ASTM D661-93(2005)

Standard Test Method for Evaluating Degree of Cracking of Exterior Paints

SIGNIFICANCE AND USE
Cracking failure of paint films can occur in use. This test method provides a means of evaluating the degree of the failure by comparing the pictorial standards.
SCOPE
1.1 This test method covers the evaluation of the degree of cracking of exterior paints by comparison with photographic standards.

General Information

• Status: Historical
• Publication Date: 31-Aug-2005
• ICS: 87.040 - Paints and varnishes
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.25 - Evaluation of Weathering Effects

Relations

• Replaces: ASTM D661-93(2000) - Standard Test Method for Evaluating Degree of Cracking of Exterior Paints
• Effective Date: 01-Sep-2005
• Replaced By: ASTM D661-93(2011) - Standard Test Method for Evaluating Degree of Cracking of Exterior Paints
• Effective Date: 01-Nov-2011
• Referred By: ASTM D1006/D1006M-21 - Standard Practice for Conducting Exterior Exposure Tests of Hand and Factory Applied Paints on Wood and Wood Composite Materials
• Effective Date: 01-Sep-2005
• Referred By: ASTM D333-01(2021) - Standard Guide for Clear and Pigmented Lacquers
• Effective Date: 01-Sep-2005
• Referred By: ASTM D2065-03(2017) - Standard Test Method for Determination of Edge Performance of Composite Wood Products Under Surfactant Accelerated Moisture Stress
• Effective Date: 01-Sep-2005
• Referred By: ASTM D7254-21 - Standard Specification for Polypropylene (PP) Siding
• Effective Date: 01-Sep-2005
• Referred By: ASTM E1605-22 - Standard Terminology Relating to Lead in Buildings
• Effective Date: 01-Sep-2005
• Referred By: ASTM D5324-16(2022) - Standard Guide for Testing Water-Borne Architectural Coatings
• Effective Date: 01-Sep-2005
• Referred By: ASTM D7856-21 - Standard Specification for Color and Appearance Retention of Solid and Variegated Color Plastic Siding Products using CIELab Color Space
• Effective Date: 01-Sep-2005
• Referred By: ASTM D3451-06(2017) - Standard Guide for Testing Coating Powders and Powder Coatings
• Effective Date: 01-Sep-2005
• Referred By: ASTM D6763-16(2022) - Standard Guide for Testing Exterior Wood Stains and Clear Water Repellents
• Effective Date: 01-Sep-2005
• Referred By: ASTM D5722-20 - Standard Practice for Performing Accelerated Outdoor Weathering of Factory-Coated Embossed Hardboard Using Concentrated Natural Sunlight and a Soak-Freeze-Thaw Procedure
• Effective Date: 01-Sep-2005
• Referred By: ASTM D1014-18 - Standard Practice for Conducting Exterior Exposure Tests of Paints and Coatings on Metal Substrates
• Effective Date: 01-Sep-2005
• Referred By: ASTM D6137-97(2018) - Standard Test Method for Sulfuric Acid Resistance of Polymer Linings for Flue Gas Desulfurization Systems
• Effective Date: 01-Sep-2005
• Referred By: ASTM G210-13(2023) - Standard Practice for Operating the Severe Wastewater Analysis Testing Apparatus
• Effective Date: 01-Sep-2005

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:D661–93(Reapproved2005)
Standard Test Method for
Evaluating Degree of Cracking of Exterior Paints
This standard is issued under the fixed designation D661; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope 5. Types of Cracking
1.1 This test method covers the evaluation of the degree of 5.1 Three types of cracking are recognized:
cracking of exterior paints by comparison with photographic 5.1.1 Irregular Pattern Type—Cracking in which the breaks
standards. in the film are in no definite pattern.
5.1.2 Line Type—Cracking in which the breaks in the film
2. Referenced Documents
are generally arranged in parallel lines, usually either horizon-
2.1 ASTM Standards:
tally or vertically, over the surface of the film. These breaks
D660 Test Method for Evaluating Degree of Checking of often follow the line of brush marks.
Exterior Paints
5.1.3 Sigmoid Type—Cracking in which the breaks in the
2.2 Other Standards: film form a pattern consisting of curves meeting and intersect-
Pictorial Standards of Coating Defects Handbook
ing, usually on a relatively large scale.
3. Terminology 6. Use of Photographic Reference Standards
3.1 Definitions of Terms Specific to This Standard:
6.1 The photographic reference standards that are part of
3.1.1 cracking, n—that phenomenon manifested in paint this test method and are provided in the Pictorial Standards of
films by a break extending through to the surface painted.
Coating Defects Handbook are representative of the degree of
3.1.1.1 Discussion—Where this is difficult to determine, the cracking of exterior paint films. Fig. 1 is for illustration
break should be called a crack only if the underlying surface is
purposes only and should not be used for evaluation.
visible. The use of a magnification of 10 diameters is recom- 6.2 The use of the photographic reference standards illus-
mended in cases where it is difficult to differentiate between trated in Fig. 1 requires the following precautions:
cracking and checking (see Test Method D660).
6.2.1 The accompanying photographic reference standards
show line-type cracking only. Irregular and sigmoid-type
4. Significance and Use
cracking may also be interpreted from these photographs.
4.1 Crackingfailureofpaintfilmscanoccurinuse.Thistest
6.2.2 Care must be taken not to confuse various types of
methodprovidesameansofevaluatingthedegreeofthefailure
failure that may be present on the same surface. This is
by comparing the pictorial standards.
particularly true in observing cracking and checking. Cracking
may very often be an advanced stage of checking and is very
often in evidence along with checking and other failures.
1 6.2.3 It must be realized that the degree of failure will vary
This test method is under the jurisdiction of ASTM Committee D01 on Paint
over any given area. Therefore, an average portion of the film
and Related Coatings, Materials andApplications and is the direct responsibility of
Subcommittee D01.25 on Evaluation of Weathering Effects.
should be used for comparison. On
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