Why one grower was quick to join MFs Rotary club
Why one grower was quick to join MFs Rotary club
Massey Ferguson took seven
years before it considered
the rotary 8780 combine
was up to operating in UK
conditions. Andy Moore
reports on a Norfolk grower
after his second season
with the machine
WHEN Massey Ferguson decided to field-test its 8780 rotary combine in the UK two years ago, John Davie-Thornhill jumped at the chance to evaluate the machine on his Norfolk farm.
Impressed with MFs previous rotary – the 8590 from the mid-1980s – he was confident the US-built 8780 could offer the same, if not greater, threshing performance and harvesting throughput.
Launched in the US 11 years ago, it took the company no less than seven years to develop the 8780 to suit European harvesting conditions.
"We had the previous rotary on demonstration in 1986 and it appeared to be way ahead of its time and was in a different league compared with straw walker machines," says Mr Davie-Thornhill, who farms near Diss. "The machine displayed impressive harvesting performance in a variety of crops and conditions. This opened our eyes to the advantages of a rotary combine."
To cope with heavier European crops, the 8780 is equipped with an 8.3 litre Cummins engine – increasing output from 260hp to 290hp – which drives a modified rotor.
Measuring 3.65m long, the rotor is powered by a direct drive hydrostatic motor rather than a belt-variator system. This eliminates belt slippage and reduces risk of blockage. A further development is the use of a larger concave fitted with seven sections to thresh greater crop volumes.
The main benefit of the rotor is its ability to thresh crops more gently, resulting in less damage to grain, says Mr Davie-Thornhill.
"Modern farming is becoming more and more quality driven, with milling companies setting ever higher standards for grain quality.
"In addition to cereals, the rotor threshes high protein crops, such as peas and beans, much less aggressively than straw walker combines. This enables us to sell higher quality grain at a premium price under our ACCS crop assurance scheme."
More delicate threshing is also claimed to reduce grain losses when compared with a straw walker combine. This also suits the farms policy of running a machine with spare capacity to harvest a medium size acreage at a steady pace throughout the season.
Mr Davie-Thornhill believes grain losses are also considerably less due to the 8780s shaker shoe having an area of 4.40m sq, together with the concaves seven sections each having 27 rub bars.
Although minimising losses is deemed to be essential, achieving a decent throughput is also considered high on the list of priorities.
Maximum output in a 10.5t/ha winter wheat crop in ideal conditions is rated at 32t/hour or 20ha/day.
Of the farms 580ha (1470 acres), combinable crops include 205ha (520 acres) of winter wheat, 90ha (230 acres) of barley, rye 26ha (66 acres), oilseed rape 65ha (165 acres) and beans 55ha (140 acres).
"Running a combine with slightly extra capacity provides the flexibility to quickly move from one crop to another if quality is threatened by bad weather or crop over-ripens," says Mr Davie-Thornhill. "Producing a higher quality sample from gentler threshing also helps compensate for crops which may have been partially damaged from wet weather or over-ripening."
Further benefits of the rotor system include the ability to harvest crops with moisture levels up to 26%, together with greener straw.
The beater is designed to ensure a constant feed to rotor, while hydrostatic drive allows the rotor to turn and maintain a set speed to allow optimum threshing capacity, regardless of engine speed and crop density.
Should the combines 6.6m (22ft) Powerflow header gobble up large lumps of moist or weed-infested crop – slowing the rotor to 800rpm – oil flow to the motor automatically increases to avoid any undue levels of indigestion. The rotor, together with the header and 1.13m wide elevator can also be hydraulically reversed to help clear plugs of crop.
Extra grunt to harvest heavier crop and to drive a straw chopper is available courtesy of a power bulge facility which increases output from 290hp to 309hp as the engine drops from 2200rpm to 2000rpm.
Another detail to find favour is the machines mechanical simplicity. Because the 8790 is based on a mid-1980s design it has an uncomplicated drive and control system which Mr Davie-Thornhill believes makes the combine easier to operate. *
Above: Blast from the past… The 8780 rotary has been engineered to cope with European rather than American harvesting conditions. Top left: The rotor is powered by a hydrostatic motor rather than belts to eliminate slippage and cut the risk of blockages. Far left: A simple control layout with an easy to read diagram can be set to show running speeds. Left: John Davie-Thornhill says: "The 8780 threshes high protein crops much less aggressively than straw walker combines which preserves grain quality."
MF 8780 Rotary
Engine 290hp Cummins.
Header widths 5.5m to 7.7m.
Elevator width 1.13m.
Rotor 3.56m x 0.70m.
Concave 1.43m sq.
Price £130,575.