Steinway hammer Bore Angles

[Jon Page]

>  I wasn't aware that there should be a fan in the angles in the bass

Because of the angle and close proximity of the hammers it is advisable
to lessen the angle as you go down the bass. The single strings certainly
do not need much. The greater the angle, the tighter the clearance.

For an A I would probably bore:
Degrees,Hammer count
Bass notes 1 - 20
5,6
6,2
7,2
8,2
9,2
10,3
11,3
Tenor notes 21 - 51
11,4
10,4
9,3
8,3
7,3
6,2
5,2
4,2
3,2
2,2
1,2

If the hammers are really tight together at the top of the bass and you don't
want to make then more narrow you could bore 10,2 & 11,2 and increase 5,8.

In the tenor you could bore 11,3 & 10,3 and increase 6,3 & 5,3. Or you can
adjust the groupings to end up at 90 degrees lower in the scale. Your call,
there is room to play.

I don't think there's a hard and fast rule except for having the hammers
as parallel to the strings as possible for unicorda but I find that boring
above 11 degrees poses clearance problems.

For pianos which have strings that are severely angled I don't try to match
hammer angle to string angle.  I've seen original hammers bored to 16 degrees
but opted not to duplicate.
-- 

Regards,

Jon Page
-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20060410/87e4f09f/attachment.html