Greetings,
I let the threads find their own center by getting the button started
and then allowing a rotation or two to tell if it is not straight on. If it
is, I just hold the button while the screw turns in. (maybe spending a few years
over a potter's wheel helps with eye-balling a centered rotation!).
Regards,
Ed Foote RPT
http://www.uk-piano.org/edfoote/index.html
www.uk-piano.org/edfoote/well_tempered_piano.html
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