Key lead oxidation

jpiesik@arinc.com jpiesik@arinc.com
Mon, 04 Nov 1996 11:49:50 -0500


Hi Bill,

The next issue of the PTG Journal should cover key leads.  I know because Steve
Brady will be kicking the discussion off with a question I asked on this list
earlier in the year.  I'm looking forward to it - hope it's helpful to you, too!

Here's what I've learned:  There does not seem to be any method to "seal" or
slow down the "oxidation" process of lead.  Because of the different "blends" of
lead alloys (some are more pure than others) the swelling is actually occurring
as a result of an internal chemical reaction between two dissimilar metals in
the lead alloy itself.  Much like that in a battery where the lead reacts
chemically with acid to create electrical current.

The best solution appears to be to replace the bad lead with good, pure lead.  I
don't think any amount of "sealant" would stop or inhibit the swelling (internal
chemical reaction).  Ever wondered why some keysticks with 100 year old lead
look as good as new, while other keysticks, only 20 years old or less, are a
swollen, powdery mess?

Regards,

John Piesik
Piesik's Piano Service
Carlsbad, CA
JPIESIK@ARINC.COM

P.S.  Here's another "quote" that would help all of us, including me, become
better communicators:

"Be quick to listen, slow to speak, and slow to anger."  God

List -

Is there any practical way to slow the oxidation process once key leads
have begun to swell, short of replacing the leads?

I have the action from a Wurlitzer grand, where the leads have swollen
to the point of freezing the keyboard.  Once I have sanded them back
flush with the key sides, does anyone have a treatment to recommend
that will make the sizing more permanent?
Bill Maxim, RPT, Piano Technicians Guild    wmaxim@gnn.com
Serving South Carolina from Columbia and Greer

"It is better to keep the mouth shut and seem a fool than to open it and remove
all doubt"  Chinese Proverb





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