Cutterhead Cylinder To Bottom Blade Adjustment - Toro 650D Operator's Manual

MAINTENANCE
1.59 1.59

CUTTERHEAD CYLINDER TO BOTTOM BLADE ADJUSTMENT

IMPORTANT : PREVENT DAMAGE - It is essential that the
relationship between the bottom blades and the cutting cylinders is
kept in good adjustment in order to ensure good cutting performance,
minimum power consumption and prolonged life for the cutting edges.
Carry out the following procedure before commencing work and re-check
the settings every few hours.
0
90
Check that the cutting cylinder is correctly set to the bottom blade by
holding a thin piece of paper between the cutting cylinder and the bottom
blade as shown. Carefully rotate the cylinder as shown and check that the
paper is cut cleanly at all points along the length of the blade. Hold the
paper at 90 degrees (right angles) to the bottom blade to obtain the correct
cutting action.
WARNING: PREVENT ACCIDENTS - Ensure that people are clear
of the cutting cylinders as rotation of one may cause others to rotate.
If adjustment is necessary proceed as follows;
B
Release nut 'A' 1/4 turn both ends.
Turn handwheel 'B' each end alternately whilst rotating the cutting
cylinder backwards until the bottom blade is in 'fleeting' contact with the
A
cylinder along its entire length. Re-check the cutting action along the
length of the bottom blade using a thin piece of paper making marginal
adjustments as necessary.
Tighten nut 'A' both ends.
If it is impossible to obtain a good clean paper cut across the entire length of the bottom blade it will
be necessary to carry out the backlapping procedure to reprocess the cutting edges. In severe cases it
will be necessary to regrind the cutting cylinder and the bottom blade, refer - BACKLAPPING /
GRINDING.
Do not be tempted to over adjust, thus causing heavy contact between the cylinder and bottom blade,
as this will cause very rapid uneven wear to take place leading to tramlining and waviness of the cut-
ting edges. The frictional losses will be high and a significant amount of power will be absorbed, thus
reducing the power available for cutting. The heating effect due to friction will cause excessive expan-
sion to take place which will further aggravate the situation by increasing the contact pressure.
If the cutterheads are allowed to operate for more than a few hours without adjustment the running wear
will eventually cause the cylinder to run out of contact with the bottom blade. At this stage very rapid
rounding of the cutting edges will occur as grass and abrasive particles pass through the
clearance between the blades.
Lack of attention to adjustment can therefore be foolhardy as maintenance costs will escalate. The qual-
ity of cut will also be seriously affected as will the health and growth of the grass.
An experienced operator will notice when a cutterhead starts to go out of adjustment; when the grass
ceases to be cut cleanly and the cut ends become ragged.
111-1033TH051006