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Chapter 6-1
CHAPTER SIX
REPLACING A STRING
Although this course "STRICTLY TUNING" does not offer
instruction on piano repair per se, there is one procedure
that is necessary to include in any discussion on tuning.
That is the replacement of a piano string.
No matter how careful you are, and no matter how new a
piano may be, it is possible that a string will break during
a normal tuning. It is more likely to happen on an older
instrument, but just be aware that it can happen any time to
anyone. You should know how to make a number of other minor
on the spot repairs before you take on your first customer,
but for sure, a piano will not make a sound without a
string.
Numerous other minor repairs are explained on the
"BUSINESS" disk which you will receive when you enroll as a
student.
It is possible that in the beginning stage of your
Piano Service Business, you may want to concentrate on
tuning and farm out repair work to other technicians in your
area. This is not a bad idea for a number of reasons:
1. You will be able to begin advertising and tuning imme-
diately upon completing this course. This means $ will
be coming in right away.
2. You will be making contacts with other people in this
business and as a result will learn a great deal about
the prospects in your area.
3. You will not be "pressured" into learning everything
about piano servicing before you start tuning. You can
take your time with the repair phase take on more and
more of this type of work as you are learning.
Of course, if you currently are making a living in some
other pursuit, I would recommend learning all I have to
offer BEFORE you start. This way, when you open your busi-
ness your can advertise "TUNING/REPAIR" rather than just
restricting yourself to tuning alone.
It is beyond the scope of "STRICTLY TUNING" to go into
a complete restringing project. We will concentrate our
efforts here on single string replacement.
First, just as in tuning, you need the necessary tools.
When you look through supply house catalogs, you will see
there are a great many different shape tools to accomplish
the same result. Most of these are excellent so I will not
tell you exactly which one you need, just the type of tool
necessary.
Chapter 6-2
YOU WILL NEED:
A wire gauge
Tuning hammer ( you should already have)
Chain nose or long nose pliers
Wire cutters
Standard type pliers
String lifter
String spacer
Stringing hook
Wire sizes:
12 - 22. Unless you do a great deal of stringing, 1/4
lb. of sizes 12-15 and 1 lb. of the larger sizes will do.
BASS STRINGS - see info later in this chapter
TREBLE STRING REPLACEMENT
Let's assume you are tuning an upright piano and you
are just getting into the upper treble - A string BREAKS!
Do you break out into a sweat? No - you just calmly recall
what I am now going to present.
Recall that in the treble, one length of wire actually
makes up two strings of a unison.
Remove the action by removing the four (or sometimes
three) action bracket bolt nuts, removing the wooden rods
that are attached to the pedals (trapwork), and lifting the
action up and out. Be careful not to damage any dampers on
the action bracket bolts. Stand the action in a safe place
by leaning it carefully against a solid wall or piece of
furniture. Some actions will stand on the action brackets
and some won't. Be careful, or you will wish you had al-
ready studied the repair section on the Business Disk
SEE SPINET ACTION REMOVAL AT END OF CHAPTER!
Now you have all the working room you need to replace
the string. Follow the broken string to the two tuning pins
attached to it. Loosen the pins slightly and pry the coil
out of the eye with a screw driver, then lift the coil out
with your needle nose pliers. Find a clean part of the
string and measure it with your wire gauge. Now, DISCARD
the old wire before you get cut. I speak from experience!
With a tape measure, determine the distance from the
upper tuning pin to the hitch pin. Double it for the dis-
tance of the return trip to the other tuning pin. Now, ADD
8 inches for the extra needed for the coils on the pin. Cut
this amount of wire from the new coil of the same size as
the old string.
Turn the tuning pins out three full turns with the
tuning hammer to allow for the coil and put one end of the
wire under the pressure bar and guide it through the eye of
Chapter 6-3
the right hand pin with the stringing hook. If you are
working on a grand piano put the string on the left hand pin
to keep the new coil out of the way of the second coil.
Make sure the wire is all the way through the eye and
flush with the other side. Then, while holding the wire
firmly with the stringing hook, turn the tuning pin clock-
wise with the tuning hammer until you have two and a half
turns of wire on the pin. Draw the wire down over the
bridge and wrap it around the hitch pin. When you bend it
around the hitch pin, pull it as tight as you can and put a
good bend in it. Now, bring it up and above the next tuning
pin.
You now have to cut off all of the excess wire EXCEPT
for the amount necessary to allow for the three coils on the
tuning pin. The easiest way to measure this is by using the
width of your hand. Hold the wire above the pin between
your thumb and fingers with your hand extended and cut the
wire just above your hand so there will be at least three
inches of wire above the pin.
Guide the string under the pressure bar and through the
eye of the tuning pin. Put two coils on the pin, but no
more. You now have to put the string around the pins on the
bridge and you have to have enough slack in the string to do
this.
With the string lifter holding the wire steady, turn
the pin about one half turn taking care to make the coils
neat and the string not overlapping. Now, return to the
other pin and finish putting the three neat coils on it with
the help of a screwdriver or the string lifter. Put the
final half turn on the other pin and you should have a
string that has three neat coils on each pin, is threaded
around the correct bridge pins and is ready to be tuned.
If the coils are not neat enough, loosen the pin
slightly and make adjustments. Use your long nose pliers to
push the wire firmly into the eye of the pins. Ensure that
the string is firmly against the plate just below the hitch
pin. If not, use a screwdriver and a small hammer to tap it
flush. Use regular pliers and squeeze the wire just above
the hitch pin to help with the stretching process.
Bring the new string up over pitch about four C.P.S.
Since it will fall down quickly, a return trip will be
necessary in a few days to bring it back up to pitch.
If a return trip is not possible from some reason, and
the wire you replaced happens to be one that provides a
string for two different pitches, here is what I sometimes
do. Bring the new string up over the pitch about six C.P.S.
(on both notes) and then place a mute firmly between the two
new strings. You will now have only two strings of the left
and right note sounding, but they will be in tune because
the muted off strings will not be heard. When you return
for your next regular appointment, you merely pull out the
Chapter 6-4
mute and tune the string in the usual manner. It will have
stretched out by then and you should have no problem with it
going below pitch.
If the wire is two strings of the same unison, you can
still mute off the new wire, but be careful that the mute
does not cut off the sound of the one remaining string.
Explain to the customer that the sound will be a bit "thin"
until you return to remove the mute and tune the string.
Also, be sure to explain the extra charge necessary for the
return trip. If you are lucky, he/she may understand...
SINGLE TREBLE STRINGS
Occasionally, you will find a treble string that is not
wrapped around a hitch pin. It will have a loop on the
bottom and will be placed on the hitch pin in the same
manner as the bass strings. If this is the case, you will
have to wind a loop on the bottom of the string either by
hand or with a LOOPING MACHINE available from the supply
house of your choice.
If you have a looping machine, the directions that come
with it are sufficient. If you have to do it by hand, it
gets a little more complicated.
Put a medium size nail in a vice with the head up
better than 1/4". Wrap about two inches (if the wire size
is 12-15 or three inches if the wire is thicker) around the
nail. Then starting about 3/8" from the nail, wrap the wire
around itself with pliers. Make the wrapping as close and
as tight as possible. Cut off any wire you are unable to
wrap and leave only a 1/4" stub.
If this sounds confusing, just look at one of the bass
strings on the piano and this procedure should become clear.
After doing this by hand two times, I purchased a looping
machine. I'm not saying it is impossible to do by hand, but
since you will only have to do this occasionally, you will
have to practice the procedure in your shop every so often
or it will be awkward to do in the customers home. The
looping machine works perfectly every time with very little
practice. The choice is yours.
BASS STRING REPLACEMENT
If a bass string breaks, you have two choices. 1) You
can send the broken string to the supply house for an exact
duplicate, or 2) You can match the string as closely as
possible from a supply of "universal bass strings" you can
obtain from a supply house.
Sending broken bass strings back for duplicates is the
choice if there is no time constraint and the customer
agrees. However, usually it is preferable to use one of the
universal strings. You just purchase a packet of these
Chapter 6-5
strings and carry them to all tunings. The instructions
included are easy to follow and if you learned the procedure
for putting on a treble string, you will have no trouble in
putting on a bass string.
LOOSE TUNING PINS
It is possible that due to the age of the piano, the
tuning pin, after being turned out three turns and then back
in, will be too loose to hold the tension of the new string.
If the pin is on the verge of being too loose before you
begin to replace the broken string, you have two choices.
The recommended procedure is to replace the pin with an
oversized one. You would need a tuning pin gauge to deter-
mine the correct size of the old pin. Usually new pianos
are pinned with size 2/0. You can purchase pins up to 7/0
by the dozen from any supply house. It is a good idea to
carry pin sizes 3/0, 4/0 and 5/0 with you at all times.
The other choice is to take out the old tuning pin and
insert a metal tuning pin bushing in the hole. Replace the
old pin and you effectively have increased the old tuning
pin by two sizes. These bushings are very inexpensive and
are an acceptable repair. If you have to go up more than
two sizes, you of course would have to use a larger tuning
pin.
The procedure is to turn out the old pins, determine
the size and select new pins at least two sizes larger.
Then, using a tuning pin punch (available from the supply
house) and a hammer, pound in the new pins until they are
level with the other old pins. Now, turn out the new pins
three full turns and proceed with the stringing process.
CAUTION: If you are working on a grand piano, NEVER
pound in the tuning pins without using a jack under the pin
block. The jack to use is available from any supply house
and an explanation on its use is included. In an upright
piano, the pin block is part of the structure of the piano
but in the grand, it is an entity all its own and will crack
under hard pounding. If you are only replacing a few pins,
it is permissible to turn in the pins with the tuning hammer
on a grand. However, when completely restringing the grand
piano it is better to pound them in.
REMOVING THE SPINET ACTION
In the 1930's a new type of piano action was introduced
called the "Drop Action". It is identical to the other
typical upright actions except for:
The DROP ACTION or Indirect Blow Action is mostly
placed BELOW the key height. A lifter of some sort (usually
a wire) is attached to the back of the key and extends down-
Chapter 6-6
ward to the bottom of the whippen. When the key is struck,
the lifter wire lifts the whippen and from then on, every-
thing works just as in the "DIRECT BLOW" action.
When removing this type action you must first disengage
the lifter wires from the back of the key - attach them to
the action rail (with string or tape) - remove the action
bolts or screws - remove the screws that hold the bottom of
the action to the piano - detach the pedal rods from the
action and lift it straight up and out.
That is an over simplification of the removal of the
SPINET action, but it is essentially correct.
The important thing to remember is that you must get
the lifter wires out of the way before removal of the action
or you will surely break them when lifting it out.
It is possible that there will not be enough room to
safely lift out the action without removing the keys from
the key bed. If you need to remove the keys, be sure to
number them from 1 -88 with a pencil before removal. Most
manufacturers number the keys on the top, but the numbers
may be hard to read.
ALSO, be very careful when lifting out the action so
you do not damage the dampers on the tuning pins or rods
that the action brackets are attached to.
Removing the Spinet Action is more or less a common
sense procedure, but since there are so many different types
of drop actions out there, I have included a more complete
discussion of this procedure in the Repair section on the
Business disk.
You can also request service manuals directly from the
manufacturer when in doubt.
The information presented in this chapter should be
sufficient for the occasional single string replacement.
In this chapter, you learned:
1. Tools necessary to replace piano strings
2. Treble string replacement
3. "Single" treble string replacement (how to make a loop
in the string)
4. Bass string replacement
5. What to do in case of loose tuning pins
6. Cautions on pounding in grand tuning pins
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