Harry, List, You have obviously received some more excellent thoughts considering your desire to have your Schimmel's voice to arrive somewhere between bright and where it is, and have it stay there for awhile. I noticed that some are against using plastic/acetone on any hammers. That's fine and well to take that stand, but certainly does not negate the reality it is one practiced method used in the piano service field, and one that has merit in certain applications. I mentioned earlier that the strength ratio might not have been enough. After reading your post again, it is possible that the ratio was more than enough, but was applied very sparingly in the crown area that produced the initial brightness, then dissipated over time through use. Another area that has not been mentioned is the regulation of the piano's action. There are several adjustments, that if out and put back in perspective, can dramatically change how you perceive the voice of your piano. Ideally, finding a technician who has experienced the effects of all the methods mentioned, ironing, needling, filing/shaping, hardening, regulating, will be your best option; and then the communication that takes place between you and that technician, to determine just what it is that will bring your piano around to where you want it, will be vital. Best, Keith McGavern Registered Piano Technician Oklahoma Chapter 731 Piano Technicians Guild USA
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