Cork insulation; a complete illustrated textbook on cork insulation ...

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CORK INSULATION
CORK PAINT.*
For all surfaces, except ceiling and <strong>insulation</strong>, the surface of
the metal, in addition to the priming coats already applied, will be
given a thick coat of "under cork" or cork size (Formula No. 15).
The ground cork, which should be fairly large grained (large enough
to pass through a No. 8 sieve and be held on a No. 12), will then
be sifted and applied, and left until the paint is slightly set, when,
if required to efficiently cover the surface, a second coat of "under
cork" and ground cork will be applied in a similar manner to the
first coat in order to secure the adherence of the maximum amount
of cork. Over this will be applied two or more coats of white paint,
the first coat of which may be either applied by compressed-air spray
or by hand, the other coats to be applied by hand. The coating of
cork paint to be continuous and of substantial thickness. The above
method will be applied also to the outboard surface of metal plates
of ceiling and <strong>insulation</strong>, except that this plating will be laid flat to
receive the application of ground cork, and that the final average
thickness of cork paint is to be about ^-inch.
The inboard surface of all metal ceiling will be finished white
(not cork painted) glossed in officers' quarters. <strong>Cork</strong> painting should
be limited to the minimum absolutely required to prevent excessive
sweating, but where for instance, a part of the deck overhead would
require to be cork painted, the remainder of the deck, if of metal,
within the same compartment should be so painted in order to obtain
a uniform appearance. In a compartment generally finished in white,
glossed, where a portion of the surface is cork painted, the cork
paint will also be glossed.
AUTHOR'S NOTE: Formula No. 15.—"Under cork," for one gallon, consists
of: (a) Whiting, 10 pounds; (b) Hard Oil, J^-gallon ; and (c) Japan Drier, y^gallon.
One gallon of "under cork" will cover approximately 20 square yards, at
the weight of 2^ pounds per 100 square feet of surface. Ground cork, "Newport
Special," consists of natural cork bark ground to such size as to pass a screen
having 8 meshes per inch and be caught on a screen having 12 meshes per inch.
PULVERIZED CORK—SUBIRINE.t
It is said that considerable use is now being made of the newly
introduced French article to which the name of "subirine" has been
given. The substance consists of pulverized cork of different degrees
of fineness, known as impalpable, fine, medium and coarse, the pul-
verization being effected by very simple means, such as a horizontal
grindstone. Among these the medium powders have for some time
been employed in the French navy and by various navigation companies
for painting the sheet iron and partitions of the insides of
^^ 'Extracted from specifications of the United States Navy Department for
cork paint" to reduce sweating of metal surfaces.
tExtracted from Ice and Refrigeration, January, 1894.