From page 24
the plough is lowered, and
this is achieved by adjusting
the central bottle-screw of the
three-point linkage, called the
top-link. To do this, park the
tractor on level ground and
gently lower the plough.
Watch the tips of the
ploughshares carefully as they
reach the ground and adjust
the bottle screw inwards or
outwards until you are
satisfied that the shares meet
the ground at the same time.
The shares are made level by
adjusting the length of the toplink (arrowed).
Now, here's a tip: In the field
the hydraulics actually lower
the plough in an arc, so that
although you have adjusted
the share to an equal height
on ground that is level with
the tractor wheels, as soon as
you lower the plough further
(ie 10-15cm into the ground)
the rearmost shares will, in
the downward arc of travel,
actually be lower than the
front one, by a fraction. To
overcome this, once you are
satisfied that the shares are
level on flat ground, screw the
bottle screw in a fraction, to
tweak the rear shares up a
little, just to compensate for
the arc effect.
Up to this stage, all your
adjustments have been made
on flat level ground. This is
not the reality in the field,
however, when your tractor is
(or should) be working at an
angle, the right hand wheels
being in the left-most furrow
of the previous pass of the
IN THE FIELD
plough. This can exaggerate
the angle of the plough share
and mess up your ability to
neatly and accurately throw
the soil. It will also mean that
the left-hand (front) share is
now deeper than its counterparts behind and some
adjustment by way of the
levelling box (on the right
hand arm of the three point
lift) will be necessary to
ensure that the two (or three
as the case may be) furrows
formed by the shares are of
the same depth.
Finally, the proof of the
ploughing is in the viewing (to
mix a metaphor). After a
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couple of passes up and
down the field stop the
tractor and examine the
furrows and the throws from
each pass. Then furrows
should be straight and level in
depth, both over the full
length of the field and in
relation to one another and, if
your field was flat to begin
with, the furrows should each
be filled with equal quantities
of upended soil from
subsequent passes. If either of
these criteria is not being
achieved, adjust the level,
angle and height of the
plough in the field before
continuing.