Just hanging on to the bottom of this thread, please.
I recently bought a parlour VINTAGE guitar, WITH STEEL STRINGS, and had the shop lower the action before I took it home. Now, after some two months, the action has reverted to it's former height. Does this always happen or is it just my bad luck to have picked an instrument that couldn't hold it's alignment ?
Could I re-tighten the truss rod again or do I risk doing damage ?