Slow Hammer Return

[Vanderhoofven]

At 05:44 PM 2/20/96 -0700, you wrote:
>In a message dated 96-02-20 08:12:18 EST, you write:
>
>>
>>Does this YC have wippen helper springs at the wippen flange?
>>Does the adjacent wippen have helper springs.
>>
>>
>
>The answer to both ?'s is no.
>
>A simple solution is to weigh the functioning key from the key pivot to the
>front of the key and remove lead from the bad key until they are the same.
>
>If there are helper springs adjust the weight to be the same then adjust the
>spring tension until the down weight is the same.
>
>If there is only one helper spring remove enoughg lead weight to make the key
>function reasonably well.  Remove the front most weight first.
>
>     Newton
>     nhunt@rci.rutgers.edu
>
>
>
>
>I thought about weighing the keys, but didn't know exactly what kind of a
>weighing device to use.  By the way Mil gratzie for the help.
>
>Dick Day
>Marshall, MI

Dear Dick,

Sorry about responding so late.  My e-mail got backed up!

The device used for weighing piano keys would be a set of gram weights.  The
set of gram weights I have (and all I need for now) is a set from Schaff
Piano Supply.  The part number is 198 and it costs $7.08.  The weight set is
made out of machined brass, and there are 6 weights in the set, measuring 1
gram, 2 grams, 4 grams, 8 grams, 16 grams, and 32 grams.

It is possible to diagnose friction and weight problems in a piano action
using the gram weights.  The gram weights are set on the front of the keys
(where your finger pushes down on the keytop) and different amounts of
weight are added or removed from the set until you can get the correct
reading for downweight, and upweight.  There have been quite a few postings
by others about this topic here on this list (in the archives).  You can
also purchase a set of JOURNAL reprint articles from the Piano Technicians
Guild about Hammers and Touchweight.

The inexpensive set of weights from Schaff will serve your purpose for now,
but later you may want to purchase a more accurate (and more expensive!) set
of gram weights from Bill Spurlock, or Pianotek or other sources.

I would reccomend not adding or removing leads from the keys, until you
check for proper friction in the action.  What may appear to be a problem
with too much or not enough weight in the keys can actually be caused by
tight action centers.  After you have checked the pinning at the action
centers and checked the friction at the keypins, then you can move on to
adding or removing key leads.

I have seen several pianos that had a jiffy lead stuck onto the back of the
key. After I removed the jiffy lead, it became readily apparent that there
was too much friction in the action of that note.  The jiffy lead was just
masking the real problem.  In my opinion, working with the key leads is the
last thing you do, after you check the action for proper friction.

Hope this helps!

Sincerely,


David A. Vanderhoofven
dkvander@clandjop.com
Joplin, Missouri, USA
Associate Member, Piano Technicians Guild
web page:  http://www.clandjop.com/~dkvander/