C88 Hammer Position

[Robin Hufford]

Ron, your method is in general very good but unless the hammer butts are
stabilized it cannot provide the best results.  It is necessary in an upright to
first stabilize the hammer butts by supporting them with a rod.  When the shanks
are removed the butts will fall down and should they be simply lifted up
individually  to the point at which the shank can be installed relative to the
hammer rest rail a substantial inconsistency in their placement relative to the
center pin axis will be introduced.  This will in turn be expressed in regulating
inconsistencies .  To put it  another way:  The hammer butts when viewed down the
rail while looking from the end should all be rotated to the same degree, and
this can only be achieved by a method which fixes their angular displacement to a
constant value.   If this is done then a much greater accuracy can be achieved in
the regulation.   Also, one should mention the utility of sorting the new shanks
by their pitch for the treble.  Robin Hufford

Ron Nossaman wrote:

> >Hi List. I am installing a new action in an old upright. I need to determine
> >the best position for hammer height on C88. On a grand, I have the luxury of
> >moving the action in and out to find best sound. How is this best done on an
> >upright? Is there a general optimal position? Wally Brooks says 1/8" down
> >from top termination. I realize he is quite knowledgable - and I will follow
> >his advice if I get no further input, but I wondered if there were any
> >differing opinions. The speaking length on C88 is 50.5 mm. Or should I put a
> >hammer on C88 a bit on the low side and just lift the action up and down
> >trying to find a best height (seems like things could get out of hand - so
> >to speak). Thanks
> >
> >Terry Farrell
>
> Hi Terry,
> I don't know what should be done, but here's what I do. New butts in, check
> hammer pitch angle by dry fitting a shank and hammer in the C8 butt,
> trimming shank to slightly longer than needed. If you drill your own
> hammers, you did something like this to determine what the pitch angle was
> going to be in the first place. Glue shanks in all of the hammers,
> duplicating the pitch angle throughout. Test fit C8, shaving a little at a
> time from the bottom of the slightly too long shank until you get the right
> length, judged by sound just like you do in a grand. Spot check a few more
> in the treble to see if the strike line is straight and mark the samples
> you have determined are right. Set the rest of the section end guide hammer
> shank lengths where you want them by trim and fit trial. Trim the rest of
> the shanks to slightly shorter than your sample shank lengths, install your
> samples in the appropriate places to use as guides, and install the rest of
> the set from the guides. You will probably have to taper one side or the
> other of the shank to align hammers to the strings as you go. At least it's
> easier for me than trying to bend, burn, and warp shanks all day after the
> fact.
>
> Is it the right way? I have no idea. Probably not, but it has worked well
> enough for me that it hasn't changed much through the years.
>
> Ron N