[pianotech] 1098 Hammer Bore

[Encore Pianos]

I had a similar problem with an old M & H screwstringer upright where I was
installing new hammers, shanks, and brass rail butts.  It has been my
practice in terms of convenience to have my supplier bore and shank the
hammers for me, and I then cut the shanks to length in a jig and glue them
into the butts while at the piano.  I ended up with a gap about the same
size - the replacement shanks were the smaller Abel upright shanks, while
the brass rail butts required the 7/32" upright shank.  I was uncomfortable
with the amount of slop and did not believe that I would get a trouble free
fit and accurate alignments, so I sent the hammers back to the supplier.  I
then had the supplier bore another set for 7/32" but not install the shanks.
I ordered the 7/32 shanks from another supplier, glued the shanks in the
hammers, and glued them into the butts per my customary hanging practice.  

I thought about doing what you are considering, but rejected the idea
because it just seemed that the hammer would be too loose everywhere else -
if you centered that shank in the hole, you would have about .008 everywhere
around it.  It's just wrong, and to consider anything else is to invite
trouble.  The fact that the bore distance is too short also should be the
straw that breaks the camel's back, and push you to the decision to get
another set.  

Of course, how that plays out with the other tech and the customer is
another matter.  But don't make his problem your problem.  

I don't know if these are Steinway factory hammers or from a supplier.  If
it is an aftermarket supplier you may be able to get them to redo the set
properly without charge.  That would be the first avenue to explore, before
you plug and rebore.

If there is someone out there who knows how to properly determine the proper
bore for an upright action, given the rake of the hammers, I would love to
be educated about that.  

Good luck, 

Will Truitt



-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Jon Page
Sent: Thursday, February 14, 2013 8:28 AM
To: pianotech at ptg.org
Subject: [pianotech] 1098 Hammer Bore

I was handed a project that another tech could not finish due to a family
illness. New hammers are in the offing but I have a few concerns. 
First, the shanks mic .210" but the hammers were bored to .218" (7/32). 
That is way too loose. Could a paper shim be glued in on the non-string side
of the molding without causing a problem down the line? Secondly, the
hammers are bored close to the same length as these old, worn ones and there
are shims under the hammer rail already. What is a stock bore 
for a S&S 1098?   Maybe I should plug these holes and rebore to bring 
the action parameters to original specs.

Regards,

Jon Page