Education Pack
OUTSIDE MICROMETERS
Definition
Parallax Error
®
Micrometer for external measurements (EN ISO 3611)
"Measuring instrument which gives the evaluation of a
dimensional quantity of an external feature of a workpiece
on the basis of movement of a spindle with a measuring
face, moving relatively to a material measure and an anvil,
with the movement generated by a screw thread."(1)
Measuring faces
Anvil
Sleeve
Spindle
Look directly at the fiducial line when taking a reading against the thimble graduations. If the graduations are viewed
from an angle, the reading will be incorrect due to parallax error.
Thimble
Spindle clamp
(b)
Frame
(a)
(c)
Sleeve
(a) From above the
fiducial line
Ratchet
Application
(b) Looking directly at
the fiducial line
Thimble
(c) From below the
fiducial line
DIGIMATIC output connector
Measuring Force Control
Display reading HOLD button
ZERO (Incremental mode) / ABS (Absolute mode) setting button
Thermally insulating plate
Origin button (ABS-Zero)
To promote consistent and accurate measurement, it is recommended that the ratchet mechanism is used (if fitted) so
that the measuring force is held constant. Operating the ratchet three times between finger and thumb is sufficient.
IP65 level
Is recommended for shopfloor environment. It has excellent resistance against water and dust enabeling the
micrometer to use in machining situations that include
splashing coolant fluid.
Sleeve
Spindle
Measuring faces
Fiducial line
Anvil
One hand operation with QuantuMike, a ratched thimble
micrometer. This is a micrometer with a 2 mm spindle
pitch, offering movement four times as fast as a standard
micrometer with 0.5 mm spindle pitch.
Frame
Ratched thimble
Fast drive with ratchet stop
Thimble scale
Sleeve scale
Thimble
Fast drive with
ratched
Type
Ratchet stop
Spindle clamp
Ratchet thimble
Thermally insulating plate
Application in a micrometer stand. Keeps both hands free
for operating the micrometer and positioning the
workpiece.
High accuracy micrometer
Enabeling 0.1 µm resolution measurement. This micrometer is ideal for applications like highly accurate measurements with a handheld tool.
One-handed operation
Remarks
Unsuitable
Audible clicking operation causes micro-shocks
Suitable
Audible operation provides
confirmation of constant measuring force
Dedicated Micrometers (Sample Assortment)
Standard
Type
EN ISO 3611
Geometrical product specifications (GPS) – dimensional measuring equipment:
Micrometers for external measurements – design and metrological characteristics
Picture
Application
Remarks
Point micrometer
Extremely high surface pressure
3-8 N measuring force
Carbide or hardened steel tip
Spline micrometer
High surface pressure
5-10 N measuring force
How to Read an Analog Micrometer
Micrometer with standard scale (graduation: 0.01 mm)
(1) Sleeve scale reading 7.00 mm
(2)Thimble scale reading 0.37 mm
(1)
0
5
45
40
35
30
Application IP65 micrometer in a machine tool.
(1)
Micrometer reading Approx. +1 μm
7.37 mm
Approx. +2 μm
(2)
Note:0.37 mm (2) is read from the
thimble scale where it
intersects the fiducial line.
Fiducial line
Thimble line
Fiducial line
Thimble line
The thimble scale can be read directly to 0.01 mm, as shown above, but may also be estimated to 0.001 mm when the
lines are nearly coincident because the line thickness is 1/5 of the spacing between them.
Blade micrometer
High surface pressure
5-10 N measuring force
Non-rotating spindle
Zero setting of analog micrometer
If the error is ≤ ±0.01 mm. Clamp the spindle and use the
key spanner to turn the sleeve with the fiducial line to zero
position of the thimble.
Calibration
For micrometers gauge blocks or
gauge block combinations should be
selected. Refer to EN ISO 3611, the
following gauge blocks are suitiable
for micrometer thread pitches of
0.5 mm and 1 mm.
Block allocation
2.5 mm
15 mm
5.1 mm
17.6 mm
7.7 mm
20.2 mm
10.3 mm
22.8 mm
12.9 mm
25 mm
EN ISO 3611 (2010)
Definition
Electronic digital-indicator gauge (EN ISO 13102)
"Measuring instrument in which the axial displacements
of a plunger are obtained by a transducer and converted
into an electronic signal by suitable electronic means and
transmitted to a physically integrated digital display."(1)
Mechanical dial gauge (dial indicator) (EN ISO 463)
"Measuring instrument in which the axial displacements
of a plunger are transmitted and magnified by suitable
mechanical means to a pointer which rotates in front of
an analogue circular scale.
It may also be provided with a revolution-counting device, e.g. in which a pointer rotates in front of a scale
which indicates the number of revolutions of the pointer
or the axial displacement of the plunger."(2)
Application
DIGIMATIC
output connector
Protection cap
Education Pack
DIGITAL AND DIAL INDICATORS
Standard
Different Dials
EN ISO 13102
Geometrical product specifications (GPS) – dimensional
measuring equipment:
Electronic digital indicator – design and metrological
characteristics.
Scale graduation: 0.01 mm
EN ISO 463
Geometrical product specifications (GPS) – dimensional
measuring equipment:
Dial gauges – design and metrological characteristics.
Spindle Lifting Function
Bi-directional (multi-revolution)
Balanced (multi-revolution)
Balanced (one revolution)
Scale graduation: 0.001 mm
Spindle lifting lever
Spindle lifting knop
Spindle lifting cable
Spindle lifting handle
Display
Data output or
hold button/
on-off button
Parameter setting
e.g. counting direction,
tolerance function
ABS preset (ABS-Zero)/
Zero (incremental mode)
Stem
Mounting an Indicator
Mounting method
Clamping the stem
directly with a screw
Plunger (or spindle)
Example
Standard scale spacing
Double scale spacing
Balanced (multi-revolution)
ore
rm
mo
8m
Tolerance Judgment
Contact element
Measuring face
Clamping the stem
by split-clamp fastening
One Revolution Dial Indicator
Tolerance judgment with pointer
and limit indicators
M6 screw
Plain washer
Scale graduation
Go
Lug mounting
Limit indicator
+NG
Bezel
clamp
Bezel
Multifunction digital indicator in a gauge stand
Tolerance judgment ± NG / GO
red / green LCD backlight
Go
Scale
Dial
+NG
Instructions of Application
Should the workpiece be approx.
1 mm larger than nominal dimension, the part is assessed as good if
the smaller pointer is ignored.
Fault-free identification of rejects.
If the workpiece is appr. 1 mm larger or smaller the pointer goes to
the red area of the dial.
Pointer
Measurement
value and tolerance
judgment
Revolution counting
device
Stem
Plunger (or spindle)
NG
Contact element
Dial indicator with bore gauge measuring inside
diameter
(1)
EN ISO 13102 (2012)
(2)
Measuring face
Okay
Correct mounting: To maintain a minimum measuring circuit
(prevent applied forces), the dial indicator should be clamped as
close as possible to the stand column.
-NG
Go
+NG
-NG
Go
+NG
Enlarged display
of the tolerance
judgment
Calibration
It is recommended to use an
gauge calibration equipment
(I-Checker) with software support. The calibration should
evaluate the performance of the
indicators within the measuring
range using both directions of
displacement of the plunger.
EN ISO 463 (2006)
Education Pack
GAUGE BLOCKS
Definition
Building up a Stack
Gauge blocks are used for setting and calibrating
measuring instruments and are the most important means
for connection to the length unit meter at company level.
They embody a certain length with a high degree of
accuracy – hence the term material measure.
When building up a stack (e.g. 55.826 mm) don’t pick the big blocks
first by working on the first digit. That way is harder and you may
run out of combinations.
Work from right to left by obtaining the last digit first. The last
digit in this case is 6, so pick 1.006 mm. Work through
the rest of the dimension by picking the largest blocks
that fit the next digit(s), as shown.
Advantages of Ceramic Gauge
Blocks
1. Corrosion restistant
Anti-corrosion treatment is not required when handled normally (i.e.
with fingers), resulting in simple maintenance and storage.
2. No burrs caused by dents, ect.
Since the CERA Blocks is very hard, it will not scratch and is highly
resistant to burrs. If a burr is formed, it can easily be removed with a
ceramic deburring stone (Ceraston).
3. Abrasion resistant
CERA Blocks have 10 times the abrasion resistance of steel gauge blocks.
Application
Based on 1 mm steps
1st pick
2nd pick
3rd pick
4th pick
5th pick
6th pick
Total
Completed gauge block
stack 55.826 mm
1.006
1.32
1.5
2
20
30
Material CERA Block
(ZrO2)
1350
Property
Hardness (HV)
Steel
(Fe)
800
Carbide
(WC-Co)
1650
Wear Resistance of Different Materials
50
Abrasion loss
(µm)
Steel
55.826
0.4
Standard
Certificates
EN ISO 3650
Geometrical product specifications (GPS) - length
standards - gauge blocks
ILAC
The International Laboratory Accreditation Cooperation is
an international cooperation of laboratory and inspection
accreditation bodies. The member bodies signed the ILAC
Mutual Recognition Arrangement (MRA) which guarantees a cross approval of certificates from accredited
laboratories from other countries. Signatories to the ILAC
arrangement are almost all European countries.
nominal length
Checking the accuracy of measuring tools
1.8
xxx
xxx
cotton wool
cosmetic brush
ceraston
Wringing Two Thick Gauge Blocks
Step 1
Grade and Application
The grades specify the metrological characteristics (grades of accuracy). The following table can be used to select the
gauge block grade according to usage (specified by EN ISO 3650, BS4311, and JIS B 7506).
Workshop use
Inspection use
Calibration use
Reference use
Applications
• Mounting tools and cutters
• Manufacturing gages
• Calibrating instruments
• Setup of measuring devices
• Checking the accuracy of gages
• Calibrating instruments
• Checking the accuracy of gauge blocks for workshop
• Checking the accuracy of gauge blocks for inspection
• Checking the accuracy of instruments
• Checking the accuracy of gauge blocks for calibration
• For academic research
air blower
microfiber
cloth
JCSS
Mitutoyo gauge block sets can be delivered with a JCSS
certificate of calibration (Japan Calibration Service
System). A JCSS certificate of calibration is comparable
with e.g. DAkkS, COFRAC, RvA or UKAS certificate of
calibration. According to ILAC, this calibration result may
be accepted internationally.
Setup of measuring devices
Calibrating measuring instruments
petroleum
ether
xxxxxx
50
mm
nominal length
Measuring faces
Perfect Wringing of Gauge Blocks
Grade
2
1 or 2
1 or 2
0 or 1
K or 0
K
Bring the two measuring
faces into contact with
each other at right
angles.
Step 2
Tungsten
carbide
0.2
• Wringing should always be performed in a clean place
on a soft pad - if gauge blocks slip from your hand,
they will not be damaged.
• Wipe off the oil film from the gauge blocks using a soft
cloth and petroleum ether.
• After this “rough” cleaning the surfaces are cleaned
with a cosmetic brush rinsed with petroleum ether
and then “blown free” with an air blower.
• Never use alcohol or common benzine for cleaning;
common benzine contains too many impurities and
alcohol always has aqueous components which may
cause corrosion.
• Best-suited for wiping gauge blocks are microfiber
cloths.
• Check the cleaned gauge blocks for rust and scratches.
• If there are any burrs on the measuring surface remove
them carefully using a special ceraston for gauge
blocks. Move the dry gauge block over the ceraston
exerting very low pressure.
• In case the measuring surfaces are in good condition,
but wringing is still difficult, you may wipe them with
medical cotton wool - its oily components will
provide a fine film thus improving the grip of the
measuring surfaces.
CERA Block
0
2000
4000
6000
8000
Amount of travel (m)
4. Dimensionally stable
CERA Blocks are free from dimensional change over time.
5. Sizes clearly marked
Black characters, indicating the nominal length, are inscribed by laser
and are clearly visible against the white surface of the block.
6. Non-magnetic nature prevents steel swarf contamination
7. High wringing force
Superior flatness and surface finish provides maximum wringing force.
8. Closest expansions coefficient to steel
The thermal expansions coefficient of a CERA Block is quite similar to
that of a steel gauge block.
Material CERA Block
Property
(ZrO2)
Coefficient of thermal expansion
9.3 ± 0.5
-6
(10 /K)
Steel
(Fe)
10.8 ± 0.5
This is a clear advantage: The gauge blocks should have a coefficient
close to that of the measuring instrument itself. Otherwise there would
be an error due to different amounts of thermal expansions, e.g. under
workshop conditions.
Temperature Characteristics of Different Materials
Difference in
dimension (µm)
3
2
While applying a small amount of force, gently turn
one gauge block on the other. You will feel the two
blocks stick together.
Slide one gauge block
over the other so that
the sides of the blocks
are flush with each
other.
Tungsten carbide
1
17
18
CERA Block
19
20
-1
Step 3
Carbide
(WC-Co)
5.5 ± 1.0
-2
-3
21
22
23
Temperature (C)
Differences in the dimension between some
materials and steel that are obtained when
measuring testpieces witha length of 100 mm
at each temperature.
9. Highly resistant to dropping and impact
The CERA Block material is one of the toughest ceramics. It is extremly
difficult to crack a CERA block in normal use.