[pianotech] Joe Garrett's recipe for TP bushings

[Bruce Browning - The Piano Tuner]

Hi Lis
I've recently been tuning a Yamaha C3, fairly old, and some previous
tuners have replaced broken treble strings. The tuning pin bushings seem
to have risen up, proud of the plate, on these pins only, by about
3mm.-4mm.
What could be the cause of this, and should I be concerned.
Bruce Browning
The Piano Tuner.