Although Jack Windmill is now devoid of machinery, evidence of such remains today.

The "beehive" cap, constructed of lapped timbers, rotates on a circular curb to bring the Sweeps into wind by means of a Fan.

The five floors, from top to bottom, are the Gear floor, Bin floor, Stone floor, Spout floor and Ground floor, from which an underground passage leads to the Granary.

Restoration of Jack began in September 2012 with the construction, by volunteers from Sussex Mills Group, of a temporary roof.

In March 2013 the original cap was removed and the temporary roof was installed. The refurbished cap, complete with a new Fan, was lifted into place on 16th March 2017.

After a period of testing and monitoring, the Fan was released in August 2018, allowing Jack's cap to automatically turn to wind for the first time since 1909.

Update - February 2026 : Jack Windmill's owners have set up pages on Facebook and on Instagram.

These feature vintage photos as well as news on the repair works to Jack Windmill and to the Roundhouse of Duncton Windmill.