Softening hard 1980 Sohmer hammer advice requested.

[Horace Greeley]

Hi, Alan,

At 10:32 PM 11/26/2006, you wrote:
>Hi Thump,
>
>Maybe a moot issue now. But I have a S&S M action in the shop now with
>over-lacquered hammers. I tried washing out the lacquer with acetone. I
>soaked the hammers with a generous helping of acetone. Four applications of
>acetone over 2 weeks. Vigorous needling, squeezing the hammers to try to
>breathe life into these lacquer brickettes. I made almost no progress.

Hmmm...are you sure that they were hardened with lacquer and not 
plastic ("keytop")?  If lacquer, then I would suggest using lacquer 
thinner.  One or two really healthy doses should do it.  If "keytop" 
(which, if from the factory, it is something else), then acetone is 
the right way to go...but, perhaps with a slightly different 
technique.  If you pull the stack, and, rotating it so that the 
hammer tails are free, set the tails into some kind of shallow pan (I 
use old aluminum ice cube trays).  Then, flood the hammers with 
acetone until it runs freely down/out of them.  As soon as you are 
done with that, cover the hammers with aluminum foil and wait...4 - 6 
hours or overnight.  Repeat this a couple of times.  In either case, 
once you see the hardener starting to "run" out of the hammer as you 
apply the next batch of thinner/acetone, blow the hammers out with 
compressed air.

The "trick" in the above is to be patient until whatever hardener has 
been used is again in solution.  Remember that it takes time for 
"keytop" material to dissolve in acetone, and that it is usually 
broken up or relatively thin when that is done.  Once it hardens up 
in a hammer, it turns into a brick...so, getting it back into 
solution is going to take some time.

>Called the piano owner and explained that the hammers were beyond repair.
>Now I'm replacing these with S&S hammers and Abel shanks (it is from the
>teflon era). It'll be interesting to see how these newer S&S hammers sound.
>Hammer #1 weighs 10.1g and #88 weighs 5.2g - unbored untapered.

All of the above said, one does have to weigh the cost of time spent 
rescuing something v. the time simply replacing it.

>You might have better success than I did, but these hammers were the worst
>I've ever seen.

I've done this any number of times, most often with at least 
reasonable results...still, as noted, sometimes the best thing to do 
is to start over.

If you can, I'd suggest seeing if you can keep the old parts to 
experiment with and see if you can (eventually) do something with 
them.  I think that the only such set the I have actually had to 
throw away was one that had been similarly treated and then 
deep-needled to death through the crown.  The poor hammers simply 
fell apart once the hardeners had been dissolved.

  Best.

Horace




>Alan
>
>--Alan McCoy, RPT
>Inland Northwest Chapter
>Spokane, WA
>ahm at webband.com
>
>
>-----Original Message-----
>From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
>Of gordon stelter
>Sent: Thursday, November 23, 2006 11:17 AM
>To: Isaac Sadigursky; Pianotech List
>Subject: Softening hard 1980 Sohmer hammer advice requested.
>
>Am trying to soften the hammers on a 1980 Sohmer grand, 5'7".
>The hammers are those ones with the purple underfelt, and the yellow lacquer
>shoulders. ( What a  color combo !!! ) WAAAAAAAAY too hard !!!!
>Have already sanded out minor grooves, and now planning to "sugar-coat"
>strike points with shallow needling. But would prefer specific advice from
>someone who has already worked with this hammer type, in a similar
>predicament.
>
>       Thanks!
>       Thump
>
>
>
>
>
>
>
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