Action is too low
Instruments- discuss specific features, luthiers, instrument problems & questions
You've got the nickel & dime idea WRONG.
The strings should just touch a dime setting next to the first fret.
They should also just touch a nickel balanced on top of the 7th fret not the 6th fret.
If open strings are sharp before playing -- how sharp is sharp?? A few cents? Half way across the dial? If the instrument is in tune when you put it away --- and is sharp when you come back to play again -- you have some serious environmental issues going on. Where are you storing it. in direct sunlight at any time? In a cold back room?
Ok I rechecked it. The dime does fit nicely between the string and fretboard at the first fret. The nickel won’t fit anywhere between the frets and strings. Should that be corrected before I try other fixes? What would be the fix? Shim the saddle or replace it?