Product category:
Gears, brakes, couplings and engines
News Release from: Siemens Flender | Subject: Redbournbury Water Mill
Edited by the Engineeringtalk Editorial
Team on 04 April 2002
Gearbox aids water mill restoration
Flender Power Transmission has donated a Motox gear unit to an 18th century water mill that has been restored to full working order, and which now sells the flour it grinds.
Flender Power Transmission has donated a Motox gear unit to an 18th century water mill that has been restored to full working order, and which now sells the flour it grinds Redbournbury Water Mill near St Albans is based on the site of a Doomsday mill, so flour has been ground there for a thousand years
This article was originally published on Engineeringtalk on 3 Jun 2008 at 8.00am (UK)
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Once belonging to the Abbey of St Albans, and seized by Henry VIII when he dissolved the monasteries in 1539, it remained mostly in crown hands with tenant millers until 1987 when it was sold to the present owners.
Damaged by fire that year, it was fully restored with a grant from English Heritage and now contains many artefacts loaned or donated from local museums and other mills.
The Motox-N Z88 gear unit was given to the mill by Flender in response to a plea for help from the volunteers who have been carefully restoring the mill over a 10-year period.
Due to many years of overabstraction, the mill stream in the Ver Valley was no longer sufficient to run the water wheel on its own, especially in summer, and so a large 1935 Crossley oil engine was obtained and restored to run the mill whenever the river was low.
The Flender gear unit has been positioned with the motor inside the mill, while the engine outside the mill drives the generator.
The Crossley single cylinder engine has an 11in bore, 18in stroke and a 7ft 2in diameter flywheel weighing 2.5t.
It is rated 55bhp at 270rev/min and its total engine weight is 4.5t.
By contrast, the Flender Motox-N weighs just 203kg, and is a Z88-G160L4 helical geared foot mounted motor unit.
Its power is rated at 15kW, speed is 301rev/min and gear ratio is 4.87:1, with a service factor of 2.43.
Justin James is a member of the restoration team and part owner of the mill.
He commented on the donation: "The Flender unit has been one of a number of generous contributions, and is working brilliantly! Without it we would not be in the position we are today; making several tonnes of organic stoneground flour which we sell at a small profit, and more importantly enabling people to view a real mill in motion".
The Ver Valley Society is trying to encourage water savings in the area, but growing public consumption remains an ongoing challenge.
The Ver is one of the last chalk streams in the country and an important natural habitat to a variety of wildlife.
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