Paint Technology and TestsGardner, Henry A. (Henry Alfred)
Science
Paint Technology and Tests
Gardner, Henry A. (Henry Alfred)
Paint
=Inspection of Atlantic City Tests.= During the month of March, just one
year after the placing of the painted panels on the Atlantic City fence,
an inspection was made jointly by a committee representing the Master
Painters' Association of Pennsylvania, the Scientific Section of the
Paint Manufacturers' Association of the United States, and certain
members of sub-Committee E of the American Society for Testing
Materials.
=Methods Used at Inspection.= One of the most important tests made when
inspecting paint is the determination of the chalking taking place.[19]
There was developed during the inspection of the Atlantic City panels a
new method for determining the comparative chalking of the various
paints. It was thought desirable to secure a method, if possible, that
would show results which might be photographed and even tabulated in
percentage form, if desired. The apparatus for the new test consisted of
a small strip of black felt three inches wide by five inches long,
placed across a small block of wood which would fit in the palm of the
inspector's hand. This outfit resembled a blackboard eraser and was used
in a similar way. By holding the apparatus firmly against the panel and
drawing it half-way across the panel in a straight line toward the
operator, there was obtained on the black cloth a white mark
proportional in intensity to the amount of chalking which had taken
place on the given area. When a series of these cloths were made, they
were assembled and photographed for comparison. It should be noted that
the above chalking test is useful only where the painted panels under
examination have been exposed over a period of one to two years, during
which period the chalking of paints has been shown to be greatest and
the chalked surface of a fairly adherent nature. Where longer exposures
have been made and where rains have removed from the painted panels a
considerable amount of the chalked pigment which has formed, such a test
would not be fairly representative of the amount of chalking which had
taken place.
[19] Mr. Macgregor of the Picher Lead Co. has just developed a new
test to determine the relative imperviousness of paints which
have begun to chalk. He draws a mark about two inches long upon
the painted surface with a fountain pen. The ink mark will spread
rapidly to a wide area if the chalking is of a bad order. If the
chalking is slight and the film in good condition, the ink mark
will not spread.
[Illustration: Series of Black Felt Cloths used in making the Chalk
Tests on the Various Formulas. Numbers over Cloths represent Panels]
[Illustration: CHALKING.--Type of Decay Exhibited by Improperly Made
Paint (magnified view)]
[Illustration: CHECKING.--Type of Decay Exhibited by Improperly Made
Paint (magnified view)]
[Illustration: BLISTERING.--Type of Decay Exhibited by Improperly Made
Paint (magnified view)]
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Elsewhere in the archive
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account