Spearhead TWIGA 120, Handbook

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Spearhead TWIGA
120
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Breakaway Protection Breakaway Protection Breakaway Protection Breakaway Protection
A mechanism is built into the lower mounting points to allow ‘breakback’ of the machine for
protection of components in the event of accidental contact with immovable objects. The
sprung mechanism works in conjunction with the lift ram base pin allowing the feature to
transfer to the whichever side the machine is operating on. When encountering an
obstruction and the tractor continues to move forward the free suspended link will pivot
about its mounting bar and allow the complete armhead and frame to move up and back
until the obstruction is cleared or the tractor brought to a halt. Resetting of the breakaway
is completely automatic with the armhead returning to the work position under gravity.
WARNING: It is important to understand that this feature is for component
protection in unavoidable circumstances only, the breakaway geometry gives
limited movement and therefore should not replace the operator’s responsibility to
avoid potentially damaging situations.
Tractor Control Settings
Refer to the tractor’s hand book to ascertain the correct control settings to suit the type of
machine and the hydraulic installation.
Operational Limitations
The TWIGA 120 is a light hedge trimming tool - attempting to cut unsuitable material will
cause the knife to stall resulting in the tractors relief valve blowing and overheated oil.
Tractor Engine Speed
The tractor engine should be run at a speed which will give 2½ - 4½ gpm (12 - 20 litres) of
oil flow to the cutterbar motor. Less will be insufficient to do the work; more will result in
increasing cutterbar vibration and greatly accelerated wear.
Tractor Forward Speed
This is a matter for common sense and experience. It must be fast enough to maintain the
correct oil flow but slow enough to enable the cutterbar to do its job properly.
Highway Working
If it is intended to cut roadside hedges or to work in the vicinity where the public have
access, it is a statutory requirement that suitable warning signs are placed at both ends of
the work area. These signs should not be more than ½ mile (0.8 km) apart. To further
promote highway safety the use of headlamps would be beneficial. Hazard warning lamps
should not be used as oncoming vehicles could easily misjudge braking distance in
presuming the tractor approaching them is stationary.
Cutterbar – Unclogging, Checking or Adjusting
Before leaving the tractor seat select ‘Cutterbar Off’, switch off tractor engine and remove
the starting key. Should the cutterbar become clogged NEVER, NEVER, NEVER clear any
debris from the fingers or knife with your hands - use a stick from the hedge or other
suitable tools.