huge pitch raises

[Dave Nereson]

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    Before doing a big pitch raise, I always tighten the plate screws =
first, especially on older pianos. Heck, even new ones often need the =
plate screws snugged down.  The ones that bug me are the verticals where =
the bottom plate screws are not accessible because of the trapwork board =
being right in front of them.  If it's really flat and the other plate =
screws are quite loose, I'll tell them I have to come back with my piano =
tipper to tip it on its back, remove the bottom board, and tighten plate =
screws.  According to last month's Journal, the chances of breaking a =
plate just from pitch raising is very slim, but I don't want to risk =
anything.  Besides, the tuning will probably be more stable if all the =
screws are tight.  In case you don't know, don't crank down on the nose =
bolt nuts -- maybe just make sure they're snug.
    As for lubricating, I do it only if the strings are rusty or if =
there's evidence of strings having broken in the past.  Don't lube the =
upper plate bridge, or bearing bar of the bass strings.  Any liquids =
that run down onto the widings will make them go dead.  Elsewhere, I =
suppose Protek or other lubes are fine as long as you don't use too =
much.  I've sprayed WD-40 into the cap of the can, then dipped a =
toothpick into it to apply tiny amounts, rather than spraying anything.  =
But as someone else suggested, seating the strings on both sides of the =
bridge helps to loosen any "set" or rust bond.  And filed hammers, =
minimum lost motion, and strong blows help to get the strings vibrating =
so they'll "render" through their various bearing points easier (I =
believe).  And let the string tension down a wee bit before yanking it =
up.  "Yank" might be a bit strong, but I've had better luck letting the =
string down the tiniest amount possible and pulling it up to pitch all =
in one quick motion and with one blow of the key than with repeated =
pounding and a slow pull up to pitch. =20
    I do all the middle strings of the tenor and treble, then right-hand =
strings coming down and left-hand strings going up, then the bass.  =
Everybody's got their own sequence.  I've tried the "one big wave" =
method of starting at the bottom and doing unisons as I go, all the way =
to the top.  It didn't seem any more accurate or stable than my other =
method, and was slower.  It's just a rough-in.  You have to start over =
and fine tune anyhow, and if it's coming up more than an eighth- or =
quarter-step, it's not going to be a stable tuning for long.  I just =
tell 'em it'll hold better next time as long as it's done within a year. =
 They can't expect to let the piano go 5 years without tuning, then =
expect a pitch raise and tuning to hold it for another 5  years!

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