I have found Protek on key bushings to start squeaking after much playing, particularly on a piano with PianoDisc installed. I use a pipe cleaner dipped in Teflon to swab bushings and balance rail hole with good results. Someone else I know swears by plain ole mineral oil wiped on the pins. Dean Dean May cell 812.239.3359 PianoRebuilders.com 812.235.5272 Terre Haute IN 47802
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