Key Lead Corrosion

[stanwood]

Don't inhale that SH--T or you might find yourself stuttering more often.
Lead oxide is POISON!   Don't inhale or ingest it!  It won't go through your
skin.

David C. Stanwood

>Salt air, if you live in CA, FL or HI.  Seal off the lead (e.g., with shellac)
>from the air and the reaction is slowed dramatically.  I have found key leads
>so swollen that I had to break keys in order to get them out of the piano.
>
>Kirk
>
>----------
>From: 	owner-pianotech@byu.edu on behalf of jpiesik@arinc.com
>Sent: 	Friday, June 28, 1996 12:21 PM
>To: 	pianotech@byu.edu
>Subject: 	Key Lead Corrosion
>
>    Subject:  Corroded Key Lead
>
>    What causes the lead in keys to corrode?  Why do some key leads corrode
>    and others do not?  What, chemically/physically, is REALLY happening
>    here?
>
>    Why is it that some pianos only 20+ years old have corroded/expanded key
>    lead while much older pianos have original key leads with virtually no
>    lead corrosion evident?
>
>    Is there a variation in the quality/purity of lead?  Is there a chemical
>    reaction occurring between the lead and the "treated" wood in some key
>    sticks?  Is it an oxidation process that is occurring as a result of a
>    particular atmospheric environment?  Or, is it a by-product of the lead
>    alloy that allows the corrosion to occur?
>
>    What is the best and safest approach/method to correct non-functioning
>    keys because the lead is so "puffy?"  Could one "seal" key lead to
>    inhibit the oxidation process?
>
>    I run accross this symptom periodically in various levels of severity.
>    I suspect we will be seeing much more of this in the years to come.  Can
>    anyone shed some light on this baffling (at least to me) subject?
>
>    Thank you for your responses!
>
>    John Piesik
>    San Diego Chapter PTG
>    JPIESIK@ARINC.COM
>
>
>