Health & Safety
Evolving from Manual Mowing
Today, petroleum-based products are essential to farm operations. But for thousands of years, fodder – speci cally, hay – was the most critical form of fuel on the farm.
For centuries, grass was cut by workers who walked through pastures or elds wielding small, sharp scythes. In addition to being tiring and slow, manual cutting was ineffective— the scythes worked well only when the grass was wet. �e rst mechanical grass-cutting device appeared in 1830, when an English textile worker named Edwin Budding developed a mower allegedly based on a textile machine used to shear the nap off of cloth.
Today ' s grass mowers are lighter, sleeker, better behaved, more easily controlled, more durable and a whole lot bigger than they used to be. Improved suspension and weight distribution allow machines to be worked at faster forward speeds with greater con dence, while bed designs have been developed to be strong yet cut close to the ground, with shear-bolt and discshear technology minimising collateral damage when things go wrong.
Look also for blade mountings that allow knives to be changed quickly without grazed knuckles yet hold them securely when discs are spinning at colossal speed. In terms of size and sophistication, the choice has never been greater – from a simple 1.2m( 4�) tractor-mounted disc-bed mower for modest paddocks to a multi-armed 480hp selfpropelled giant that can fell 14m( 46�) of forage with each pass. Nor is there any shortage of con gurations, with rear-mounted, front-mounted, combination and“ reverse drive” options to extract maximum productivity from any size of tractor.
Mowing without conditioning If the grass is to be spread out to dry, why bother conditioning it on the mower? �ese machines cost less, weigh less and do not need as much power as their conditioning counterparts, so they can be run on smaller, lighter and more economical tractors, especially when operated in front / rear and triple combinations.
Improving the ride Suspending a mounted mower ' s disc cutting bed from a support arm via a central pivot rather than from a pivot at the inner end of the machine is reckoned to improve the machine ' s ability to respond accurately to irregular surfaces.
It is certainly becoming a more common design feature of mounted mowers, along with more sophisticated spring and / or hydraulic suspension systems that try to cater for demand for faster mowing speeds. Operators sitting comfortably in their suspended cabs are more inclined to drive faster in the eld, a�er all.
�e mounting arrangement also improves weight distribution and reduces the height of the machines when folded for transport. Effective suspension is even more important on front-mounted mowers because of the different forces involved.
Most designs involve a linkage and spring arrangement that“ pulls” rather than“ pushes” the deck to improve contour-following responses while keeping the weight on the disc bed to a minimum without detracting from cutting height accuracy.
Mowing back and forth It ' s not a new concept but there more trailed mower-conditioners capable of cutting to the le� and right of the tractor.
Apart from the advantages of cutting up-anddown rather than in lands or round-and-round, which means double swaths picked up by the forager will always be parallel, there is a positive conservation bene t.
Cutting in this way gives animals and game birds a better chance of escaping unscathed than when they are corralled in“ lands” or at the centre of a eld in the path of a fast-moving mower.
Make mine a triple Triple mower combinations are increasingly popular among contractors and farmers with large acreages of grass to cut ahead of a selfpropelled forage harvester thanks to their combination of high output with good eld manoeuvrability and easy road mobility. Making most of the output potential with accurate steering is a challenge that can be made a lot easier with a GPS auto guidance system.
�e one-front-two-rear con guration is most popular as it spreads the out t ' s weight, but having everything on the back is an alternative. Working widths are typically from just over 7m( 23�) but can go to almost 9m( 29� 6in).
November- December 2016
FARMERS
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