Last week we heard from our volunteer millwright Vince about the work that is under way at Nether Alderley Mill, our sister property. This week I’m handing over to Bruce, one of our Power Volunteers to hear all about the water wheel’s Blind replacement that has been happening here at Quarry Bank…
The Norfolk Millwright Alliance has been engaged to replace the blind on the waterwheel at Quarry Bank Mill. The current blind was fitted when the wheel was installed nearly 30 years ago, and now has deteriorated to the point where it no longer allows the water flow to be shut off completely, thus compromising the control of the wheel.
The new blind has been fabricated from water buffalo hide, bound together with steel strips, and is a direct copy of the old blind. Though we always speak of “the blind”, it is in fact two blinds, as the penstock has a division in the middle, and therefore there is a blind on either side of the division. Each blind weighs approximately half a ton.
The first new blind arrived at Quarry Bank in the back of the millwrights van, and was carefully unloaded and manhandled into the chamber beside the waterwheel.
Before starting work in the penstock (the trough of water the millwrights are standing in, in the picture below), it was necessary to secure the counterweight – which weighs about 508 pounds – to ensure that it was safe to start dismantling the blind controls.
The chains which control the operation of the blind were removed followed by the bars securing the bottom of the blind to the penstock. Next the blind was cut up so that it could be removed in pieces of a manageable size.
The final piece was the largest and heaviest. Once this was out it was possible to see a view not seen since the wheel was installed, in particular the wooden roller on which the blind is moved up and down.
With the old blind out, the new blind was lifted carefully into position over the penstock – given its weight, and the limited access, this was quite a long and delicate operation.
Finally, the blind secured at the bottom, folded over the roller, and with the operating chains attached – though there is still a little more work to do before it is fully ready to be used.
So that’s one done, one to go – but the second blind may not be as easy, as the access to the right hand part of the penstock is rather more restricted, with large beams above it:
The work on the water wheel is ongoing, and the Norfolk Millwrights Alliance will be returning later this week to install the second blind, until then, the water wheel will be out of action.