[pianotech] weights of hammers and shanks/replacement parts

[David Stanwood]

Hi Julia,

Perhaps the lowest tech way of matching hammer weights to match 
existing key weights is to dry fit clusters of sample hammers hammers 
mid-bass, mid-tenor, and mid-treble and find that weight that gives 
you down weights in the high 40's.  Check the up weights and if they 
are below 20 your friction is too high and if they are above 30 your 
friction is too low...  I say clusters because no particular key 
weighting is likely to be similar to neighbors so you have to look 
for average levels in each of the three major sections...

Use a digital scale accurate to 0.1 grams to measure the weights.

If you want to know what weight level your hammer are you can refer to:

http://www.stanwoodpiano.com/SW-HWstandards4.pdf

If you want to measure 88 of the ready to hang hammers, look at a 
graph of the weights using excel and come up with specifications to 
smooth out the bumps you can go to:

http://www.stanwoodpiano.com/E-SmartChart2.4.xls

The weight of the modern parts isn't your main concern... plenty of 
modern pianos play beautifully... it's not the parts so much as the 
configuration of the weight and leverages... and keep an eye on that 
friction!

It's an extensive subject and very important to our work.... Hammer 
weight is the place to start!

Good Luck,

David Stanwood

>Greetings,
>
>                  This is the first Steinway that I am replacing 
>hammers on. I would like to just replace what is there. The keys 
>have 4 to 5 lead weights in the bass. I don't think I should change 
>it.
>
>        What are the pros and cons of just replacing parts that are 
>there vs removing key weights and changing ratios and weights?
>
>        Is there any reading I can do to help me through this job? I 
>have replaced hammers and regulated before...on uprights, and pianos 
>like Lester grands, but I have never done a Steinway and the whole 
>weight figuring before.
>
>          When replacing hammers and shank/flange assemblies, does 
>the weight of the shanks along with the hammer weight affect 
>downweights/upweights...or is only the hammer weight alone a factor 
>for regulation?
>
>Thank You,
>Julia Gottshall
>Reading, PA