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TO ENSURE HIGH ACCURACY.
When operating a machining centre, the accuracy of the finished product
cannot be maintained unless the following points are observed when operating
the machine. Failure to observe these points can also cause accidents.
Check Points
When clamping a workpiece on the table or in the fixture, take note of
the rigidity of the workpiece.
Make sure that the workpiece will not be loosened or distorted due to
the clamping force.
If any chips are entangled on the workpiece or cutting tool, surface
roughness will be deteriorated. Select a cutting tool which will not
entangle chips.
When starting work and prior to machining, warm up the spindle and
each controlled axis. This will minimize the influence of thermal
displacement on workpiece accuracy.
Workpiece materials and shapes vary widely among machine users.
Select the cutting conditions best suited to each workpiece in order to
obtain the required accuracy. If the selected conditions are not the best
conditions, an accident may occur.
When forged or cast workpieces are used, the cutting allowance with
respect to the finished dimensions varies greatly. Either write a
program which takes the variation into consideration or perform pre-
machining so that a uniform cutting allowance is left on the workpiece.
Perform periodic leveling of the machine as described in the
Maintenance Manual
