full minute.
The smaller size clocks, Nos. 4 and
14, not having this setting device, must be set by holding the escape
wheel, loosening the set screw at the top of the pallets, sliding the
pallets back and clear of the escape wheel, then letting the movement
run until the desired time is indicated„always keeping control of the
movement by pressure on the escape wheel
and being sure the escape wheel is stopped before sliding the pallets
back in position. Let the movement run past the correct time
sufficiently to allow ample time to get the pallets back in place, and
the set screw firmly seated before starting the clock.
With the gravity escapement special
care should be taken that the gravity arms are not bent while unpacking
or handling them. The lifting pins at the center of the gravity escape
wheel and the steel stops on the gravity arms should be oiled; but the
rollers that bear against the pendulum rod should be kept clean and dry,
as anything here that tends to make the rollers adhere to the pendulum
rod when the arms are lifted by the escape wheel, will disturb the
time-keeping qualities of the clock.
The clock may be set forward by swinging
the gravity arms to each side to allow the escape wheel to run
Oil all bearings on the movement with a synthetic oil
about once in two months, or often enough to keep the oil
Put a little oil on the pallets of the escapement weekly.
The journals, or bearings, should be oiled at the
outer end and at the inner shoulder, to be sure it will reach the full
length of the bearings.
The motion works should also be
The pulleys, hammer work and the
on the strike wheel with a good machine oil about once a month.
To regulate the time, adjust the
length of the pendulum by the knob at the top of the pendulum
suspension, turning it to lengthen the rod to make the clock run slower,
or turning it to shorten the rod to make the clock run faster. Before
making this adjustment, loosen the knurled screws at the sides of the
pendulum spring to slide between the bronze clamps, and afterward
tighten the screws to hold the clamps firmly against the suspension
spring. The ornamental nut at the bottom of the pendulum rod should
first be adjusted so that the bottom of the nut is just even with a
scratch mark on the brass piece at the bottom of the rod; then when the
clock is regulated for time, the pendulum will swing clear of the safety
Final adjustment may be made by
putting small weight (such as lead shot) in the cup at the top of the
pendulum ball, to make the clock run faster, or removing them to make it
ELECTRIC RELEASE MOVEMENTS
The electric release weight driven
tower clock movement is constructed in the same general manner as the
pendulum tower clock, but the time train is escaped once a minute or
twice a minute by magnets which receive their impulse from a master
clock. Cuts in the catalog show the escapement levers. Electric
release tower clocks are usually installed in connection with secondary
clock systems. They should be given the same care and attention as
pendulum clocks. On these movements, however, there is no setting
device; the usual method of setting the hands being to trip the magnet
armature by hand or by rapid impulses from the master clock.
SYNCHRONOUS MOTOR MOVEMENTS
The synchronous motor tower clock
consists of a motor having an absolutely constant speed, with a gear
reduction to bring the motor velocity down to that of a
Some motors run at 3600 RPM, others at 1800 RPM, and others at much
lower speeds. In every case, however, the motor speed depends upon
absolute constancy in the current frequency, and can only be depended
upon when the velocity of the power house prime mover is controlled by a
master time piece. In the usual parlance this is spoken of as a
"regulated power supply."
As the motor of a synchronous clock
must run continuously, any interruption of the current supply will stop
the clock. When the current returns the motor will start again, but the
clock will be
Synchronous clocks are used for sign work and small advertising
clocks, but have limited life and are not generally installed in public
buildings or where access is difficult.
TOWER CLOCK ATTACHMENTS
The automatic electric light switch
is one of the attachments used most often. This consists of an
arrangement for tripping on and off the electric lights which illuminate
the dials. It is usually mounted on the top girt, geared into a bevel
wheel on the upright shaft. Other locations for it are connected into
the line of shafting, geared into the yoke shaft on the back of the
movement; or mounted on a stand on the floor and drive by a downward
shaft from the clock.
Independent electric light switches
may be operated by a spring-wound clock movement or a synchronous motor.
A slight difference in the time between the switch movement and the
tower clock movement is of no importance in operating the lights.
AUTOMATIC SILENCING DEVICES
On striking clocks and chiming
clocks may be furnished devices for silencing the strike and chime to
conform to a certain schedule, which may be changed at the will of the
caretaker. A disk with 24 segments representing the hours of the day
and night permit the silencing over a variable period simply by setting
the segment outward. Care must be taken in installing the silencing
device to see that the time of the segments corresponds with that of the
pilot (setting) dial, and that the levers which hold up the rack and
lockwork levers are free to function properly. Be sure that all
segments are either all the way in or all the way out, otherwise the
clock may get out of correct striking.
HAND SILENCING DEVICES
Hand silencing devices are for
silencing the strike or chime manually when only required for short
periods, such as during church services, etc. Blue prints of these are
usually furnished to show method of installing.
1A "leaf" is a separate cast-iron square
or round part of the weight.
Back to text.
2 Mobil 1, SAE 5W30 or 10W30, is the current
oil of choice.
Back to text.
3 The cup is used to regulate
the clock. Various small weights, such as lead shot may be added (to
make the clock run faster) or removed (to slow the clock.)
Back to text.
4 In a gravity escapement
clock, the weight is used primarily to drive the external hands, and the
wheels, up through the escape wheel. The impulse to the pendulum comes
primarily from the arms which are lifted by the train, where in a
conventional clock, the weight has a definite effect on the impulse to
Back to text.
5 The reason for this is to
prevent an attempt to drive the outside dial hands with too-great angles
on the universal joints. A universal joint will jam and stop the
clock if the angle is excessive.
Back to text.
Modern usage accepts electrical conduit tubing, 3/4 to 1 inch external diameter.
Back to text.
7 When using conduit for
leading-off rods, it is recommended that new hubs be made up, or the old
ones turned down to fit. Pinning the hub to the conduit is recommended
Back to text.
8 The "guard" is nothing more
than a pin fitted across the groove of the pulley, placed there to keep
the wire rope or chain from jumping out of the groove.
Back to text.
9 Mastic cement is similar to
the cement used to place ceramic tiles on a bathroom wall. The primary
requirement is that it be waterproof, and capable of sealing the
glass/metal joint against the weather.
Back to text.
10 Needless to say, this can
be a dangerous procedure. Do NOT let the clock run away from you--it
may literally explode. Always keep one hand on the escape wheel arbor,
and let the clock advance slowly. Keep the pallets away from the escape
wheel--otherwise it will be damaged.
Back to text.
11 Once more, this can be a
dangerous procedure. Do NOT let the clock run away from you--it may
literally explode. Always keep one hand on the escape wheel arbor, and
let the clock advance slowly. Stop the escape wheel before releasing
the arms. Do NOT just drop the arms to stop the clock--something will
Back to text.
12 Mobil 1 synthetic oil (SAE
5W30 or 10W30, according to climate) is the current oil of choice. A
word of caution about oiling bushings: If any of the oil runs
out of the bushing, ALL the oil will follow it.
Wipe up the overflow, and re-oil the bushing.
Back to text.
13 It may be necessary to
remove a section of glass or to open the inspection port in a wood or
metal dial to oil the outer bearing in the hour pipe that carries the
minute arbor. The south and west dials are particularly prone to
needing frequent oiling.
Back to text.
14 A light grease on the cams
is preferred over oil.
Back to text.
15 Keep your fingers out of
and away from the gearing on these clocks. They cannot be stopped as
can a weight driven clock. An emergency electrical shut-off should be
placed within easy reach of the movement.
Back to text.
16 It has been found that a
voltage-sensing relay should be wired into the motor supply circuit.
If power is lost, the relay drops out, and must be manually reset within
the clock room. It has been noted that some of the synchronous motors
will start up backwards as they age.
Back to text.
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