tted 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
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