adjustment nut. It is this load spring adjustment that
is used to standardize the reading to agree with that
of the standard sample furnished with all models. If
a reading taken on the standard sample does not
agree with the number stamped on it, the load spring
should be adjusted so that the reading obtained will
be the same as marked on the standard sample.
MAKING THE TEST
Each model is provided with a round anvil to facili-
tate testing of tubes, shapes or formed parts as well
as sheet and strip. In checking tapered sections
such as are found in some extrusions, the tester
should be applied in such a way that the anvil bears
along a line which is parallel to the surface in contact
with the penetrator. The right and wrong way of
checking such sections is shown in Fig. 4 page 7.
On at work such as sheet and strip no special
instruction is necessary as the metal to be tested is
simply inserted between the anvil and pene-trator.
Pressure is applied to the handles until “bottom” is
felt and the dial reading taken.
DISASSEMBLY
The entire tester can be taken apart for inspection
or repair by removing the pivot screw and
FIG. 3 Adjusting load on load spring
withdrawing the handle. The penetrator assem-
bly should be held downward with the thumb to
facilitate removal of the handle. After the handle is
removed the entire penetrator assembly is easily
lifted from the frame. The dial indicator may then
be lifted from the housing and the load spring ad-
justing nut backed off and removed with the spe-
cial wrench provided. This will relieve the load on
the spring and permit both spring and penetrator to
be removed. The return spring will be found in the
hole provided for it in the frame and the housing
key is easily detached from the housing.
The dial indicator should not be taken apart unless
an experienced instrument repair technician is
available. Dial indicators in need of repair should
be returned to the address shown in this manual to
insure that repair work will be properly done.
FIG. 4 Making the test
SPECIAL INSTRUCTIONS FOR
THE WEBSTER
®
MODEL B TESTER
The Model B Tester has a single point penetrator
which can be identied from Fig. 5. The dial
indicator is graduated I to 20 and the hardness
readings obtained can be compared to other
hardness readings such as Rockwell and Brinell.
As in all models the amount of load exerted on
the penetrator is determined solely by load spring
adjustment and is not affected by excess handle
pressure.
The handle pressure required to operate the
Model B Tester is the lightest of any of the
three models. This tester is designed for use on
aluminum and its alloys but may also be used for
other metals in that hardness range.
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