Jet J-F225, Owner'S Manual

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15
Troubleshooting Blade and Cutting Problems
Problem Probable Cause Solution
Teeth breaking
Incorrect lubricant/coolant fluid Ensure proper coolant flow.
Material too hard
Check the cutting speed, feed speed and air pressure
parameters and the type of blade you are using.
Disc not worn--in correctly
With a new blade it is necessary to start cutting at half
feeding speed. After the wearing--in period (a cutting
surface of about 300 cm
2
for hard materials and about
1000 cm
2
for soft materials) the cutting and feed
speeds can be brought up to normal values
Disc with excessively fine
tooth pitch The swarf wedges into the bottom of the teeth causing
excessive pressure on the teeth themselves
New blade inserted in a
partially completed cut
The surface of the cut may have undergone work
hardening. When starting work again, use a lower
cutting speed and head feed speed. A tooth from the
old blade may be left in the cut: check and remove
before starting work again.
Work piece not clamped firmly
in place
Any movement of the work piece during cutting can
cause broken teeth: check the vise, jaws and clamping
pressure.
Rapid tooth wear
Feed speed too slow
The blade runs over the material without removing it:
increase feed speed.
Cutting pressure too high Reduce cutting pressure.
Blade speed too high
The teeth slide over the material without cutting it:
reduce the blade speed.
Insufficient coolant
Check the coolant level and clean coolant lines and
nozzles.
Incorrect fluid concentration Check and use the correct concentration.
Material defective
The materials may present altered zones either on the
surface, such as oxides or sand, or in section, such as
under-cooled inclusions. These zones, which are
much harder than the blade, cause the teeth to break:
discard or clean these materials.
Broken blade
Feed speed too high Reduce blade speed.
Teeth in contact with material
before starting the cut Always check the position of the blade before starting
a new job.
Insufficient coolant
Check the coolant level and clean coolant lines and
nozzles.
Spindle motor will not
turn
Electrical power supply
Check: the cables, plug and socket. Also check that
the motor connections are in place.
Transformer
Check that the voltages are present both on the input
and output. Otherwise replace.
Contactor
Check that the phases in it are present both on the
input and output, that it is not jammed, that it closes
when powered and that it is not causing short circuits.
Change if any of these problems are found.
Thermal relay
Make sure it is closed, ie check that the phases are
present in input and output that it is not causing short
circuits and responds when the reset coil is closed. If it
has tripped to protect the motor, check the amperage
setting, reset, and check the motor. Change if
necessary.
Motor
Check that it has not burnt out, that it turns freely and
that there is no moisture in the connection terminal
board box. The winding can be rewound or replaced.