because the hour hand has moved/slipped .
1) Let the clock strike on the hour and COUNT the number of strikes,
2) now where ever the hour is gently rotate the hour finger round to correspond with the number of strikes that the clock did.
if the finger falls off gently push it back on (in the right place of course)
wirecutterman, June 2009
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I can answer this question...
grandmother clock won't chime the appropriate hour?