Bouncing hammers.

[David Love]

I think he is talking about the hammers rebounding off the rest rail and
back into the strings rather than bobbling on top of the jack.  Since the
wippens have assist springs, my vote still goes for the tension being to
high.  Be sure that the springs only just float the wippens.  If they are
lifting the wippens hard up to the drop screw then you can get bouncy keys
and thus bouncing hammers.  Disconnect a couple of springs and see if it
still happens.  If it does, analyze the front weights to see if you can add
lead without exceeding front weight maximums and decrease the tension on the
springs to keep the balance weight the same.  Using the assist springs for
9-10 grams of weight should not be a problem, over 15 grams you run some
risk.

David Love

----- Original Message -----
From: "Dick Beaton" <rbeaton@initco.net>
To: <pianotech@ptg.org>
Sent: October 31, 2001 4:25 PM
Subject: Re: Bouncing hammers.


> Hi Victor...
>
> The reason for bouncing is that the jack is not getting out of the
> way...."let-off".
>
> First check your key dip.
>
> If that is OK, then check to see if the key height is correct.  You may
have
> to raise the center rail a small amount on the bass end to get the key
> travel far enough to do the job.
> If that isnt enough, then you need to set the let-off
>
> About all I can think of...remote control like.  Best wishes,
>
> Dick RPT MT
> ----- Original Message -----
> From: victor belanger <vbela@MIT.EDU>
> To: <pianotech@ptg.org>
> Sent: Tuesday, October 30, 2001 8:27 AM
> Subject: Bouncing hammers.
>
>
> > Hello all,
> >
> > May I indulge with y'alls expertise.
> > I have a Mason & Hamlin concert grand here that in the bass, the hammers
> > bounce quite a bit after the note is being struck and the hammer returns
> to
> > the rest rail. In fact it bounces so much that on a staccato blow
> sometimes
> > it can hit the string/s again. I have a pianist that pointed it out to
me.
> >
> > I played around with the adjustable hammer rest rail. If the rail is
close
> > to the hammers, it seems like it is worse. The only deduction I can come
> up
> > with is that the hammers are too heavy. But really they are not.
> > BTW. The pinning is fine.
> >
> > How can I avoid this problem? Why is it doing it only in the bass?
> >
> > Thanks.
> >
> > Regards.
> >
> > Victor
> >
>