Upright Treble Hammer Weight

[David C. Stanwood]

Hi Terry,

Before we get started would you please post the hammer weights for notes# 
16,17,40,41,64,65?   This gives a better thumbnail of what's going 
on.     This "Minimal Sampling" is middle c, c# and double octaves either 
side.  Just measuring first and last doesn't tell use what's going on in 
between very well and that's were the pianist action is!

Thanks,

David Stanwood

>I am replacing hammers in an old upright. I have a concern regarding 
>hammer weights and how they follow (or rather don't follow) the Stanwood 
>curves. I have used Stanwood curves in the past to weigh off upright 
>hammers for tonal purposes - I realize it affects touchweight minimally - 
>although it does affect the inertia portion of touchweight.
>
>I have purchased a set of Isaac Credenza hammers for the piano. SW for the 
>A0 is about 10.8g - right in the lower end of the midsection of Stanwood's 
>curves, and probably about right for a smallish piano (52"). SW with the 
>Isaac C88 is 6.9g - right at the most extreme heavy treble hammer on the 
>Stanwood curves. I presume reducing treble hammer weight will provide 
>better tone for the piano (maybe not - I guess a 9-foot grand has a 
>similar speaking length?). As you can see in the picture below, the 
>original C88 core is a lot smaller than the Isaac - 1.7g compared to 2.9g. 
>If the new C88 hammer had a core like the original, that hammer weight 
>would fall in about the middle of the Stanwood curves - a much better 
>match for the bass.
>
>I wonder how any Pianotech List participants (and/or lurkers!) have 
>addressed control of upright hammer weight in a situation like this.
>
>I don't have any similar new hammers where C88 is much lighter to try to 
>compare tone.
>
>And what the heck kind of wood was used on these old actions? It is very 
>dark right through - some kind of cedar (no pleasant odor)?
>
>Thanks for any thoughts.
>
>Terry Farrell