Specifications

300 SERIES MAN HOLE DIGGER
FORM GOM12070702, VERSION 1.2
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pin to retain the earth auger to the transmission
driveshaft. This pin is not intended to shear when the
auger comes in sudden contact with a buried object.
The pins are utilized for the following reasons:
a) Such an occurrence (pin shear) would result in
extensive physical damage to the driveshaft and auger
drive hub.
b) Even if the physical damage to the Hole Digger could
be eliminate and/or minimized from the actual
processes, it could require an unknown (and potentially
large) number of auger pins to complete the digging
process for any specific hole.
c) Even if the cost of the replacement auger pins is not
a factor, the resulting productivity produced by the
actual process would not be deemed acceptable by
industry and/or social standards for the Hole Digger.
d) Given the infinite number of soil conditions which
could be encountered during the actual process, it is
impossible to design and supply a specific auger pin to
shear at a specific torque value which would produce
acceptable operational results for the Hole Digger.
e) Given the infinite number of operators and their
methods utilized during the actual process, it is
impossible to design and supply a specific auger pin to
shear at a specific torque value which would produce
acceptable operational results for the Hole Digger.
f) Given the infinite number of combinations of soil
conditions, auger diameter, auger boring head
condition, digging depth, mechanical operating
condition, operators and operator methods
encountered during the actual process, it is impossible
to design and supply a specific torque value which
would produce acceptable operational results for the
Hole Digger.
6) For comparison purposes, it is interesting to note
that portable electric drills do not utilize any torque
limiting or clutch device to allow the drill bit to slip at an
specific torque value for drilling purposes. As with a
Hole Digger, such a devise would make the drill a
useless tool because of the infinite number of potential
operating configurations and the inability to design
specific components to meet the requirements of each
operating configuration.
7) Many portable electric screwdrivers incorporate a
torque limiting or clutch device which allows the
operator to preset the torque output of the tool to a
specific value. This is especially useful and desirable
when hardware is secured to specific torque values
according to industry published standards.
8) Portable electric drill and screwdrivers are two
separate tools designed for different and specific job
applications. The drilling process has different
requirements than the fastening process offered by
screwdrivers. The operational characteristics of
portable electric screwdrivers can not be confused
and/or substituted for the operational characteristics of
the Hole Digger.
OPERATING THE HOLE DIGGER CONTINUED.
Application:
All 300 Series models.
5) Auger boring heads are designed for digging in a
wide variety of soil types and/or conditions. Each boring
head design represents a compromise in overall
digging efficiency, productivity and service life for any
given soil condition. As a general rule, pressing down
on the operator handles is not required to initiate and/or
sustain the digging process. In most soils of moderate
Proctor Densities, augers will dig at rates that will not
cause the centrifugal clutch to overload and slip. In
most soft soils of low Proctor Densities (sandy, etc.), it
may be necessary to hold up on the operator handles
to reduce the digging rate of the auger. The natural
tendency of any auger design, in low Proctor Density soil
conditions, is to dig at a rate which causes the centrifugal
clutch to overload and slip. In most hard soils of high
Proctor Densities (hard clay, etc.), it may be necessary to
press down on the operator handles to establish and
maintain acceptable digging rates. Proper digging
procedure for any given soil condition is the
accumulation of actual experience, skill and common
sense. For any given soil condition, allow the auger to
dig at the rate most comfortable to the operators
(exercising correct operating positions), yet not causing
the centrifugal clutch to overload and slip.
An improper operating procedure can allow the
auger to "bind" and/or "bury" itself in the hole. This
is usually the result of allowing the auger to feed at
an excessive rate. This phenomenon is also
characteristic of digging with smaller diameter (2 to
4 inch) augers. In this condition, the Hole Digger is
not capable of transmitting ample power to free the
auger. Do not continue to overload and slip the
centrifugal clutch assembly. Excessive heat can be
created by the slippage resulting in clutch
component failure.