bobble heads rule(r)

[Mary C. Smith]

>When you test on the bench do you use a string height gauge and play a
>pianissimo key strike?
>
>Ed

Ed asks an important question here. If you don't use a string height gauge,
the hammers, when played, will go up further than they do in the piano, and
have more momentum coming back down into the backcheck. Thus, they will
check better on the bench. I do experience this problem ALL THE TIME on the
practice room L's and M's I maintain. I find that a combination of
1)ensuring that the backchecks are high enough (i.e., top of backcheck is
1/16" below bottom of tail at let-off), 2)roughing tails lightly with 60
grit paper, 3)slightly lower drop, and 4)slightly less spring tension will
accomplish checking in even the most recalcitrant pianos. Good luck.