ASTM D1212-91

Standard Test Methods for Measurement of Wet Film Thickness of Organic Coatings

General Information

• Status: Historical
• Publication Date: 31-Dec-1990
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.23 - Physical Properties of Applied Paint Films

Standards Content (Sample)

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~~l~ Designation: D 1212- 91
- -1916 Race St _Phita.detPhia., .Pa.<1 940_3··
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
If not listed In the current combined index, will appear in the next edition.
Standard Test Methods for
1
Measurement of Wet Film Thickness of Organic Coatings
This standard is issued under the fixed designation D 1212; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year oflast revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (E) indicates an editorial change since the last revision or reapproval.
I. Scope mine wet film thickness during application can provide the
opportunity to correct the application procedures.
l.l These test methods cover the determination of wet
TEST METHOD A
film thickness of organic coatings such as paint, varnish, and
lacquer. Two methods are described as follows: 5. Apparatus
l.l.l In Test Method A, the Wet Film Thickness Gage
5.1 Wet Film Thickness Gage'-Two versions of the gage
(English or Metric graduation (see 5.1)) is used to measure 4
are now in use : The original design as shown in Fig. l and a
wet film thicknesses up to 60 mils on the English scale series,
as shown in Fig. 2. Both designs consists of an
later design
and up to 700 11m on the metric scale series (Sections 5
eccentric center wheel supported by two concentric wheels so
8).
through
as to provide two scales that are bilaterally symmetrical. As
1.1.2 In Test Method B, the Pfund Gage is used to
the gage is rolled on the film, there is a change in clearance
measure wet film thicknesses up to 14.2 mils (360 11m)
between the wet film and the eccentric wheel. The point at
(Sections 9 through 13).
which the film first touches the center wheel measures the
1.2 This standard does not purport to address if any, the
thickness of the film.
safety problems associated with its use. It is the responsibility
5.2 The later design shown in Fig. 2, moves the eccentric
of whoever uses this standard to consult and establish
wheel from between the concentric wheels, as shown in Fig.
appropriate safety and health practices and determine the
l, to the outside of the gage and closer to one of the
applicability of regulatory limitations prior to use.
concentric wheels. Gage reading errors of parallax across the
gage are eliminated as the two scales are placed directly on
2. Referenced Document
the eccentric wheel and errors when measuring on uneven
2.1 ASTM Standard: support surfaces are reduced by placing the eccentric wheel
D 823 Test Methods for Producing Films of Uniform closer to one of the supporting concentric wheels.
Thickness of Paint, V amish, and Related Products on 5. 3 Best precision is obtained when using the near linear
2
Test Panels central portion of each scale, constituting about 80 % of its
total range as shown in the diagram in Figs. l and 2.
3. Summary of Test Methods
Therefore, the range of the particular gage selected for use
should be such that the measured film thickness falls within,
3.1 The material is applied in the laboratory to plane,
and preferably toward the center of the middle 80 % of each
rigid test panels or in the field to the surface being coated.
scale. Gages are available covering the following ranges in
The wet film thickness is determined as quickly as possible to
mils and microns:
reduce shrinkage due to solvent loss.
3.2 In Test Method A, a gage with one eccentric and two
Smallest
Range, mils Graduation, mils
concentric wheels is rolled over the surface and the point
0 to 2
where the eccentric wheel first touches the wet film is 0.1
0 to 4 0.2
determined.
2 to 12
0.5
3.3 In Test Method B, a gage with a convex lower surface
10 to 30 1.0
is pushed into the wet film until the center touches the 20 to 60 2.0
substrate. The diameter of the spot of wet coating left on the
Smallest
Range, ).lm Graduation, ).lffi
convex surface is measured and the film thickness calculated
0 to 40
from the diameter of the spot and the radius of curvature. 2.0
0 to 100 5.00
50 to 250 10.00
4. Significance and Use
200 to 700
25.00
4.1 Wet film thickness measurements aid in the predic­
tion of dry film thickness. In instances where dry film
3 Available from BYK·Gardner, Inc., Gardner Laboratory, 2435 Linden Ln.,
thickness cannot be measured nondestructively, wet fllm
Silver Spring, MD 20910 and from the Paul N. Gardner Company, Inc., 316 N.E.
thickness is frequently specified. Also, the ability to deter-
First Street, Pompano, FL 33060.
4
Both versions of this gage (lnterchemical (INMOT) and Model "C"), available
from BYK·Gardner, Inc., are covered by U.S. Patents 2 507 592 and 3 128 558,
1
These test methods are under the jurisdiction of ASTM Committee D-1 on and are held by Maynard R. Euverard, 113 Angall Town Ln., Will
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