case parts and a pin

BSimon1234 BSimon1234@aol.com
Fri, 16 Jan 1998 08:23:23 EST


Someone wrote:

<<We also have a practice tuning piano with a broken tuning pin.  It is a
modern Kohler console.  The pins are so tight that the common broken
tuning pin extractor will strip out before it moves the pin.  There is
about one quarter of an inch protrudeing from the pinblock.  It is the top
pin and is in the valley so has pins on both sides of it makeing it
difficult to get at it.  Any suggestions on how to remove it for
replacement?>>


In conjunction with any of the proper methods for pin removal, consider
reducing the pin torque with heat. You have a lot of pin on which to put an
extractor tip. Put on the extractor tip tightly, then heat it with a torch for
a few seconds and try backing it out. ( Use a tiny torch or very tiny tip,
sideways, just hitting the tip of the extractor, protecting everything around
the pin.  In my shop it would be possible to use an acetylene outfit with a
jewelry welding torch tip directly on the pin stub.  It puts out a flame only
1/16" long)   Alternatively, you could heat the tip of a punch to red hot,
-and I actually do mean red hot,  because transfer of heat will not be that
good anyway, then press it onto the tip of the pin for a few seconds, then
extract. With a hot punch you do not need to shield anything around the pin.
High heat, fast, should heat the one pin sufficiently without affecting its
neighbors, whereas slow heating with a soldering gun may make a whole area
hot, and doesn't work very well anyway.

Consider worst case scenario. You fall asleep and inadvertantly heat the pin
until it chars the few thousandths of an inch of pinblock around itself, then
it practically falls out.  Simply drill out the wood to the diameter of the
hole in the plate,  plug the hole with pinblock material, epoxied in,  and
redrill for a new pin. 

Just a thought, or two.

Bill Simon
Phoenix



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