Back to Notes From The Bench index

Clock Repair Archive - -     Quail cuckoo clocks:


	Quail cuckoos are quite involved and can be very challenging repair items. Have
a test rack set up to run and observe them on. Spend a siginficant amount of time
inspecting the mechanism before you take it apart. Check the bellows for tears or worn spots.
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 hour
(every 15 minutes). The quail sounds once at quarter after , twice at half past the hour ,
three times at quarter to the hour , and four times at the hour. Immediately after this
the cuckoo gear train 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. Some of these
clocks have hard steel in the pivots and pinions. Be careful ; they can break easily because
they are very brittle. 
	The shutoff cams in the quail and cuckoo gear trains can be quite difficult to
set. They must be set so that 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 you get too far into the repair job. 
	The count  wheel is critical to the proper operation of the bird action. The
shutoff lever where it rides on the surface of the count wheel
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 
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. This is very important. Check the clock when you first get it ; 
and do this in front of the customer. If you find a crack or a place where the
hand has been glued point it out tactfully to the customer and make a note of this 
condition on the repair order paper work that the customer signs. 
Many of the hands on these old clocks are made of ivory and are 
impossible to replace. If the hand is cracked or if you break it during the repair
you will have more trouble that you care to deal with. 

	Determining the correct type of chain:

	If you have a quail cuckoo clock that does not
have any chains or has chains that do not work correctly there is a way to determine
what chain to use. First ,count the number of teeth on the sprocket and measure
the effective diameter of the sprocket. Also, check to be sure the sprocket teeth are all
straight and uniformly spaced; significant amounts of wear or damage will prevent even a
chain of correct dimensions from functioning properly. Keep in mind that most cuckoo clocks
sprockets / chains use every other link , so the distance between sprocket teeth must
match the distance between 3 centers of links. Use the formula to find the circumference
of a circle; to find the distance around the sprocket exterior ; then divide that by the
number of teeth to determine the required distance between every other link ie: the
distance between sprocket tooth ends. The wire diameter must be such that the links will
set in the saddle of the sprocket enclosure without climbing out as the sprocket turns as
the clock is running or when the clock is being wound. Cuckoo clock chain is catagorized
by the number of links per foot and wire diameter, so it will be necessary to remember
that you will need to calculate the center to center distance between links before you
will know which chain will be the closest fit to your sprocket tooth pattern. Keep in 
mind that where the links hook together there are two thicknesses of wire diameter.
The links should sit approximately 50% of the way down on the tooth. The final test, 
however, is whether or not the chain pulls through without any places that bind up. The 
chain must run though SMOOTHLY or the clock will not work. If the links climb up on the 
sprocket teeth when the chain is pulled though, then the chain is not the correct link per 
foot count or the wire diameter is wrong.Many times the chain will climb up on the sprocket
teeth on the side opposite the weight (theloose end side). You will not see this if it is
up inside the clock. Sometimes the chain will climb only intermittantly. This is a very 
difficult thing to catch. It will happen when the customer has the clock at home. They 
take it off the wall , bring it back in to you and by the time you get it, the chain problem 
has vanished. You will hang the clock up and it will perform perfectly. I am not suggesting 
that you check each link on every chain on every cuckoo you repair. What I am saying is to 
check each chain by pulling it through the sprocket and watching it carefully. If you have 
a cuckoo come back and there appears to be nothing wrong , then you need to check the 
chain VERY carefully. This is also true for most chain drive clocks. Brass chain does 
stretch more than steel chain , but it tends to wear the sprocket teeth less. It is usually
easier to replace a chain than a sprocket.

	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 have 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 hole 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. 

	Most cuckoos have what is sometimes called an "Anchor escapement" system or a "Recoil
escapement". This type of system does not have a lock action , it is simply impact, slide ,
and release. The recoil escapement is less critical to adjust, and generally speaking ,
is more efficient in that it does not take as much power to run. However this type of
system is less accurate because the motion of the pendulum is less isolated from the 
gear train. The escape wheel tends to bounce backwards at each impulse ; and as the 
spring runs down the arc of the pend slows causing less bounce or recoil in a nonlinear
manner. In the case of weight drive cuckoos this is not as much of an issue.
The escape wheel/verge depth on this type of escapement in not as critical as
the dead beat escapement. On most cuckoo clocks the depth should be set so that the 
escape wheel is 80% of the way from completely missing ; to actually hitting on the
edge of the verge on both sides(binding up). Generally speaking, the lighter the
pendulum, the deeper the setting on this type of system, up to the 80% amount. 
If possible the escape wheel should move equally on each 
side of the tick. Often the verge has either been bent or replaced and the escape
wheel will impact,slide and release  further on one side than the other; and in many 
cases the clock will run. My experience has taught me that this is not an extremely 
critical adjustment on this type of verge with respect to whether or not the clock will 
run.If the goal is just to get it to run ; then don't be fussy. To charge a customer a 
premium price for this kind of work , however is quite another matter. The majority of
clocks (excluding cuckoos) that I have seen over the years have an even release distance
on the impact ,slide , and release. If you want to do accurate, original , restoration; 
then set both sides of the sequence equal.      

Back to Notes From The Bench index

Page by: Perpetual PC's
Copyright (c) 2002 David Tarsi. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with the Invariant Sections being no invariant sections, with the Front-Cover Texts being no Front-Cover Texts, and with the Back-Cover Texts being no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License".

The content of this website and journal has been prepared to provide information on the authors experience. The information is not a complete source. Use at your own risk. Any advice given by the author also is covered by this statement. This website and journal is not endorsed by any manufacturers mentioned. This website and journal has no connection whatsoever to any of the manufacturers mentioned. Your use of this information and your use of any advice given by the author is your acceptance of responsibility for all consequenses resulting in such use. No legal liability attaches to the author, the website, or the isp for any inaccurate or misleading information contained on the website and journal at any time or for the consequences of any errors or omissions or for the use of said information. However if written notice is given to the webmaster of inaccuracies or omissions, the author will endeavor to establish the factual position and where necessary correct the content of the website and journal in an appropriate and timely manner.