Elcometer 121/2 User manual

English
Elcometer 121/2
Universal Paint Inspection Gauge
Operating Instructions

English
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is a registered trademark of Elcometer Ltd.
All other trademarks acknowledged.
© Elcometer Ltd. England 1994 - 2008.
All rights reserved. No part of this document may be reproduced, transmitted, transcribed, stored (in a retrieval
system or otherwise) or translated into any other language in any form or by means (electronic, mechanical,
magnetic, optical, manual or otherwise) without the prior written permission of Elcometer Ltd.
A copy of this Instruction Manual is available for download on our Website via
www.elcometer.com/downloads
Doc. No:TMA-0151 Iss. 04
Part No: 4811
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CONTENTS
Section Page
1 About your gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2 Getting started. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3 Mounting and changing tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4 Measuring film thickness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
5 Measuring cross-cut adhesion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
6 Measuring indentation hardness (Buchholz) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
7 Spare parts and accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
8 Fault checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
9 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
10 Related equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

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Thank you for your purchase of this Elcometer 121/2 Universal P.I.G. Welcome to Elcometer.
Elcometer are world leaders in the design, manufacture and supply of inspection equipment for coatings
and concrete. Our products cover all aspects of coating inspection, from development through application
to post application inspection.
The Elcometer 121/2 Universal P.I.G. is a world beating product. With the purchase of this instrument you
now have access to the worldwide service and support network of Elcometer. For more information visit our
website at www.elcometer.com
1 ABOUT YOUR GAUGE
The Elcometer 121/2 Universal P.I.G. (Paint Inspection Gauge) offers a quick, versatile method of coating
examination and measurement in a portable, easy-to-use gauge. The gauge allows the following tests to be
conducted:
• Coating thickness
• Cross cut adhesion (using optional accessories)
• Buchholz hardness (using optional accessories)
All test tools are mounted on a rotary head within the body of the gauge, allowing rapid change over from
one test to the next.
The gauge includes a built in 50x microscope with graticule scale and illumination. The gauge body is
manufactured from aluminium.

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1.1 STANDARDS
The Elcometer 121/2 Paint Inspection Gauge can be used in accordance with the following National and
International Standards:
ASTM D 4138 ASTM D 3359-B BS EN 3900-CS-5B BS EN ISO 2815
DIN 53151 DIN 53153 ISO 2808-5B ISO 2409
1.2 WHAT THE BOX CONTAINS
• Elcometer 121/2 Universal P.I.G. with metric scale
• Cutters No. 1, 2 and 3, fitted and ready to use
• Hexagonal wrench 1.5 mm
• Hexagonal wrench 2.5 mm
• Marker pen
• Spare bulb (lens bulb 1.2 V; 0.2 A)
• Spare battery (Mignon leak proof 1.5 V)
• Carrying case
• Operating instructions
The instrument is packed in a cardboard and foam package. Please ensure that this packaging is disposed
of in an environmentally sensitive manner. Consult your local Environmental Authority for further guidance.
To maximise the benefits of your new instrument, please take some time to read these Operating
Instructions. Do not hesitate to contact Elcometer or your Elcometer supplier if you have any
questions.

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2 GETTING STARTED
2.1 FITTING BATTERIES
The Elcometer 121/2 Universal P.I.G. uses dry cell batteries only.
To fit or replace the battery: Use a coin to loosen and open the slotted screw beside the eye-piece. Remove
battery and replace with new battery 1.5 V (leakproof), positive end first. Reclose in reverse order.
Note: Remove the batteries from the instrument if it is to remain unused for a long period of time. This will
prevent damage to the instrument in the event of malfunction of the batteries.
Batteries must be disposed of carefully to avoid environmental contamination. Please consult your local
Environmental Authority for information on disposal in your region.
Do not dispose of any batteries in fire.
2.2 REPLACING THE BULB
Screw objective lens into the instrument until the bulb is easily accessible. Loosen bulb holder slightly with
small hexagonal wrench and screw out the bulb. Screw in the spare bulb (1.2 V, 0.22 A) and re-secure the
bulb holder.
Check Light Spot: To do this, place the PIG in measuring position over a textured object (for example, a
newspaper) and switch the light on. The light spot, with its maximum brightness, must lie below the centre
of the objective lens. If not, loosen the bulb holder with the hexagonal wrench and move it until the light spot
is correctly placed. Then secure the holder.

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3 MOUNTING AND CHANGING TOOLS
All tools are mounted onto the rotary head:
1. Cutting Tool No. 1
2. Cutting Tool No. 2
3. Cutting Tool No. 3
4. Cross hatch cutter
5. Cross hatch cutter
6. Buchholz Indentation Tool
3.1 MOUNTING THE TOOLS
C
UTTING T OOLS : Positions 1, 2 and 3. These are located in slots
in the rotary head by means of hexagonal screws (large
hexagonal wrench M 2.5). For inserting or replacing, loosen
applicable screw, let cutter protrude approximately 3 mm from the rotary head and re-tighten screw.
C
ROSS C UT K NIVES : Positions 4 and 5. These are located by means of two hexagonal screws each (small
hexagonal wrench M 1.5) laterally from the receptacle slots of the rotary head. The tools have holes, which
ensure firm seating. When only one knife is to be changed, the screws of all tools from No. 4 to No. 6 must
be loosened, otherwise the slot can become too narrow due to distortion of the rotary head.
Note: Re-tighten all screws after insertion of, or replacement of, any knife.
B
UCHHOLZ I NDENTATION T OOL : Mount the Buchholz indentation tool in Position 6. The tool is mounted in the
same manner as the Cross cut knives - refer to paragraph above for instructions.

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3.2 CHANGING TOOLS
When changing from one cutter to another, first press the ‘Stop’ knob against the casing. Then turn the
rotary head to the desired position and lock it by releasing the ‘Stop’ knob.
Note: Care must be taken that the ‘Stop’ knob distinctly and audibly snaps into place.

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4 MEASURING FILM THICKNESS
1. Mark the surface to be tested with a stroke of the black
marker pen provided with your gauge. There should always
be a distinct contrast between the colour of the pen ink and
the coating. Different pen ink colours may therefore be
required.
2. Cut the coating at right-angles to the pen mark as follows:
Place the gauge on the specimen (an exact vertical cut
without tilting the knife is ensured by the supporting feet
beside the push button switch).
Pull the gauge towards you and apply a little pressure.
Slight pressure is normally sufficient to penetrate through to
the substrate. Heavier pressure may be required for very
thick coatings and very hard surfaces.
3. Position the gauge so that the microscope lens is over the
cut with the feet touching the surface.
4. Press and hold the light switch to illuminate the cut.
5. Focus the microscope until the cut is clearly visible.
6. Align the graticule scale at right-angles to the cut so that
the scale divisions are parallel to the cut. Note that one side
of the cut will have a straight edge and the other side is
likely to be ragged.
0
20
18
16
14
12
108642
Exposed
substrate Cut coating
Coating
(uncut)
Count number of graticule divisions
Pen
mark

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7. Measure the width of the cut coating (or coatings) by counting the number of graticule divisions.
To convert the width of the cut coating into coating thickness, multiply the number of graticule divisions by
the resolution given below.
8. In the example given in above, with a No. 3 cutter, the coating thickness is:
34 divisions x 2 = 68 microns, or 34 divisions x 0.08 = 2.7 mils
4.1 MEASURING MULTI-LAYER COATINGS
The thickness of individual layers can be calculated by
measuring each layer.
4.2 IRREGULARITIES
Irregularities can occur if very hard, brittle films, or films with
insufficient adhesion to the substrate are tested. The following
can arise and can be avoided as follows.
Cutter No. Resolution of graticule Maximum thickness Cutting angle
(microns) (mils) (microns) (degrees)
1 20 0.8 2000 45
2 10 0.4 1000 26.6
3 2 0.08 200 5.7
0
20
18
16
14
12
108642

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IRREGULAR, SHELL-LIKE CUT
Draw a straight line through the best estimate of the centre of the
irregular cut edge using the graticule scale. This will give a mean
value for thickness.
POOR ADHESION (GIVES THE ILLUSION OF TOO LITTLE
FILM THICKNESS)
Despite the fact that the coating may have fractured at point ‘x’,
always measure distance ‘A’ to obtain the thickness of the
coating (single layer of coating in this example).
NO SEPARATION
When measuring the thickness of clear varnish on wood, there
may be no visible demarcation between the coating and the
substrate. If this is the case, soak the exposed wood grain with
a dye solution (fountain pen ink). The coating will not absorb any
dye, but the wood cells do. This enables the cut width to be
measured.
Cutter knife
substrate
coating
A
x
Cutter knife
wood substrate
coating

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5 MEASURING CROSS-CUT ADHESION
The cross hatch cutter scores through the coating right down to the next coating layer or down to the
substrate. Two cuts are made at right angles to each other resulting in a grid of small squares. Adhesion is
then assessed visually by comparing the grid of squares against ISO, ASTM or Corporate Standards.
5.1 SELECTING CUTTING BLADES
A range of cutting blades is available for different thicknesses and types of coating.
Mount the cutting blades in positions 4 and 5.
5.2 ANALYSING THE RESULTS
Assess the coating adhesion by comparing the lattice of cuts with ISO, ASTM or Corporate Standards. ISO
and ASTM standards are reproduced in Table 1
Cutter no. Multi-cut tool Cut interval
(mm) Use for film thickness up to (µm) No. of cutters
T12112185 DIN 53 151 1 up to 60 6
T12112186 DIN 53 151 2 60 to 120 6
T12112183 ASTM D3359-B 1.0 US cross cut 11
T12112184 ASTM D3359-B 1.5 US cross cut 11

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.
Table 1: Cross-Cut Adhesion - Classification of Test Results
Surface Description ISO ASTM
The edges of the cuts are completely smooth; none of the squares of the
lattice is detached.
0 5B
Detachment of flakes of the coating at the intersections of the cuts. A
cross cut area not significantly greater than 5% is affected.
1 4B
The coating has flaked along the edges and/or at the intersections of the
cuts. A cross cut area significantly greater than 5%, but not significantly
greater than 15% is affected.
2 3B
The coating has flaked along the edges of the cuts partly or wholly in
large ribbons, and/or it has flaked partly or wholly on different parts of the
squares. A cross cut area significantly greater than 15%, but not
significantly greater than 35%, is affected.
3 2B
The coating has flaked along the edges of the cuts in large ribbons and/or
some squares have detached partly or wholly. A cross cut area
significantly greater than 35%, but not significantly greater than 65%, is
affected.
4 1B
Any degree of flaking that cannot be classified even by classification 4
(1B).
5 0B

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6 MEASURING INDENTATION HARDNESS (BUCHHOLZ)
This test is carried out with the Indenting Tool (tool No. 6) in conjunction with the slip-on weight, and in
accordance with DIN 53 153. The indenting tool incorporates a disc which has a sharp bevelled edge.
Pressure between the disc and the coating results in an indentation being formed in the coating.
Measurement of the dimensions of the indentation reveals the indentation hardness of the coating.
1. Turn the rotary head to position 6.
2. Place the slip-on weight onto the PIG.
3. Place the PIG onto the surface to be tested with the indentation tool in contact with the test area.
4. Leave the PIG for 30 seconds (timed using a stopwatch) and then lift the PIG carefully away from the
surface.
5. Remove the weight.
6. Position the PIG so that the microscope lens is over the indentation with the feet touching the surface.
7. Press and hold the light switch to illuminate the indentation.
8. Focus the microscope until the indentation is clearly visible.
9. Align the graticule scale at right-angles to the indentation so that the scale divisions are parallel to the
indentation.
10. Measure and record the length of the indentation in the coating by counting the number of graticule
divisions.
The length of the indentation is inversely proportional to the hardness of the coating; use Table 2 to
determine the indentation resistance and depth

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.
Table 2: Buchholz indentation - Classification of test results
Indentation length Indentation
resistance
Indentation depth Minimum coating thickness for which
a measurement is valid
(mm) (µm) (mils) (µm) (mils)
0.8 125 5 0.2 15 0.59
0.85 118 6 0.24 20 0.79
0.9 111 7 0.28 20 0.79
0.95 105 7 0.28 20 0.79
1.0 100 8 0.31 20 0.79
1.05 95 9 0.35 20 0.79
1.1 91 10 0.39 20 0.79
1.15 87 11 0.43 25 1
1.2 83 12 0.47 25 1
1.3 77 14 0.55 25 1
1.4 71 16 0.63 30 1.18
1.5 67 18 0.71 30 1.18
1.6 63 21 0.83 35 1.38
1.7 59 24 0.94 35 1.38

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7 SPARE PARTS AND ACCESSORIES
The following spare and optional items are available from Elcometer, or your local supplier.
Cutter No. 1, 20 µm to 2000 µm (0.8 mils to 70 mils) T12112191
Cutter No. 2, 10 µm to 1000 µm (0.4 mils to 40 mils) T12112192
Cutter No. 3, 2 µm to 200 µm (0.08 mils to 8 mils) T12112193
Cross hatch cutter, 1 mm (ISO/DIN) T12112185
Cross hatch cutter, 2 mm (ISO/DIN) T12112186
Cross hatch cutter, 1 mm (ASTM) T12112183
Cross hatch cutter, 1.5mm (ASTM) T12112184
Buchholz Indentation Tool No. 6 T12112187
Buchholz Slip-on Weight, 500 g T12112188

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8 FAULT CHECKLIST
Fault Cause Corrective Action
Bulb does not illuminate Battery flat Insert new batteries
Bulb defective Insert new bulb
Poor contact Remove slotted screw and scratch upper surface of
battery casing vigorously with coin until oxidated
metal is bare again
Break in circuit Return the gauge to your Elcometer supplier
Battery cannot be removed Unsuitable, non leakproof
battery used
Return the gauge to your Elcometer supplier
All cuts are rough and ragged Point of cutter tool damaged Replace tool
Cross cuts are irregular Cross cutter worn out Replace tool
Scale of measuring
microscope blurred
Graticule scale holder loose Return the gauge to your Elcometer supplier
Illumination of measuring
point not adequate
Bulb misaligned Re-adjust bulb holder See “Replacing the bulb” on
page 4

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9 MAINTENANCE
The Elcometer 121/2 Universal P.I.G. is designed to give many years reliable service under normal
operating and storage conditions.
The instrument does not contain any user-serviceable components. In the unlikely event of a fault, the
instrument should be returned to your local Elcometer supplier or directly to Elcometer. Contact details can
be found on the outside cover of these instructions, or on the Elcometer website, www.elcometer.com
10 RELATED EQUIPMENT
In addition to the Elcometer 121/2 Universal P.I.G., Elcometer produces a wide range of other equipment
for testing and measuring the characteristics of coatings. Users of the Elcometer 121/2 may also benefit
from the following Elcometer products:
• Elcometer 141 Paint Inspection Gauge (for deeper cuts)
• Elcometer 107 Cross Hatch Cutter
• Elcometer 195 Säberg Drill
• Elcometer 456 Coating Thickness Gauge
• Elcometer Coating Adhesion Testers
For further information contact Elcometer, your local supplier or visit our website at www.elcometer.com