2
V7419
(0-6”)
603-198
(0-150mm)
603-205
Reading the scale
Imperial version
Major divisions
= 6 x 0.1”
= 0.6”
Minor divisions
= 1 x 0.025”
= 0.025”
Thimble divisions = 15 x 0.001”
= 0.015”
Reading
= 0.640”
The sleeve is marked with Major divisions representing 0.1” and Minor
divisions representing 0.025”. The thimble is divided into twenty-five
parts around its bevelled circumference, each division represents
0.001”.
Note: Reading indicated is that portion of the sleeve covered by the
thimble.
Metric version
Major divisions
= 16 x 1mm
= 16.00mm
Minor divisions
= 1 x 0.5mm
= 0.5mm
Thimble divisions = 25 x 0.01mm
= 0.25mm
Reading
= 16.75mm
The sleeve is marked with Major divisions representing 1.0mm and
Minor divisions representing 0.5mm. The Thimble is divided into fifty
parts around its bevelled circumference, each division representing
0.01mm.
Note:
Reading indicated is that portion of the sleeve covered by the
Thimble.
Measurement method
1. Remove the thimble/ratchet stop cap and clean the reference ‘seat’
before inserting the measuring rod. Ensure that the rod is placed
correctly, and replace the cap. Do not overtighten.
2. Clean the rod and base reference surfaces and the workpiece to be
measured.
3. Check the accuracy of the depth gauge micrometer using the
calibration and adjustment procedure - detailed overleaf.
4. Hold the base firmly onto a smooth, flat surface above the slot or
recess to be measured and advance the rod until it contacts the
bottom of the hole. Use the ratchet stop to ensure a constant force
and consistent readings.
5. Applying the locking clamp before removing the instrument from the
workpiece. read off the measurement taken using the reading the
scale procedure.
Note:
When obtaining a reading using a rod other than the 0-1”/0-
25mm rod, remember to consider the additional rod length. For
example, if the 3-4”/75-100mm rod is used then 3”/75mm must
be added to the reading shown on the micrometer head sleeve
and thimble.
Calibration and adjustment
The RS depth gauge micrometer should always be checked for
accuracy before use, using the following procedures:
1. When the 0-1”/0-25mm rod is used, clean the instrument base and
rod reference surfaces and retract the rod into the base.
2. Hold the base firmly against a datum surface, i.e. RS surface plate
and advance the rod until it contacts the datum. apply a constant
force with the ratchet stop. If the depth gauge micrometer is adjusted
correctly it should read “zero”.
Note: Other rods can be tested for accuracy by placing a suitable
gauge block onto the datum, setting the instrument base onto
the gauge block and advancing the rod, as above.
3. If an error is indicated, i.e. the zero on the thimble is not aligned with
the index line on the sleeve, this is normally due to wear and
compensation can be made by rotating the “split nut” fitted to each
rod, using the spanner supplied.
4. Should excessive “play” be apparent in the spindle (caused by wear
on the micrometer screw) rotate the thimble back to reveal and
adjustment nut. Using the adjustment spanner provided, tighten the
nut just enough to eliminate the “play”.
Care and maintenance
The RS depth gauge micrometer is a precision instrument, and the care
it needs requires little effort to ensure a long and accurate life.
1. The instrument should be wiped clean of dust and oil before and
after use. Use lint free cleaning cloths or pads. Never use an air hose
as this can force dirt and grit into the spindle threads.
2. Keep the instrument on a clean surface during use.
3. Always return the depth gauge micrometer to its protective storage
box after use.
4. Do not retract or advance the measuring rod by spinning the base
around the axis of the measurement rod.
5. Do not drop the instrument, as this will cause misalignment of the
measuring rod face.
6. Regularly apply a little instrument oil to the screw threads to assure
free running performance.
Note: The set of measuring rods supplied with each RS depth gauge
micrometer have been calibrated specifically for that
instrument. Transposing measuring rods from other sets will
result in inaccurate measurements.
RS Components shall not be liable for any liability or loss of any nature (howsoever
caused and whether or not due to RS Components’ negligence) which may result
from the use of any information provided in RS technical literature.
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RS
Stock No.
