This avoids the danger of melting one before the other reaches the
brazing point.
The heat should be continued only long enough to cause the spelter to flow
into place and no longer. Prolonged heating of any metal can do nothing but
oxidize and weaken it, and this practice should be avoided as much as
possible. If the spelter melts into small globules in place of flowing, it
may be caused to spread and run into the joint by lightly tapping the work.
More dry flux may be added with the spatula if the tapping does not produce
the desired result.
Excessive use of flux, especially toward the end of the work, will result
in a very hard surface on all the work, a surface which will be extremely
difficult to finish properly. This trouble will be present to a certain
extent anyway, but it may be lessened by a vigorous scraping with a wire
brush just as soon as the work is removed from the fire. If allowed to cool
before cleaning, the final appearance will not be as good as with the
surplus metal and scale removed immediately upon completing the job.
After the work has been cleaned with the brush it may be allowed to cool
and finished to the desired shape, size and surface by filing and
polishing. When filed, a very thin line of brass should appear where the
crack was at the beginning of the work. If it is desired to avoid a square
shoulder and fill in an angle joint to make it rounding, the filling is
best accomplished by winding a coil of very thin brass wire around the part
of the work that projects and then causing this to flow itself or else
allow the spelter to fill the spaces between the layers of wire.
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