Strange Attraction

I noticed a very silly thing today.  If you still have your spanner in your hand when you are trying to line up the weathervane to north you get some very strange readings from your compass.
 
Spent a few minutes at 13.00hrs, that’s midday GMT, lining up the new anemometer to true north.  I managed to find our old magnetic compass so I had belt and bracers to get things right.
 
Many thanks to Admirer for hosting Silly Saturday