I have done some steaming on hard hammers that wouldn't respond to needles and it works fine. It's quick (by the time you can get the action back in the piano) and lasts a while. For truly long term softening of very hard hammers, I still like the fabric softener (1 part Snuggle 7 parts isopropyl alchohol.) It seems to last until you file that felt off. Just put a little on the striking surface, and dry with a hair dryer. Works best on hammers so hard that needles won't penetrate. Dave Porritt SMU - Dallas
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