tly white japan ground and of the first
degree of hardness has always been difficult to attain in the art of
japanning, as there are few or no substances that can be so dissolved
as to form a very hard varnish coat without being so darkened in the
process as to quite degrade or spoil the whiteness of the colour. The
following process, however, is said to give a composition which yields
a very near approach to a perfect white ground: Take flake white or
white lead washed and ground up with the sixth of its weight of starch
and then dried, temper it properly for spreading with mastic varnish
made thus: Take 5 oz. of mastic in powder and put it into a proper
vessel with 1 lb. of spirits of turpentine; let them boil at a gentle
heat till the mastic be dissolved, and, if there appear to be any
turbidity, strain off the solution through flannel. Apply this
intimate and homogeneous mixture on the body to be japanned, the
surface of which has been suitably prepared either with or without the
priming, then varnish it over with five or six coats of the following
varnish: Provide any quantity of the best seed-lac and pick out of it
all the clearest and whitest grains, take of this seed-lac 1/2 lb. and
of gum anime 3/4 lb., pulverize the mixture to a coarse powder and
dissolve in a gallon of methylated spirits and strain off the clear
varnish. The seed-lac will give a slight tint to this varnish, but it
cannot be omitted where the japanned surface must be hard, though
where a softer surface will serve the purpose the proportion of
seed-lac may be diminished and a little turpentine oleo-resin added to
the gum anime to take off the brittleness. A very good varnish
entirely free from brittleness may, it is said, be formed by
dissolving gum anime in old nut or poppy oil, which must be made to
boil gently when the gum is put into it. After being diluted with
turps the white ground may be applied in this varnish, and then a coat
or two of the varnish itself may be applied over it. These coats,
however, take a long time to dry, and, owing to its softer nature,
this japanned surface is more readily injured than that yielded by the
shellac varnish.
According to Mr. Dickson, "the old way of making a cream enamel for
stoving (a white was supposed to be impossible) was to mix ordinary
tub white lead with the polishing copal varnish and to add a modicum
of blue to neutralize the yellow tinge, stove same in about 170 deg.F. and
then polish as
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