First off-let me say I'm new to guitars, so this may be a noobish question.

I've got a 50 year old Gretsch with original tuning keys and they're tight as hell.

Are these able to be oiled without ruining anything?

If so..what oil/lube do you recommend and how do you recommend applying it?

I know noting about Gretsch guitars but 9 times out of 10 they will have a screw on the end of the key so you can adjust the tightness.

If not, well I don't know what to tell you. I can't see a little oil hurting the keys but then again I don't know.
American Strat:
Area 61 Neck, Area 67 Middle & Bridge
Spretzel Locking Tuners
Graphtech Nut & String Tree
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