Hello Richard, Don and Barbara,
A few more comments interposed.
First, I did try today the use of alcohol as a wetting agent; it
was useless as it served only to accelerate the reaction and
immediately harden the mixture as Don Rose predicted it would. Also,
while applying it to a piece of bushing cloth as Barbara considered
doing it was obvious that there really was no need for a wetting agent
as it disappeared almost instantaneously upon being dripped onto the
cloth. There was no discernible puddling or lag time. Again, this was
a Don predicated. Two for two. It may be however, that the
penetrabilty of this mixture may be different in a bushed flange whether
the pressure in the bushing may have to be taken into account. The
obvious effect of this stuff was to stiffen and harden slightly the
cloth as I intended.
Richard Brekne wrote:
> Hi again Robin, a couple comments below
>
> Robin Hufford wrote:
>
>> Hello Richard,
>> ..... However, simply because the claim is made that the bushing
>> is hard doesn't mean, in my experience, they will be, perhaps yes,
>> perhaps no, perhaps sometimes and one probably will not know when
>> until perplexing difficulties arise. One can take the
>> hammershank and flange in hand and hold the flange tightly while
>> trying to wiggle the shank in a way so that the pin can be made to
>> move back and forth in the bushing and watch this motion. A soft
>> bushing will show more motion of the pin in the bushing and that is
>> a serious problem as it has a really detrimental effect on the sound.
>
>
> Herein lies at least one tentative test for Barbaras flanges and it
> would be nice to hear what she observes in this regard. Up to this
> point I've been taking for granted that the bushings in question were
> as previously described.
>
>
>> Sometimes, as I Barbara and I both have experienced, repining is only
>> a temporary improvement; in the face of such a frustrating experience
>> I tried the method I described. It appears, as I said, at least for
>> the moment to have both worked at the time of use in stabilizing the
>> friction and wobble and led to no discernible subsequent pining
>> problem. But, again, its purpose was to deal with an overly soft
>> bushing.
>
>
> I have to admit I've never tried the kind of solution you describe
> above, being hesitant to apply any chemicals at all to either hammers
> or bushings. Too many unsatisfactory experiences for my part.
In general, I thoroughly agree: A clean pin, of the right alloy,
with a proper woven felt cloth, properly densified, I think, can be
shown to have worked for generations reliably and can continue to be
expected to do so. Why fiddle around with anything else? A lesson, in
my opinion, these various companies should take to heart. But they
don't and they put out, generally for frivolous reasons, the kinds of
products of which we are taking note of here. But, in this case, here
was a problem in need of a solution, which, in the case of my use of the
technique, appears to have worked.
> What I have found works very well is to work a good deal of teflon
> powder into the bushing and burnish very agressively followed by a
> rather tight pinning. Generally if I do have a problem afterwareds it
> goes in the opposite direction and I need to loosen things up a bit.
> Perhaps I might give your suggestion a try tho on some spares I have.
> Never thought of using CA in this context before.
>
>
>> If I were Barbara in this situation I would find two or three really
>> weak sounding notes from the middle and low treble and change nothing
>> else but the density of their bushings with the mixture, or take the
>> time to use water with alcohol, and judge from the results. I think
>> is absurd even to have to do this lesser task by necessity but even
>> more so when it is necessary to take the time to rebush parts for
>> which one has already paid good money to have acceptable bushings
>> come along with the rest of the order. I'll have to climb down off
>> my soapbox here before I get myself really worked up!
>> Regards, Robin Hufford
>
>
> Agreed, should be an un-needed operation for high quality parts. But
> then, assuming these are the new NY Steinway parts... we (I at least)
> dont know really what these are like from the get go. That said... the
> whole concept of bushings with such low friction does not appeal to me
> in the first place.
It doesn't to me either: I am not sure it is even a valid technical
idea and it seems this idea may only be a stop-gap attempt to deal with
the problems of geometry, excessive mass and friction which one sees in
the present production.
> RicB
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