Really,, lead is basically inert as an element. Have you ever had a battery post expand?
The air surrounding the lead may cause some oxidation on the surface which happens to all metals but does copper or steel expand in salty environments?
Also,,, I have seen this happen in the mountains where I live. The clue is when Will from Hawaii said it doesn't happen to all the leads.
The answer,, The lead used in some of the weights was from recycled lead and was contaminated
Same as the Young Chang brackets and other pot metals that are mixed from what is available.
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Keith Roberts
owner
Hathaway Pines CA
209-728-2163
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Original Message:
Sent: 04-03-2019 07:45
From: Karl Roeder
Subject: Bosendorfer Key Lead Expansion
I drilled through the leads with a 1/8th" bit over a bucket to catch the dust and most of them disintegrated to the point I could clean the hole with a bore brush. The few that didn't come out on their own I was able push out with a straight punch by hand. The key for me was coming up with a way to clamp the underlever in place to lessen the chance of damaging the wood. I was removing them from the rail in case that wasn't obvious.
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Karl Roeder
Pompano Beach FL
Original Message:
Sent: 04-03-2019 05:38
From: David Love
Subject: Bosendorfer Key Lead Expansion
Karl
What method did you use to extract the expanded lead?
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David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
Original Message:
Sent: 04-02-2019 23:01
From: Karl Roeder
Subject: Bosendorfer Key Lead Expansion
Mr.Love,
I had the same thing happen on a Bosendorfer 225 from the same time period. The piano had been in Colombia for a number of years where it was re-finished. In this instrument it was only the underlever leads that corroded and I always suspected some sort of exposure to a corrosive gas during re-finishing. My thinking was that the keys and stack were removed while the back action was not. I found that .32 caliber wad cutter bullets (cylindrical and tin plated) were a near perfect fit for the originals installed by Herrburger-Brooks. I was lucky and only one of the underlevers had cracked due to the expansion. Bullets (as distinct from cartridges) are easy to find at most local gunshops that cater to the re-loading crowd. Using them in a piano is perhaps the best use one could put them to in a swords to plowshares sort of way.
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Karl Roeder
Pompano Beach FL
Original Message:
Sent: 04-02-2019 18:06
From: David Love
Subject: Bosendorfer Key Lead Expansion
Couple of pictures of a tortured piano. Bosendorfer 225, c1970s with expanding leads in both the keys and damper levers. Every one of them binding against its neighbor. Fortunately no apparent splitting of the keys. Have not run into this on a Bosey before. Seen it on other pianos though. Remove and replace I guess is the order of the day. Nasty stuff.
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David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
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