ALTANA Pencil Hardness Tester - Manual (Page 8)

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coating, moving up the hardness grade scale
until marking occurs over the test distance.
If marking has occurred repeat the test (3.1 to
the 3.8) down the hardness scale until marking
no longer occurs.
3.11 Carry out the test in duplicate, if the results
differ by more than one pencil unit.
Note:.The hardness of the hardest pencil that does
not mark the coating is the so-called pencil
hardness. Further definition of pencil hardness is
stated in the test method standards.
4.0.Limitations
This test method is applicable to smooth surfaces,
it is not considered suitable for textured or rough
surfaces.
5.0.Routine.Maintenance
5.1 Ensure the Pencil Tester body is free from
damage, dents, paint chips etc. as this may
effect the applied mass.
5.2 The rubber rings on the wheels are clean and
free to rotate.
5.3 The instrument and pencils are stored in the
case supplied when not in use. Always
replace any pencils with the same reference
type and manufacturer. (pencils from different
manufacturers may produce different results).
5.4 Ensure the special pencil sharpener supplied
is always used, check the blade for sharpness.
5.5 Replace the abrasive paper 400 grit when
required.
6.0.Calibration
6.1 The Pencil Tester may be checked for the
correct applied mass by preparing the
instrument as defined (6.2 to 6.6)
Note:.The instrument is correctly set at the factory,
no further adjustment can be made.