Thank you Mr. Mannino ( for polite verdigris answer )

[gordon stelter]

Your comments below were the most helpful except:

1) Verdigris is not a  generic term. It is only
apllicable to copper corrosion. "Verd", as in "green",
as I'm sure you know. 

2) If pins can be had of other materials, they may be
less prone to corrosion as copper is particularly
reactive. This, combined with a  thorough cleaning of
the bushings and parts would be a second-best choice,
I am sure. New parts are not available for Brown
actions, as far as I know.

3) Many of us are not in the ideal condition ( for the
technician ) of having customers willing to spend
boodles on their 130 year old Chickering. So we look
for "best alternative" solutions, hopefuly without
eliciting snide derision from those from whom advice
is sought. ( Not you..... some of the other guys who
responded !!! )

Heart-felt ( Hey! that's  a pun! ) thanks for
providing more useful info in your post that all the
others combined. And for being kind.
     G
    


--- Don Mannino <donmannino@comcast.net> wrote:

> At 05:36 PM 7/29/2005, you wrote:
> >THAT'S NOT WHAT I ASKED !!!!!!!!!!!
> >VERDIGRIS is an oxidation of COPPER without COPPER
> it
> >CAN NOT EXIST!!!!! In the felt, or the pin.
> Probably
> >the pin. So what is the composition of pins today,
> so
> >that it can't arise. SIMPLE QUESTION!
> >Sheesh!!!!
> >      Thump
> 
> Sheesh, Gordon.  No need to yell.
> 
> The green oxidation is merely a side effect of the
> problem, not the 
> problem itself, so your title statement is not
> correct.  Our term of 
> "Verdigris" is just a term we use - it indicates
> contamination of the 
> bushing, and we call it this whenever we see the
> green color, but 
> really the problem is the contamination / gumminess,
> not the green.
> 
> So the paraffin and oil used, over time, did 2
> things: They got thick 
> and gummy, and they caused a chemical reaction which
> oxidized the 
> copper (brass, really) at the same time, especially
> when combined 
> with high humidity.  You can get the same effect by
> applying WD-40 to 
> action centers - after many years it will gum up,
> and there will be 
> oxidation of the brass as well.  It's not the brass
> causing the 
> problem, remember, but the contaminant which was
> applied to the 
> bushing.  If you eliminate the copper, the
> contamination and 
> gumminess will still be there, the sluggishness will
> be just as bad - 
> it just won't turn green.
> 
> To prevent the problem one must eliminate the
> contaminant completely, 
> after which the brass pins should behave themselves.
>  My experience 
> with many different cleaning solutions has not ever
> produced 
> permanent resolution.  Some cleaning processes might
> give good 
> performance for a couple of years, but those pianos
> which I have 
> tried my best on have always gotten sluggish again
> after 1 or 2 
> years.  That's why most people recommend replacing
> the parts 
> completely as the best and safest solution to the
> problem.  Works every time!
> 
> I hope this makes the issue a little clearer, Thump.
> 
> Don Mannino RPT
> 
> 
> 
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> 



		
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