Full Product Manual

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file; the tip of the thumb pointed
forward. For lighter strokes
however, the thumb can be turned
to as much as right angles to the
direction of the stroke
If the file is being used one-handed
for filing pins, dies or edged
tools not being held in a vise, the
forefinger, and not the thumb is
placed on top of the handle in line
with the file.
Carrying the file
For normal flat filing, the operator
should aim to carry the file forward
on an almost straight line in the
same plane, changing its course
enough to prevent grooving. Too
much pressure often results in a
rocking motion causing a rounded
surface.
Keep the file cutting
One of the quickest ways to ruin
a good file is to apply too much
pressure, or too little, on the
forward stroke. Different materials
of course require different touches;
however, in general, just enough
pressure should be applied to keep
the file cutting. If allowed to slide
over the harder metals the teeth of
the file rapidly become dull, and if
they are overloaded by too much
pressure, they are likely to chip
or clog.
On the reverse stroke, it is best to
lift the file clear of the workpiece,
except on very soft metals. Even
then pressure should be very light,
never more than the weight of the
file itself.
Drawfiling consists of grasping
the file firmly at each end and
alternatively pushing and pulling
the file sideways across the work.
Since files are made primarily to
cut on a longitudinal forward stroke,
a file with a short-angle cut should
never be used, as it will score and
scratch instead of shaving and
Shearing. When accomplished
properly, drawfiling produces a
finer finish than straight filing.
Normally, a standard Mill Bastard
file is used for drawfiling, but where
a considerable amount of stock
has to be removed, a Flat or Hand
file (Double Cut) will work faster.
However, this roughing down
leaves small ridges that will
have to be smoothed by finishing
with a Single Cut Mill file.
Lathe filing
When filing work revolving in a
lathe, the file should not be held
rigid or stationary, but stroked
constantly. A slight gliding or lateral
motion assists the file to clear itself
and eliminate ridges and grooves.
While a Mill file is capable of good
lathe filing, there is a special Long
Angle Lathe file with teeth cut at a
much larger angle. This provides a
cleaner shearing, self-clearing file,
eliminates drag or tear, overcomes
chatter and reduces clogging.
Uncut edges on this file protect any
shoulders on the work, which are
not filed, and the dog, which holds
the workpiece.
Lathe filing is usually employed
for fitting shafts. Where stock is
to be removed, a 12"/300mm or
14"/350mm Long Angle Lathe file
is preferable. This file will provide
the finish suitable for a drive fit. For
a running fit a Mill file will provide a
smooth finish. Where
Drawfiling