Clock repair blog

CUCKOO CLOCK SUSPENSIONS

Most cuckoo clocks do not have suspension springs. They depend on
gravity and the power in the gear train to make the pendulum move. They do ,
however gave a suspension. It consists of 2 loops and one hook. The hook is on the
end of the suspension rod. Always check this system. The loops get grooves worn
in them and this is enough to stop the clock.Also check the top loop on the
suspension post to be sure they are not loose. The clock will stop if either one of these are loose. They must be tight, absolutely tight. If the post is threaded in the
threads can be tightened by closing the hole in the plate slightly with a hale closing
punch. This will adequately tighten the suspension , providing the hole is not closed
too tightly.
These loops in my opinion are best served by light oiling. Light meaning very
small amounts of oil , and a very light weight oil. Only enough oil to cover the friction
points with a thin film of oil should be used.

PROBLEMS WITH EUROPEAN MECHANISMS

The strike lift liver that is lifted by the star wheel quite often will get a
groove
worn in it if the edges of the star wheel are the least bit rough. The resulting common
complaint is that the strike doesn’t work all the time. The edges of the star wheel must
be polished or the problem will come back in a year or two.
In the mid-seventies there were some popular European mechanisms
made that had the 3rd wheel
time out of round. If you are in the repair business, you very likely will run into one
of these at some point in time. They will bind up intermittently , or will just stop and
loose power, If you are working on a popular European mechanism and have this problem ,
check the center wheel. Remove the clutch spring and spin the wheel on the shaft ; if
it is out of round it may have to be replaced.
The gear ratio in the popular European mechanism movements has had some problems
over the years. Once in a while there will appear a clock with a popular European mechanism
movement that just does not keep time. The problem is usually in the #3 and #4 wheels.
There were some 34cm wheels that got mixed up with 55 cm pinions. The way they changed the
pendulum length was to change the gears. the plates were designed to allow changing
of gear ratios without changing the position of the pivot holes.
Whenever you are working on a popular European mechanism, be sure to check the
tightness of
the click rivets while the mechanism is apart. it is much easier to tighten them up
when they are apart that when they are together.Check the ratchet wheels. If they
are chrome colored they are probably stamped, and have relatively poor teeth
.Replace them if possible . The newer ratchet wheels have milled teeth.
If a mainspring lets go , check the arbor where it locks in with the arbor
sleeve . The groove in the arbor will often have a slightly bulged spot where the
tab inside the arbor sleeve gouged it at the impact of the spring letting go. The
arbor may act as if it is stuck in the arbor sleeve (for no obvious reason) It very will
may be this little bulge that is holding it. Usually this bulge can be filed off and the arbor will still function . Over the years popular European mechanism has had trouble with set mainsprings.
If there is a problem with slow chime , and it seems as though all possibilities have been
considered, try replacing the mainspring.
THE HERMLE 3351-851SSK
This mechanism is very similar to the generic popular European mechanism , except

that it strikes
on the quarters and does not play the westminster tune:1 at quarter after , 2 at half
past, 3 at quarter to the hour; and 4 on the hour then counts the hour. The quarter
hour gear train has a different gear system than the standard chime train. The fan is
a chime blade with a strike pinion gear (7 leaf pinion). The number 5 wheel uses a
strike brass gear mounted on a chime pinion shaft (8 leaf pinion). Be aware of this
difference or there will be much trouble for you if you try to change the wheels in
the chime train.
Sometimes the popular European mechanisms have a problem with jamming up on the
lift i.e. ; on the
quarter hour. This can be caused by any number of things; one of the most common is
that the chime is releasing too soon and the warning pin on the warning wheel gets stuck
on the edge of the warning lever. This will stop the clock and of course will cause the
chime and the strike to stop operating. One way to correct this is to carefully bend the
strike trip/lock lever down in the middle( above the centerpost trip cam) so it rests
higher approx. .050 in. allowing more lift before release , which allows the warning
lever face to be up in position far enough to catch the warning pin without getting
stuck on the edge of the pin. Also check the stop pin on the chime shutoff cam to
be sure its angle is at least 90 degrees to the shutoff working face. These two
surfaces should not bind up on each other ; and will if the angle is over 90 degrees .
If it is under 90 degrees the lever will slip off the pin face too soon and the clock
will jam up no matter how much lift the lever has before the gear train releases.

VIENNA REGULATORS:

These clocks are definitely not user friendly. They are incredibly sensitive;
hardly have any swing (1in. is normal) and will not run if they are even slightly out of
beat. The
beat is next to impossible to set ; the cables will always tangle, and the cases usually are
falling apart. They are beautiful clocks , however , and once set up by someone who
knows how , they will run just fine and keep good time.
The verge will have worn pallet faces quite often. there are several ways to deal
with this. Some times it will be possible to offset the escape wheel so that the teeth are
working on the part of the pallet face that hasn’t worn yet. do this by bushing both
sides of the wheel and offset the bushings slightly. If this has already been done, and
the pallet faces are worn in both places ; the pallet faces can be turned upside down
and reversed if they are held in place by screws. If it is a solid one piece verge , it will
be necessary to make a new one or fill in the worn spots. I have done this with silver
solder. This is the least desirable way to get the job done. Perhaps a better way is to
file down the verge faces past the wear point , being absolutely certain to maintain the
same angle in the faces , then using silver solder , attach new hard steel faces with a
thickness that will give the net result of being the same distance between faces as
before the wear took place. Either way will work, providing all the flux is removed
when the job is done. Be sure to polish the pallet faces when you are done. Check to
be sure that the verge is tight on the shaft. Sometimes the impulse arm will be threaded
on at the top ; and if it is , there is a good chance that it will be soldered. I have seen this many times. I remove the solder and tighten it up by threading it back on until it
is secure (tight enough to hold it in beat , but loose enough to keep from bending the
escape wheel teeth if the pendulum is swung too far. ) If solder is found on the verge
clutch like this ; be prepared to find some bent escape wheel teeth.
The impulse pin on the bottom of the impulse arm usually has a threaded
adjustment system on it. Always check that pin , there is a good chance it will be loose.
The clock will not run if that pin is loose , even slightly loose. Disassemble that
adjustment system , if need be, and tighten that pin ; it will save hours of frustration.
Many of the Vienna regulators have slightly tapered pivots; leave them that
way; and if you rebush , make sure the hole in the new bushing is tapered to match.
Most of these are very precision mechanisms they aren’t very forgiving. The pivots
are for the most part very hard steel and will break very easily.
Check to see if there is a cable/pulley stop on the bottom of the mechanism.
If there is , make sure the pulleys wind into them properly before you re-install the
mechanism. When the mechanism is apart , be sure to check the cables inside the drums
to be sure there are no bad ends there. Check the pendulum clearance with the weights
even with the pendulum bob, set the beat and let the clock run for a while to be sure
the weights and pendulum and gong will clear each other. Be sure to check the
pulleys to determine if they are worn . They must be rebushed if they are worn.The
mechanism in a Vienna regulator can’t be leaning forward or the cable will jump off
the main wheel drum.

CHELSEA CLOCKS , ASSEMBLY INSTRUCTIONS:

The centerpost on some Chelsea ships bell clocks comes apart at the center.
It only goes on one way ; it will be crooked if it is put on 180 degrees off. Set the time
gear train up first and fasten the middle plate. Then set up the strike. Keep in mind
that the mainspring barrels are reversed ; so be sure to make a note somewhere as
to which way the mainsprings hook. The self correcting and the hour vs half hour
levers should not have to be filed or otherwise bent unless someone has altered
them. Chelsea clocks are very well made and do not need excessive adjustments
unless tampered with. If it is necessary to rebush a Chelsea ships clock , be sure
to support the bushing from the bottom as you may inadvertently push it out in
the process of installing a new bushing.
DUTCH CLOCKS:

If you are going to work on dutch clocks it will be particularly helpful to
have a place to hang them where it will be easy to access the suspension and the
impulse arm as these clocks can be very difficult to put in beat. The chain retainers
that prevent the chains from slipping inside the case are usually an the weight The

hands are very thick and the hub in the minute hand usually will not slip:
so if the centerpost strike strike trip cam has been removed; be absolutely
certain to check the trip position before the cam is driven back on the centerpost. If this is
not checked there will be a major problem in that the minute hand trip position
will be off at the final stage of the repair; and you will have to either destroy the
minute hand or partially disassemble the thing just to get the minute hand to line
up at the hour and half-hour trip. Be aware that there are 1 day and 8 day models.
If the chain does not fit correctly IE: if the links are too large , the chain may climb
up on the sprocket teeth. The side that has no weight will not be able to hold the
chain tight and this will allow for the chain to climb the sprocket teeth which will
result in the clock stopping mysteriously occasionally. When the chain and
mechanism are mounted in the case , it is almost impossible to see whether or
not the chain is bound up. When the clock is moved to inspect the mechanism ,
the chain slips back down to the correct position before you can see it and the
clock will run fine when it is hung back up on the wall. You will never know that
the chain bound up , or exactly why the clock stopped.

QUAIL CUCKOO CLOCKS:

Quail cuckoos are quite involved and can be very challenging repair items. They
contain of course 3 bellows and usually have the strike controlled by count wheels. The
quail gear train usually trips the cuckoo train.The quail is tripped at the quarter hrs.
Once at quarter after , twice at half past, three times at quarter to the hour , and four
times at the hour and then the cuckoo is released and and allowed to count the hour.
Always check for worn pinions on these clocks . They will have to be replaced
if they are worn., That is it ; the clock will not work dependably if they are not fixed.
Also check for worn ratchets; this is a common problem on the older cuckoos.
The shutoff cams in the quail and cuckoo gear trains can be quite difficult to
set. They must be set st they they don’t lift the shutoff lever too high to cause it to
jump over the stop pin, but enough so that they still shut off. Do not try to bend the
shutoff lever too far; it is usually very hard brass and will break quite easily.
The brass in the plates of these clocks is usually very high quality (IE: very
hard and wears well ) so only rebush them with bronze bushings and if the bushing
has marginal wear ; it is best to leave it just a tiny bit on the loose side. Be very  cautious of the bushings that are near to the edge of the plate ; the edge of the plate
is very easily broken if a bushing of too large a diameter is used. If you are not sure ;
use the smallest bushing that can be drilled out to fit the pivot. It would be well to
check for this type of situation before toy get too far into the repair job.
The count wheel is critical to the proper operation or the bird action. The
shutoff lever must bot be allowed to bounce at all, or the bird will flop in and out
of the little door. The lever must ride solidly on the count wheel without making it
bind. Be sure the count wheel is mounted securely. The looser the count wheel the
QUAIL CUCKOO CLOCKS:

more chance of failure. Do not, however, make the count wheel so that it puts even
the slightest undue pressure on the gear train’s ability to move.
The hands on these old cuckoos are brittle and will break very easily. It is
best to look for cracks or places where the hands have been glued before you even
start the repair. Many of the hands on these old clocks are made of ivory and are
impossible to replace. Warn the owner of this ahead of time if it is practical.

GOLDEN HOUR:

The golden hour clock is the only series in the Jefferson electric that
motors are available for now. When the motor is replaced, the dial glass and gear
and gear ring and housing should be cleaned. Some information indicates no oil should
be used on the dial gear ring and housing, and some says oil is ok. My experience
has taught me that if much more than a very thin film of oil is applied problems
will occur.  The motor should be mounted so as to leave some play in the gears ,
but not too much. Bring the gears together as closely as possible and then separate
them by about .020 in. plus or minus .004 in.. Do not allow too much play in the gears
because they will lock up when the teeth hit on the gear tooth ends. Do not ,on the
other hand, allow the gear teeth to bottom out on each other .
Be sure to check the cord when the motor is replaced. If the cord is bad ,
replace it. Pay particular attention to the plug and the strain relief insulator at the
back of the case; these are the most common areas of problems.

TELECHRON:
This is a type of electric clock that works on 110 volt 60 cycle electric
current. There are quite a number of different types of Telechron electric clocks
but only a few will be discussed here. The 2 most common problems with the
telechrons are the rotors (including the coil) and the actual mechanical part of the
clock. It has been my experience that if the coil is bad, it is usually because of a
power surge , improper handling , or just plain age.
The rotors that have a flat side on the shaft are usually the same as far
as the gear ratio and external size as those
that have a round shaft. Check the rpm rating , the size , the direction of rotation ,
and the diameter of to shaft. If the only difference is the flat side on the shaft then
either one will work. Of course you must file a flat side if all you can get is one with
a round shaft. Always check the power cord if it is worn anywhere replace it.
Be very careful where the cord enters the coil it will break very easily.
When the sequence is set , be sure that the trip pins on the centerpost are at
the hour position. If this is not done , the chime and strike will not release at the
correct time and the gear train will bind up or the tempo of the chime-vs-strike It is normal for the coil to heat up slightly ; it should not get too hot to
touch ; if it does , something is wrong. More than likely the coil is shorted. This can
be a fire hazard so be careful and be sure to check them out carefully. Some
alternating current hum is normal however it shouldn’t be too noticeable. Sometimes the
rotors are noisy ; it is gear noise that causes this. Don’t confuse this with hum.
Sometimes there will be both hum and gear noise. Replacement rotors can usually be ordered
from most clock repair supply houses. These rotors are becoming much harder to find.
As of the writing of this journal some of them are no longer available. The old rotors
were made of copper and were soldered together. They can be taken apart and repaired.
Inside the capsule is a tiny ac induction motor that powers a reduction gear train.
They are oil filled so I would not recommend opening them using any kind of heat.
I have cut them open by chucking them up in a lathe and CAREFULLY cutting a groove
in the top part of the capsule. If you look closely you can see where they have been
soldered at the factory. The newer rotors can be cut open also. They are made of aluminum.
The gears inside are plastic and so are some of the bushings.