Geograph - photograph every grid square

National Mills Weekend is an annual celebration of the UK's milling heritage. The event is organised by the Mills Section of the Society for the Protection of Ancient Buildings.
The 2012 dates were the 12th and 13th May. Over 450 buildings were open to visitors meaning many to choose from. They ranged from fully working wind and water mills to under restoration or rarely open buildings.

In a mill context, tentering is changing the distance (gap) between the runner stone and the bed stone. Decreasing the distance results in a finer grain. As the stones go faster there is a natural tendency for the runner to rise and the tentering mechanism can be adjusted to counter this. In many windmills this is done by a governor that automatically compensates for the tendency of the runner to rise. In watermills it is done by hand with mechanisms of varying elegance. In this case, the second order lever at the bottom raises or lowers the footstep bearing that the spindle carrying the stone nut is supported by. The adjustment is by a vertical lead screw on the other side of the frame and in easy reach of the miller.