in-the-home boring jig

[Newton Hunt]

First, if you have a change of tone it is most likely because the
hammer was not filed before or after installation.  ANY amount of
misalignment will cause a change in tone so the hammer has to be
files.

The supply house sell a metal hammer boring fixture that does a good
job of boring individual hammers.  I think it is call a Quadrill Jig.

		Newton