Instruction Manual

14
SAFETY
General Safety Guidance
1. The excavator should be correctly maintained and operated by a trained and competent
person.
2. The banksman and machine driver need to establish a system of communication which is
thoroughly understood. It may be appropriate to wear radio communication equipment in
conjunction with appropriate PPE, to ensure consistent safe communication.
3. We believe that when correctly operated, the Autoguide Postmaster is safer than a
conventional falling weight post driver. Nevertheless, take care to avoid contact with the
machine and stay out of its working area whenever it is working. Fence posts can fail
unexpectedly so stay out of the working zone of the machine.
4. Hydraulic oil can cause severe injury, either because it is at high pressure or high
temperature. Take care to check hoses and connections and rectify any damage or leakage.
5. The Postmaster has proven to exceed its original design objectives. However, it must be
accepted that satisfactory performance will only be achieved in conjunction with sympathetic
operators, careful work planning and optimum base machine performance.
6. The basic concept demands the use of a twin shaft vibrator, which results in pure vertical
movement. The vibrating weights must overcome the dead weight of the gearbox, post
clamp and the post. The rubber mounts allow this vibration to take place whilst causing the
least possible vibration of the excavator hitch and boom.
7. It follows that larger excavators (usually up to 3 tonnes) will deliver better performance as
they have greater mass made up of hitch and boom components.
Optional Flow Control Valve
On larger diggers, an additional flow control valve is
required to limit the flow to the Postmaster, to prevent
excess oil flow to the Postmaster motor. Excess flow will
result in over-speeding of the vibrator and will damage the
motor. The flow control valve is set in the factory.
In the event that the Postmaster is connected to a smaller
excavator, it may be necessary to open the valve in order to
achieve adequate vibration speed.
It is important to do this gradually i.e. 1/4 turn at a time (counter clockwise), to achieve an
optimum cycling speed. Note: Turning the valve clockwise will further reduce the flow.
It should also be noted that the vibrator speed is proportional to engine revs, so running the
engine at high rev/min may also over-speed the motor.