Handbook on Japanning: 2nd Edition by William N. Brown
W >>
William N. Brown >> Handbook on Japanning: 2nd Edition
"In painting in oil-colour," says Mr. Dickson, "the craftsman trusts
largely to his badger-hair brush to produce his effects of softness
and marbly appearance; but in painting in water-colours, this
softness, depth, and marbly appearance are produced mostly by the
colour placed upon the surface, and left entirely untouched by badger
or any other brush. The colour drying quickly, does not allow much
time for working, and when dry it cannot be touched without spoiling
the whole of the work. The difference first of all between painting in
water and in oil colour, is that a peculiar grain exists with painting
in water that it is absolutely impossible to get in oil. The charm of
a marble is, I think, its translucency as much as its beautiful
colour; it is to that translucency (for in marble fixed we have no
transparency) that it owes its softness of effect, which makes marble
of such decorative value. This translucency can only be obtained by
thin glazes of colour, by which means each succeeding glaze only
partly covers the previous one, the character of the marble being thus
produced. This is done sometimes in oil-colour in a marvellous manner,
but even the best of oil-painting in marble cannot stand the
comparison of water-colour, and it is only by comparison that any
accurate judgment can be formed of any work. The production of marbles
in water-colour has a depth, softness, and stoniness that defies
oil-painting, and in some cases will defy detection unless by an
expert of marbles. It may be that first of all the materials employed
are more in keeping with the real material, as no oil enters into the
composition of real marble, and by using the medium of water we thus
start better, but the real secret is that by using water as a medium
the colours take an entirely different effect. In painting in
water-colour greys of any tint or strength can be obtained suitable
for the production of a marble of greyish ground, by pure white,
tinted as required, being applied of different thicknesses of colour,
all the modulations of tone being obtained by the difference in the
thickness of the colour applied."
VARNISHING JAPAN WORK.
Varnishing is the last and the finishing process in japanning. It
consists in (1) applying, and (2) polishing the outer coats of
varnish, which are equally necessary whether the plain japan ground be
painted on or not. This is best done in a general way with common
seed-lac varnish, except on those occasions where other methods have
been shown to be more expedient, and the same reasons, which decide as
to the propriety of using the different varnishes as regards the
colours of the ground, hold equally with those of the painting, for
where brightness is a material point and a tinge of yellow would
injure it, seed-lac must give way to the whiter resins; but where
hardness and tenacity are essential it must be adhered to, and where
both are necessary a mixed varnish must be used. This mixed varnish
should be made from the picked seed-lac as directed in the case of the
white japan grounds. The common seed-lac varnish may be made thus:
Take 1-1/2 lb. of seed-lac and wash it well in several waters, then
dry it and powder it coarsely and put it with a gallon of methylated
spirits into a Bohemian glass flask so that it be not more than
two-thirds full. Shake the mixture well together and place the flask
in a gentle heat till the seed-lac appears to be dissolved, the
shaking being in the meantime repeated as often as may be convenient;
then pour off all the clear and strain the remainder through a coarse
cloth. The varnish so prepared must be kept for use in a well-corked
glass vessel. The whiter seed-lac varnishes are used in the same
manner as the common, except as regards the substances used in
polishing, which, where a pure white or the greater clearness or
purity of other pigments is in question, should be itself white, while
the browner sorts of polishing dust, as being cheaper and doing their
business with greater dispatch, may be used in other cases. The pieces
of work to be varnished should be placed near the fire or in a warm
room and made perfectly dry, and then the varnish may be applied with
a flat camel-hair brush made for the purpose. This must be done very
rapidly, but with great care; the same place should not be passed
twice over in laying on one coat if it can possibly be avoided. The
best way of proceeding is to begin in the middle and pass the brush to
one end, then with another stroke from the middle pass it to the other
end, taking care that before each stroke the brush be well supplied
with varnish; when one coat is dry another must be laid over it in
like manner, and this must be continued five or six times. If on trial
there be not a sufficient thickness of varnish to bear the polish
without laying bare the painting or ground colour underneath more
varnish must be applied. When a sufficient number of coats of varnish
is so applied the work is fit to be polished, which must be done in
common work by rubbing it with a piece of cloth or felt dipped in
tripoli or finely ground pumice-stone. But towards the end of the
rubbing a little oil of any kind must be used with the powder, and
when the work appears sufficiently bright and glossy it should be
well rubbed with the oil alone to clean it from the powder and to give
it a still greater lustre. In the case of white grounds, instead of
the tripoli, fine putty or whiting should be used, but they should be
washed over to prevent the danger of damaging the work from any sand
or any other gritty matter that may happen to be mixed with them. It
greatly improves all kinds of japan work to harden the varnish by
means of heat, which, in every degree that can be applied short of
what would burn or calcine the matter, tends to give it a firm and
strong texture where metals form the body; therefore a very hot stove
may be used, and the stoving may be continued for a considerable time,
especially if the heat be gradually increased. But where wood or
papier-mache is in question, heat must be applied with great caution.
SECTION III.
JAPANNING OR ENAMELLING METALS.
In japanning metals, all good work of which should be stoved, they
have to be first thoroughly cleaned, and then the japan ground applied
with a badger or camel-hair brush or other means, very carefully and
evenly. Metals usually require from three to five coats, and between
each application must be dried in an oven heated from 250 deg. to 300 deg.
F.--about 270 deg. being the average. It has already been seen that the
best grounds for japanning are formed of shellac varnish, the
necessary pigments for colouring being added thereto, being mixed with
the shellac varnish after they have been ground into a high degree of
smoothness and fineness in spirits of turpentine. In japanning it is
best to have the oven at rather a lower temperature, increasing the
heat after the work has been placed in the oven. When a sufficient
number of coats have been laid on--which will usually be two only--the
work must be polished by means of a piece of cloth or felt dipped in
tripoli or finely powdered pumice-stone. For white grounds fine putty
powder or whiting must be employed, a final coat being afterwards
given, and the work stoved again. The last coat of all is one of
varnish. And here, as a preliminary remark, it is advisable that all
enamels and japans should be purchased ready-made, as any attempt to
make such is almost sure to end in disaster, while, owing to the fact
that such are only required for small jobs; it would involve too much
trouble and would not pay. It is for this reason that few japan
recipes are given, as, although many are available, they do not always
turn out as suitable for the purpose as could be desired, in addition
to which the ready-made articles can be purchased at a very reasonable
price and are much better prepared. The operator should procure his
enamels a shade or two lighter than he desires to see in the finished
article, allowing the chemical action due to the stoving to tone the
colours down. Another necessity is to keep the enamel thoroughly well
mixed by well stirring it every time it is used, as if this is not
done the actual colouring matter is apt to sink to the bottom, the
ultimate result being that streaky work is produced in consequence of
this indifferent mixing of the enamelling materials.
It is hardly necessary to state that all japanning or enamelling work
must be done in a room or shop absolutely free from dust or dirt, and
as far away as possible from any window or other opening leading to
the open air, for two reasons--one being that the draught therefrom
may cool the oven or stove, and the other that the air may convey
particles of dust into the enamelling shop. In fact, it cannot be too
much impressed upon the workmen that one of the primary secrets of
successful enamelling is absolute cleanliness; consequently all
precautions must be taken to ensure that the enamel is perfectly free
from grit and dust, and it must be so kept by frequent straining
through fine muslin, flannel, or similar material. The work having
been thoroughly cleaned and freed from all grease and other foreign
matter, it must be suspended or held immediately over the pan
elsewhere referred to, and the enamel poured on with an ordinary iron
ladle, or covered by means of the brush. When it has been permitted to
drain thoroughly, the work should be hung on the hooks on the rods in
the oven as seen in the explanatory sketch, care being observed that
no portion of the work is in such a position that any superfluous
enamel cannot easily drain off--in other words, the work must lie or
hang that it is always, as it were, on the slant. Always bear in mind
when shutting the oven door to do so gently, as if a slam is indulged
in all the gas jets will be blown out, and an explosion would probably
result.
Should the job in hand be a large one, it will be found as well to get
a cheaper enamel for the first coat, but if the work is only a small
job, it will not be necessary to have more than one enamel, of which a
couple of coats at least will be required. When the first coat has
thoroughly dried and hardened, the surface will have to be thoroughly
rubbed till it is perfectly smooth with tripoli powder and fine
pumice-stone, and afterwards hand-polished with rotten-stone and putty
powder. And here it may be remarked that the finer the surface is got
up with emery powder and other polishing agents the better will be the
enamelling and ultimate finish. The rubbing down being finished,
another coat of enamel must be applied and the work baked as before,
care being always taken to keep the enamel in a sufficiently fluid
condition as to enable it to flow and run off the work freely. It can
easily be thinned with a little paraffin. A third coat will frequently
be advisable, as it improves the finish.
In enamelling cycles, it is well to hang the front forks crown
uppermost when they are undergoing the final baking, and it is
advisable to bear in mind that wheels require an enamel that will
stove at a lower temperature than is called for for other parts of the
machine. Some japanners advocate the fluid being put on with camel-or
badger-hair brushes, and for the best descriptions of work, final
coats, and such like, I agree with them; but this is a detail which
can be left to the operator's own fancy, the class of work, etc.; but
I would remind him that applying enamel with a brush requires much
care and a certain amount of "knack". It is something like successful
lacquering in brasswork--it looks very simple, but is not. Each
succeeding coat of japan gives a more uniform and glossy surface, and
for this reason it may, in some cases, be necessary to repeat the
operation no fewer than half a dozen times, the final coat being
generally a layer of clear varnish only, to add to the lustre.
Care must be taken for light-coloured japans or enamels not to have
the temperature sufficiently high to scorch, or the surface will be
discoloured, as they require a lower temperature for fixing than the
dark japans, which, provided the article is not likely to be injured
by the heat, are usually dried at a somewhat high temperature. The
preceding instructions apply only to the best descriptions of work.
When pouring enamel by means of the ladle over pieces of work, do not
agitate the liquid too much--at the same time taking care to keep it
well mixed--so as to form air bubbles, as this will cause trouble, and
in pouring over the work do it with an easy and gentle and not too
hurried a motion. In japanning curved pieces, such as mud-guards,
etc., in hanging up the work in the oven see that the liquid does not
run to extremities and there form ugly blots or blotches of enamel.
When white or other light tones are used for japanning they are mixed
with japanners' varnish, and these require more careful heating in the
oven or stove than darker tints or brown or black.
[Illustration: FIG. 1.--Trough for Dipping Bedstead Frames and other
Large Work.]
ENAMELLING BEDSTEAD FRAMES AND SIMILAR LARGE PIECES.
At Fig. 1 is shown a trough in which large pieces, such as bedsteads,
bicycle frames, etc., are dipped or immersed. For the first-mentioned
class of work such high finish is not required as for bicycles, and
consequently the enamel need not be applied with a brush, nor will it
be necessary to rub down the work between each coat, but instead the
pieces can be literally dipped in the tank of liquid, then allowed to
drain on to the dripping-board--the superfluous enamel thus finding
its way back into the trough or tank, the dripped articles being
afterwards placed in the oven to harden. The trough must be of
sufficient dimensions to allow the pieces of work to be completely
immersed, and the dripping-board should be set at an angle of about
45 deg..
Bedstead frames will never require more than two coats and the
commoner class of goods only one. I would not advise the tradesman in
a small way of business to go to the expense of a trough, etc., as it
calls for much more room than is ordinarily available, but if he has
the necessary plant for bicycle work he can, of course, do an
occasional job of the other kind.
JAPANNING TIN, SUCH AS TEA-TRAYS AND SIMILAR GOODS.
For japanning sheet-iron articles, which are really tin goods, such as
tea-trays and similar things, first scour them well with a piece of
sandstone, which will effectually remove all the scales and make the
surface quite smooth. Then give the metal a coating of vegetable
black, which must be mixed with super black japan varnish, thinned
with turps, and well strained. Only a small quantity of this varnish
is necessary, as it will dry dead. The article must then be placed in
the stove to harden at a temperature of 212 deg. F., there to remain for
from ten to twelve hours. When taken out of the stove, the articles
must be allowed to get cold, after which they must be given a coat of
super black japan, which, if necessary, must be thinned with turps, a
stiff, short bristle brush being employed, and the varnish put on
sparingly, so that it will not "run" when it gets warm. Two coats of
this varnish on top of the vegetable black coating are usually
sufficient, when done properly, but a third coating much improves the
work, and from ten to twelve hours' hardening will be necessary
between each coating. The small lumps which will be more or less
certain to arise will require to be rubbed down between each
application by a small and smooth piece of pumice-stone.
If it is desired to add gold or bronze bands or any kind of floral or
other kind of fancy decorations, these are painted on, after the
ground japanning has been done, in japanners' gold size, and then the
gold leaf is applied, or the bronze or other metal powder is dusted
on, after which the objects so treated are again placed in the stove,
where they will not require to be kept near so long as for ordinary
japanning. After they have been removed, the gilt or bronzed portions
must be treated with a protecting coat of white spirit varnish.
Transfers can be applied in the same way.
Tinned iron goods are the most largely japanned, and for these brown
and black colours are principally employed. Both are obtained by the
use of brown japan, the metal having a preliminary coating of black
paint when black is required. Only one coating of brown japan is given
to cheap goods, but for better articles two or more are applied. For
these it is possible that a final dressing with pumice-stone, then
with rotten-stone, and rubbed with a piece of felt or cloth, or even
the palm of the hand, may be necessary, but as a rule not.
Large numbers of articles of the above description, such as tea-trays,
tea-canisters, cash-boxes, coal-boxes, and similar goods, are japanned
at Birmingham, and it is to such that the preceding instructions
apply.
ENAMELLING OLD WORK.
In all cases of re-enamelling old work, it is absolutely necessary to
remove all traces of the first enamelling, and if this has been well
done in the first instance, it will prove no mean job. The best way to
clean the work is to soak it in a strong "lye" of hot potash, when the
softened enamel can be wiped or brushed off--this latter method being
pursued in the more intricate and ungetatable portions of the work.
New work, which has not been enamelled, can be treated in the same way
for the removal of all grease, stains, finger-marks, etc., and too
much attention cannot be paid to the initial preparation of the
surface of the metal, to have it thoroughly even and smooth, as it
adds so much to the ultimate finish and appearance of the work. Plenty
of labour must be bestowed before the final coat, as any blemish will
show through this finishing, and so mar what would otherwise be a
highly satisfactory bit of work. In all kinds of bicycle work, whether
new or old, the most satisfactory results are obtained by the
application of at least two, and sometimes four or five, successive
coats of good but thin enamel, as this will impart the necessary
perfect coat, combined with durability, a high finish, and a good
colour. A good enamel should be sufficiently hard, so as not to be
scratched on the merest touch or rubbing. It will, of course, be
understood that no solder-work must be put into the stove, or the
pieces will separate. Should any of this work be discovered, the
pieces must be taken apart, and then brazed together before being
enamelled, and put in the stove.
SECTION IV.
THE ENAMELLING AND JAPANNING STOVE--PIGMENTS SUITABLE FOR JAPANNING
WITH NATURAL LACQUER--MODERN METHODS OF JAPANNING WITH NATURAL
JAPANESE LACQUER.
APPLIANCES AND APPARATUS USED IN JAPANNING AND ENAMELLING.
Besides the various enamels or japans and varnishes of various
colourings and the stove, which will be found described and
illustrated, together with the trough, in other pages, the worker will
need some iron pots or cauldrons in which to boil the potash "lye" for
the cleansing, more particularly, of old work, some iron ladles both
for this work and for pouring the japan on the articles to be covered
therewith, a few badger tools and brushes for small fine work, some
hooks for the stove, a pair of pliers, a few bits of broom handle cut
into short lengths and made taper, so as to fit into the tubes, etc.,
of bicycles and other work, so as to keep the hands as free from the
japan as possible, some emery powder, pumice-stone powder, tripoli,
putty powder, whiting, and a piece of felt or cloth. If he is also
doing any common work, a stumpy brush of bristles and a soft leather
will also be requisite, together with a file or two. These will about
comprise the whole of the articles required, not very expensive, all
of which will really not be required by a beginner.
Owing largely to the strides made in the cycle trade enamelling is
stoved by means of gas, and of this a plentiful supply is necessary.
Enamelling stoves may really be described as hot-air cupboards or
ovens, and for a stove which will answer most requirements--say one of
6 feet by 6 feet by 3-1/2 feet--six rows of atmospheric burners will
be necessary to heat it, while it will be also advisable to fix pipes
of 1-1/4 inch internal diameter from the gas meter to the stove. The
atmospheric burners can be made from the requisite number of pieces of
1-1/4-inch gas tube 3-1/2 feet in length, one end of each being
stopped, and having 1/3-inch holes drilled therein at intervals of
about 1 inch, the other end being left open for the insertion of
ordinary 3/8-inch brass gas taps. Another plan preferred by some
japanners is to have three rows of burners the full length of the
stove, which, under some circumstances, due to structural conditions,
will be found more suitable. Anyway, whatever the position of the
stove, allowance must be made for a temperature up to 400 deg. F. to be
raised. In old-fashioned ovens the heat is applied by means of
external flues, in which hot air or steam is circulated, but this
system is generally unsatisfactory, the supply of heat having to be
controlled by dampers or stop-cocks, and this has given place to the
gas apparatus. Another simple form of oven, though not one which I
shall recommend, is a species of sheet-iron box, which is encased by
another and larger box of the same shape, so placed that from 2 to 3
inches of interspace exists between the two boxes. To this interspace
heat is applied, and a flue will have to be affixed to this apparatus
to carry off the vapours which arise from the enamel or japan. For
amateur or intermittent jobbing work the oven illustrated in Figs. 2
and 3 is about as good as any, though to guard against fire it would
be as well to have a course of brickwork beneath the oven, while if
this is not possible on account of want of height, a sheet or so of
zinc or iron will help to mitigate the danger. It is also advisable,
if the apartment is a low-pitched one, to have a sheet of iron or zinc
suspended by four corner chains from the ceiling in order to protect
this from firing through the heat from the enamelling oven. Of course,
it will be understood that every portion of the stove must be put
together with rivets, no soldered work being permissible.
[Illustration: FIG. 2.--Door of Oven when Shut.]
To those who wish to construct their own stove, it will be found that
the framework can be shaped out of 1-inch angle iron, the panels or
walls being constructed of sheet-iron of about 18 gauge, the whole
being riveted together. The front will be occupied in its entire space
by a door, which will require to be hung on strong iron hinges, and
the framework of this door should be constructed of 1 inch by 1/4 inch
iron--a rather stouter material will really be no disadvantage--to
which the sheet-iron plates must be riveted. In the centre of the door
must be cut a slit, say 1-1/2 inches by 9 inches, which will require
to be covered with mica or talc behind which must be placed the
thermometer, so as it can be seen during the process of stoving,
without the necessity of opening the door, which, of course, more or
less cools the oven. And, by the way, this thermometer must register
higher than the highest temperature the oven is capable of reaching.
Above is shown a sketch of the stove, interior and exterior, which
will give an idea of what a japanner's stove is like.
[Illustration: FIG. 3--Showing Stove when Open, and Back of Door.]
Inside the stove it will be necessary to fix rows of iron rods, some
four inches from the top, from which to suspend the work, or
angle-iron ledges can be used on which the rods or bars can be fixed,
these arrangements being varied according to the particular
description of work, individual fancy, or other circumstances. Large S
hooks are about the handiest to use. A necessary adjunct of the stove
is a pan, which can be made by any handy man or tinworker, which
should be made to fit the bottom of the stove above the gas jets, it
being arranged that it rests on two side ledges, or along some rods.
One a couple of inches in depth will be found sufficient, and it will
repay its cost in the saving of enamel, it being possible with its use
to enamel a bicycle with as little as a gallon of enamel. Some workmen
have the tray made with a couple of hinged side flaps, to turn over
and cover up the pan when not in use, but this is a matter of fancy.
Of course, they must always be covered up when not in use. For those
who would prefer to use Bunsen burners, I show at Fig. 4 a sketch of
the best to employ, these having three rows of holes in each.
[Illustration: FIG. 4.--Bunsen Burner.]
When brick ovens are employed they must be lined with sheet-iron, and
in these very rare circumstances where gas is not available, the stove
can be heated with coal or wood, which will, of course, involve a
total alteration in the structural arrangements. I have not given the
details here, as I do not think the necessity will ever arise for
their use, and for the same reason I have refrained from giving the
particulars for heating by steam and electricity, or the other methods
which have been adopted by various workers, as there is no question
but that a gas stove or oven, as described, is about the best and
handiest for jobbers or amateurs.