Bluethner 1916 action

[larudee@pacbell.net]

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The first time I was confronted with a Bluthner Patent Action about five
years ago, I ordered a set of specs from Bluthner (Kasimoff).  The specs
said nothing about whether the hammers were supposed to rest on the
rail, but it seemed logical that they should, so that is the way I
regulated them.

Unfortunately, that left a hammer blow distance of well over than two
inches and key dip of half an inch or more, burying the sharps in the
naturals.  If the height of the rest rail had been adjustable, the
solution would have been simple.  Why did Bluthner make it at a fixed
height, and the height such that the blow distance would be greater than
reasonable?  I concluded that Bluthner had decided to prevent
technicians from making exactly the adjustment that I had intended to
make, and their blow and dip specs would seem to support the idea that
the hammers cannot rest on the rail.  The final confirmation came from a
book called Pianos, Piano Tuners and Their Problems, published in the
U.K., which discussed the Patent Action and showed a picture of the
regulated action with the hammers nicely suspended above the rail.

I have done only two since then, but each one was the same in this
respect.  I don't claim to be an expert, but how else does one explain
these facts?

Nevertheless, you guys are putting doubts in my mind.  The instruments
that I serviced all had replacement hammers.  Is it possible that the
hammers were shorter than the originals?  It would seem strange that the
replacements could have been that far off the mark, but who knows?  In
that case, original Bluthner hammers would have to be awfully long to
start with.  Perhaps it's the rest felt.  Is it supposed to be extremely
thick?  The felt I have seen looked original and already on the slightly
thick side.

I would be interested in any light you fellows can shed on this, but the
only solution I can see short of drastic changes to either the hammers
or the rail is to regulate with the hammers not touching the rail.

Paul S. Larudee

Pianosold@AOL.COM wrote:

> Ola, Paul, and Stephen
>
> The Bluthner specs also say that the hammers on the Patent Action rest
> on the
> rail.  If the blow is correct and the hammers are off the rail - then
> the
> rail covering needs attention.  I use the method that Stephen
> described.  I
> also agree with Stephen's comment above using the corect type of
> 'felt' for
> this.
>
> Uri gella aside! I have not found the 'L' shaped spring that easy to
> regulate.  I don't see how this spring can govern hammer height AND
> drop
> effectively?
>
> Regards
>
> Rob Thornton

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