#1
Simple question - Does using gas dusters (the type usually used for computers and such) on Rosewood boards to get gunk out from the below the strings dry out and ultimately harm the wood?
#3
If you are getting the fluid on it, maybe... you can get insta-frostbite if skin contacts it so I'm willing to bet getting it onto the fretboard is damaging.

But if it's not getting onto the fretboard (they don't have that much pressure so I don't see how it'll work?) then you should be just fine.
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