Warwick Bridge Mill update June 2018

 

The millwrights have been very busy, both on site and back at their base where replacement timbers for the control sluice and the escape sluice gate have been prepared. On site the cast iron components of the wheel have been cleaned and inspected; the stone cut pit for the pit wheel cleaned out; the stones lifted and inspected and the Hopkinson roller mill cleaned.

 

The roller mill following cleaning, June 2018

 

Charles Hopkinson, Millwrights and Engineers of Retford in Nottinghamshire also supplied the elevators. The castings for these are dated 1874 and 1875 and were presumably installed, with the roller mill, as part of a general upgrade of the mill equipment.

 

The removal of the timber remains of the control gate allowed access, via the wheel pit, to the head race tunnel.

 

Looking through the stripped out wheel and the ironwork of the control gate into the head race tunnel. The first of the replacement timbers in place.

 

A variation in the profile of the tunnel vault indicates that the head race tunnel has been built in two phases. Initial thoughts suggest an upstream extension to the race tunnel. The additional 1.5.m (c.5 feet) would have given additional capacity to the loading dock above, perhaps when the area was given overhead cover and could be used for temporary storage. The tail race tunnel shows similar evidence of a two stage development. An in filled timber slot and an iron fixing in the northern tunnel wall, corresponding with the break in the vault, may indicate the position of an earlier trash screen at the entrance to the shorter tunnel.

 

Break in the head race tunnel vault towards the upstream end, showing the variation in the profile of the tunnel vault. Looking towards the south wall. Considerable evidence of later re-pointing of the tunnel walls in hard Portland cement

 

The timber lining on the tunnel floor, seen end on last month, extends upstream 90cm (c.3 feet) from the wheel pit cill as far as slots for substantial timbers (15cm/6 inch wide) in both the race walls. The extent of the timber floor corresponds with the remains of planks extending up both side walls to the springing of the tunnel vault, forming a waterproof wooden trough within the stone tunnel on the immediate approach to the wheel. This structure gathered the water and directed it downwards in a controlled stream into the waterwheel buckets in the most efficient manner.

 

Remains of the planking lining on the south wall of the head race and rebate for heavy timber in wall at the upstream end of the lining. The slotted ironwork lying on the tunnel floor formed part of the control gate structure, directing narrow streams of water into the buckets. The timber lining extends upwards beyond the springing of the vault where water would surge behind the control gate

 

Pinions and rollers for the racks operating the timber control gate. As the gate was raised a narrow stream of water was directed downwards to fill the buckets in the most efficient manner

 

At the head weir and the site of a former sluice, upstream from the mill where the head race leaves the Cairn Beck and passes under the main road through the village, a cast iron plate set into the weir records a re-build by the Eckersley brothers in 1918. Mathew managed the mill and the brothers also had a shop next door in Warwick Bridge. Walter also managed a shop in Heads Nook.