Renovation(4) - 7th September 1999
The wheel is now painted and the lining boards and the cross timbers which
form the "bucket bottoms" or "stretchers" are in place.
Still to be done - fit the fronts to the buckets, replace the wooden teeth in the "pit wheel" and then organise a water supply. The old weir is broken and the leet is blocked.
One authority suggests that the burr stones rotate at 100 - 150 revolutions per minute. ("The Miller and Milling Engineer" by Charles E. Oliver, Indiana USA 1919)
The stone nut has 21 teeth and the spur which drives it has 88. The wallower which is directly connected to the spur has 31 teeth and the pit wheel which drives it has 66. The pit wheel is directly connected to the water wheel.
The suggests that the water wheel should turn at 11 - 17 revolutions per minute when working.
There are 42 buckets on the wheel and each measures 40" x 10" x 5" (3" at the base and 7" at the top) or 1.15 cubic feet or about 7 UK gallons of water when full.
That is 294 gallons per revolution or 3000 - 5000 gallons per minute will be needed under working conditions!!
If at any one time 12 buckets are doing useful work then there will be about 840 pounds weight of water acting around a centre at 6 foot radius then at 17 rpm there will be a force of 85,680 foot/pounds per minute but 1 hp is defined as 550 ft/lbs per second thus this wheel will develop 2.6 horse power at 17 rpm and 1.7 hp at 11 rpm!!!
The authority quoted above also says that a 4ft burr stone running at 150 rpm needs 7.5 hp????
|Fitting the lining boards||Two pit wheel teeth and a locking piece.|
|The completed wheel(Summer 2000)|