HAMMER FIT

[Les Smith]

Hi, Doug. Welcome. Since this is your first set of hammers, I'll try to
make it easy for you. The following is ONE WAY to do it. Given the caliber
of the technicians on this list, you are sure hear of others. First, I hope
that you didn't remove all the hammers from their shanks yet. Start by
spacing the old hammers to the strings, so that all are properly aligned.
Next, remove EVERY OTHER old hammer. This will give you two old hammers
with which to align every new hammer that you install. Despite the wear
on the old ones, this will allow you to match up the strike points of
the new hammers with the old. Next, I would recommend that this time you
don't use hide glue. It dries too quickly and you're going to need some
extra working time. So, instead of hide glue, use an alaphactic resin
yellow glue such as Titebond, or Elmers. As you install the new hammers,
it will give you time not only to align the strike point of the new hammer
with the two old ones, but also let you "travel" the new hammer with the
two old ones as well. Later on, when you gain more experience, you can
switch to hide glue if you like. Right now use something that gives you
some extra working time. Now, about the hammers being too loose on the
shanks. Make yourself some thin paper shims, about 1/8" x 5/8", or 1/8"
x 3/4" long and insert them between the shank and the bore of the hammer.
You may have to experiment with a thickness of paper that gives you the
right fit. Don't forget that the glue will take up some of the slck too,
so don't make the dry fit with the paper shims too tight. Make sure that
you get glue on BOTH sides of the paper shims. When you've installed every
other new hammer, you'll find that the first ones are dry enough that you
can now remove the remaining old hammer heads and then install the remain-
ing new hammer heads, aligning them with the new ones you just glued on.
When using the paper shims, one of the signs of a good job is to trim off
the excess paper, to insure that it doesn't show. Lots of hammers are in-
stalled with shims, but you'd never know it because the tell-tale excess
is trimed off. See? Really a piece of cake and not nearly a difficult as
you thought it would be. Good luck and have fun!

Les Smith
lessmith@buffnet.net

On Mon, 19 Aug 1996, Doug Richards wrote:

>      Howdy to the List,
>
>      I am new to the piano repair industry.  I recently decided to replace
>      a set of hammers on a grand piano because of excessive wear.  Having
>      never done this before, I am not sure about the fit of the hammer
>      shank to the hole.  From previous postings and other sources, it
>      sounds like the fit should be "snug".  Since I had not done this
>      before I decided to have the Supply house drill the hammers.
>
>      When I checked the hammer to shank fit, it felt too loose.  The hammer
>      shanks in the knurled ends measured .220" and the hammers were a snug
>      slip fit on a .235 cylinder.  This much clearance between parts seems
>      to allow the hammer to rock excessively without glue, and the strike
>      point would be difficult to control.  I assume the hide glue will take
>      up some of the difference, but since the fit is so loose to start
>      with, will the glue joint be compromised?
>
>      Do I send the hammers back, or am I missing something?
>
>      So before I go any further, I need a volunteer and would be happy to
>      donate 2-3 cents for comments and/or instructions...
>
>      Thanks,
>
>      doug
>      drichard@qntm.com
>