[pianotech] String replacement in overstrung area

[Joe DeFazio]

> From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org]  
> On Behalf Of Matthew Todd
> Sent: Tuesday, December 16, 2008 6:08 PM
> To: pianotech at ptg.org
> Subject: [pianotech] String replacement in overstrung area
>
> I am figuring a quote, and I just wanted to be sure of something.
>
> Is the only way to replace a treble string that passes under the  
> overstrung area by loosening tension of all bass strings and  
> removing them from their hitch pins?
> TODD PIANO WORKS
> Matthew Todd, Piano Technician

Hi Matthew,

If you have a soundboard steel (that long, thin, flexible piece of  
spring steel for cleaning soundboards), you can use that to guide the  
new tenor string under the bass strings and to the hitch pin (if you  
don't have one, get one - only a few bucks and highly worthwhile!).   
Assuming that the string is the typical type found in american and  
asian pianos in which one piece of wire makes two speaking lengths, I  
often do the following  (I am assuming an upright, but this method  
works for grands as well with slight variation required):

Measure both unisons from the hitch pin to the tuning pin.  Add the  
lengths, and add several inches for making coils (I would add at least  
eight inches or even more, if it is your first time).  Cut a length of  
the proper diameter wire.  Fold the wire into almost equal halves  
(remember that the two tuning pins will invariably be staggered, and  
if you disregarded the directive to leave a little extra wire, try to  
fold the wire to accommodate).  Use masking tape to attach the folded  
part of the wire to the end of the soundboard steel, so that the  
remainder of the wire runs along the steel.  Feed the new wire/steel  
under the bass strings.  Fish out the folded end, undo the tape, and  
loop the bend around the hitch pin.  Temporarily attach the wire to  
the hitch pin with Vise Grips or anything else you have (I've even  
used string wrapped tightly around the hitch pin above the music wire  
and a drop of CA in a pinch).  Ignoring the bridge for the moment  
(except to make sure that the string is not diverted from its  
relatively straight path by an errant bridge pin), draw one string  
slightly taut, measure to final length, and cut the small amount of  
excess.  Make sure that the upper-pitched and lower-pitched wire  
segments are not crossed.  Feed the wire around/through whatever  
bearing surface is present, make a coil on a dummy pin, and install  
the coil on the "real" pin.  Follow the same procedure for the other  
wire/pin.  Add just a small amount of tension to the wires, enough to  
take up slack, which will make the next step easier.  Use two small  
tools (screwdrivers, whatever you have - I use a small brass rod with  
a pronounced "V" filed into the tip, and sometimes a little hook made  
of #22 wire) to coax each wire around the proper bridge pins.  Get the  
wire around one pin, then use a small tool to hold it tightly against  
that pin while you use another tool to coax it above/around the other  
bridge pin.  Here, you may have to somewhat let down the tension on  
one or a few bass strings for tool clearance, depending on the  
circumstance.  Remove the Vise Grips, dress the coils and seat the  
string at the hitch as normal, and tune.

On days when I have run into this problem without my soundboard steel,  
I've used my "magnet on a telescoping stick" tool instead;  most  
problems can be solved with ingenuity and the contents of your  
toolkit.  With experience, these kinds of situations go from nearly  
impossible, to difficult, to a routine challenge that makes your day a  
bit more interesting.  Folks with more experience than I have may  
report that it eventually gets to "unbridled joy."  I'm not there  
yet.  I bet someone reading this has an even easier method (maybe the  
stringer, which I've never sprung for)....

I'm really glad that you asked, for two reasons.  One is that removing  
all of the bass strings will present a near-term tuning instability  
problem, and cause unnecessary wear on the pinblock (the healthy block  
will withstand it just fine, but the borderline block will often be  
worse for the wear).  The other is that I don't think that it is right  
to charge customers for a large job when a more skilled technician  
could do a small job successfully instead.  When starting out,  
probably almost all of us have done just that at least once or twice,  
only because we didn't know better at the time.  I bet we almost all  
feel bad about it in retrospect, and I'm glad the situation is averted  
here for you.  So keep asking those questions!

Joe DeFazio
Pittsburgh
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