New millstones installed at Heatherslaw Corn Mill

The stones, which weigh over a tonne each, were gifted to Heatherslaw Corn Mill by ADM Milling in West Yorkshire after an appeal on the BBC.

They were delivered to Ford and Etal Estates last summer but have been fitted over the past four weekends, the operation overseen by local engineer Matthew Rawlings who volunteered his time.

The process of lifting and replacing a pair of stones may sound relatively simple but given the weight and size of each stone, the logistics were complex and a certain creative licence had to be employed.

Shifting the bed stone, which sits underneath the top stone, was particularly problematic. A hydraulic power pack was utilised to help lever and lift it from the spindle, but this alone was insufficient so a car jack was pressed into use. Once lifted both stones were manually rolled to the exit.

Phase two saw local farmer William Bell utilise a telescopic loader to lift the new pair of stones to the top of the entrance stairs so that they could be rolled towards their new home. He was part of the team that helped shift the original set of stones into position when the mill was restored in the early 1970s.

Heatherslaw Corn Mill’s chain hoists were utilised to lift the stones, which were then levered into position with old fashioned sweat and muscle. The bedstone was then wedged and shimmed from underneath to ensure it was central and level and the drive shaft bearing repositioned within the centre of the stone.

Matthew and head miller, Mark Robinson, adjusted and fine-tuned the position of both stones until they produced a flour that met his exacting standards.

Once this first new set of stones are successfully up and running the current working pair, worn out from half a century of flour production, can also be lifted and replaced. This two-stage process ensures flour can be produced without interruption.

Heatherslaw Corn Mill has operated on a single set of stones since the 1970s, though back in the days of peak production the mill had the capacity to operate six different sets of stones at the same time.

For now, a leap from utilising just the one set of stones to two is seen as huge advantage. This will enable Heatherslaw Corn Mill to double its production capacity and, excitingly, to mill two different types of grain simultaneously, water levels permitting.

Both sets of new mill stones are made from French buhrstone and are a like for like replacement of the old stones. Buhrstone is a hard quartzite rock which hails from Northern France.

An industry grew up there in the 1800s shaping the stones, cementing them with plaster and reinforcing the construction with an iron band. The finished product was exported all around the world as buhrstone millstones were thought to produce a superior flour.

ADM Milling, one of the world’s largest agricultural processors and food ingredient providers, had a number of old millstones at its site in Knottingley and kindly offered to donate two sets of stones to Heatherslaw.

To celebrate, all entry charges will be dropped for the first month of the 2023 season (March 27 to April 30).