Negative bearing

[David Love]

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I'm restringing a Steinway A (6'4") c 1925.  The bearing measurements =
are as follows:

Note #           80         60         40         22         10
Front         +.030    +.018    +.012    .000      .000
Back          -.018    -.012     +.006     .000   +.015

The negative bearing on the back of the treble portion of the bridge and =
the low bearing in the upper part of the tenor section are my concerns.  =
It appears to be related to the height of the aliquots.  My thought was =
to grind them down.   Moving them forward would lower the bearing but =
would detune them.  The positive bearing on the back of the bass bridge =
can be reduced with a bit of felt at the hitch pins.   Any comments on =
the following questions:

1.  Is that the best way to proceed?
2.  What is a good target for positive bearing on the back of the =
bridge?
3.  How critical is the bearing on the back of the bridge for tone =
production. =20
4.  Will not correcting it create concerns for rolling the bridge =
forward over time?  (though it hasn't done so yet apparently)
5.  What method would you use for thinning the aliquots?

Part 2:

The soundboard has small unopened cracks.  There is no rib separation, =
some of the cracks do not even go through.  Normally, because they are =
so small, I would simply scrape the board clean and refinish without =
shimming.  In this case, the customer (have you heard this before) wants =
to only spend money on items that affect musicality or structural =
integrity--cosmetics is unimportant.  Because the cracks have =
compromised the varnish seal over the board, is there any potential down =
side to not refinishing the board.  The finish overall is in good =
condition. =20

Thanks,

David Love

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