
Originally Posted by
Simon Barden
Unless they are really, really rattly, tuners rarely allow any slip. I've had one set of tuners (on a min 1940s Regal parlour), where the tuners were so bad through wear they had to be replaced.
Slippage that bad is often a sign of the strings unwinding at the ball ends. This is quite a common occurrence on the top two plain strings, less so on the wound strings. Though sometimes the wrap or wound strings can sometimes lose its grip on the inner core and cause issues.