Scratch Hardness Tester LINEARTESTER 249
22
BAE 249
6.3
Double stroke tests
- Crockmeter
Test
- MEK
Test
- Abrasion
Test
- Wipe
Test
Contrary to the single scratch test the guide
plate (15) is not used in these tests, and it can
be dismantled by loosening the two screws with
the help of the enclosed Allen key.
In this way the corresponding test tip rests on
the test panel during all to and fro double
strokes.
The setting of the required cycles is carried out
in the same manner (in the „P“ mode), but
instead of "1" the number is, of course, higher.
In the “C” mode of the display (12) the double
strokes already completed are shown.
To interrupt the test procedure only push the
main switch “EMERGENCY-OFF” (1).
Every new start is also a “Reset” signal for the
cycle counter which is automatically reset
to “0” , whereby in the “P” mode the preset
number of cycles is retained.
The minimum loading that is necessary to cause a close track on the
specimen is used as a measure for the scratch hardness of the
material under test, i.e. if at the first loading no scratch can be
observed, the loading must be gradually increased. If at the first
loading a deep track is already visible, the loading must be gradually
reduced.
To avoid possible damage to the test tool it is advisable to lift the
balance beam slightly whilst shifting the weight or levelling the beam.
Only start the test procedure in the „C“
mode, because otherwise the controller
does not switch off the instrument after the
completion of the preset number of cycles.