Checks cause hammer bounce ?

[RicB]

Hi William.

Thanks.  I suppose I'm going to give this a try for sure.  But to be 
honest, and despite the fact I agree that most of the <<diagnostics>> 
point to the balance rail (except the fact that there is no movement 
without the hammer comming into check) point at the balance rail.  
Problem is ... I'm really good at bedding screws and bedding in general. 
At both the Hamburg and the Hamamatsu acadamy this was commented on.  I 
know for sure them screws are both in contact with the keybed.

I guess I just get the feeling that something else can be causing this 
hammer bounce that most of us have just guessed at.  Hammer rail flex 
for example, is often brought up... but I've yet to find a diagnostic 
that can actually confirm those things can get involved, and I dont 
quite fathom how so much energy gets transfered up there to actaully 
flex that rail enough to cause the bounce.  I'm a bit off the wall this 
way.... when my head scratches I just cant seem to sit easy.... Like I 
say... I have run into this only a couple times.  I know of two Yamaha 
(Both C7's) and this Steinway where I cant seem to get the bass hammers 
to sit easy on fff blows... and all three have this connection to the 
back checks thingy.

So... I suppose try both Ron O's suggestion and Jon Pages support to the 
letoff rail on the Steinway.

One question on the dial thing... tho I suppose its in the article 
(which I have to dig out anyways).. Different keyframes require 
different kinds of pressure on each bolt.  For example Steinways call 
for fairly even pressure (partially due to the bowed front rail as I 
understand it) and Yamahas specify most pressure on the middle and tenor 
break glide bolt ... creating a bow that way.  Does Rons Dial article 
come complete with a set of specs for different actions ?

Cheers
RicB


    Not to beat a dead horse here, Ric, but it seems like your
    diagnostics are
    leading you to the balance rail.  I recognize that there are still
    possibilities elsewhere, but perhaps it's time to get that dial
    indicator
    after all.  ;-]

    maybe:

    http://www.leevalley.com/wood/page.aspx?c=2&p=32525&cat=1,43513,51657

    or something of that nature.  I'd have to look up Ron O's article,
    but I
    assume this indicator would work well enough.

    Best,
    William R. Monroe