striking point for new hammers

[anthony]

Thanks for the info John, I tried marking 1/16 down on the top note 
strings,speaking length of 50mm,which is 3.1mm,looks right, but 1/8 of the 
note 1 speaking length(1256mm) is 157mm which is almost in line with the top 
of  dampers at that end.

Judging as close as I can the striking point at the base end should be 133mm 
below the v bar which with a horizontal line to the other end comes very 
close to the 1/16 of the speaking length at the top note(3.1mm)

do you think the idea of duplicating the ratio at several points from 
another piano is valid?

thanks again,Tony



----- Original Message ----- 
From: "John Delacour" <JD at pianomaker.co.uk>
To: "Pianotech List" <pianotech at ptg.org>
Sent: Thursday, August 02, 2007 10:05 AM
Subject: Re: striking point for new hammers


> At 6:19 pm +1000 1/8/07, anthony wrote:
>
>>         l'm about to fit a new set of hammers to an old wilcox and white 
>> angelus upright piano which has had the old hammers removed and also new 
>> tuning pins and strings installed.
>>
>>my question is related to the striking point,is there a rule of thumb that 
>>is accurate enough for this?
>>can you use a ratio of the speaking lenght at several positions and draw a 
>>line betwen them?
>
> Go down 1/8 of the speaking length on note 1 and 1/16 of the speaking 
> length on the top note and you'll probably find the line joining them (the 
> strike line) is horizontal.  If not, get a piece of card, rest it on the 
> action beam at the top note and mark it 3mm below the top bridge. 
> Transfer this mark to the bottom string and join the two points.  Note 
> that some pianos raise the hammers above the line a little towards the 
> tenor break to make room for longer dampers.
>
> JD
>