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I want to replace some classical style (9.4mm plastic) machine heads with metal 6mm shaft Grover Sta-tite tuners in a slotted head instrument.
this:- http://ramavioloes.wixsite.com/rama/modelos-cavaco
the Grovers come with 9.1 bushings. I reckon the hole size must be 9.6, so that's obviously too small unless I use epoxy to glue them in. The other alternative is to buy larger ones. I can find 10mm, so thats about 0.4mm (0.015748 inches or 1/64th) compression.
Is that about right?