METHOD 4061.3
March 22, 2001
21°C and 28°C and the relative humidity shall be 50 ± 5 percent. If the time of drying is not within
the specified limits of the product specification, repeat the test under the atmospheric conditions
specified in 4.2.2.
4.2.2 Referee testing. In case of dispute or disagreement between laboratories, air-drying shall be
done in an atmosphere of 50 ± 4 percent relative humidity and at a temperature of 23°C ± 1°C.
4.2.3 Baking. Baking shall be done in a forced draft laboratory baking oven capable of
maintaining the specified temperature within a range of ± 2°C. The product specification shall
specify the specific temperature for the product.
4.3 Procedure.
4.3.1 Preparation of test specimens.
4.3.1.1 Specimens. All test specimens shall be prepared in duplicate and tested by an operator
properly skilled in the methods to be used.
4.3.1.2 Materials. The materials to be tested shall be applied on clean glass panels or on another
specific substrate of suitable dimension. The coated panels shall be placed in a horizontal position
and shall be shielded from excessive dust accumulation while drying. Ground glass plates are more
suitable for coatings that tend to crawl, such as low viscosity drying oils. Suitable plates can be
prepared by roughening the surface of polished glass by grinding a paste of silicone carbide
(Grit 1-F) and water between two glass plates.
4.3.1.3 Film. The test film preferably shall be cast with a doctor blade having a clearance
sufficient to give the recommended dry film thickness in table I. The allowable dry film thickness
variation obtained with the blade shall not lie outside the limit of 0.1 mils over the area of the film
to be tested. When a suitable doctor blade is not available, or it has been agreed upon to apply the
film in some other manner, the various conventional and automatic methods of spray, dip, and
thickness shall conform to the above requirements.
4.3.1.4 Thickness. The dry film thickness of the test films shall be measured with the proper film
thickness gauge. When plates of small area are used, measurement of dry film thickness can be
made by weight of plates before and after coating and calculation from plate area and coating
solids.
4.4 Performance of test.
4.4.1 Film test. The film shall be tested at points not less than 0.375 inches from the edges. Tests
shall be made at regular drying intervals, such as 5 minutes, 15 minutes, or 1 hour, depending on
the speed of drying. The different stages of drying, defined herein, shall be determined as follows:
FED. TEST METHOD STD. 141D
2
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business