Clinch Valley news. [volume] (Jeffersonville, Va.) 18??-2019, 1889-02-01
HOW BELLS ARE MADE.
OPERATIONS REQUIRING GREAT
CARE AND SKILL.
The Musical Tono- Forming the
Misunderstanding and Polishing
the Bell-Testtne the Tone


Misunderstanding and Polishing
tho BelI-Testing tho Tone.
II may not be generally known, says q
writer in Stores and Hardnare, that there
are only five concerns in the United
states engaged in the mauufacture of
church, school, and CHI me bells.
Contrary to the popular idea, the ex-
act musical tone Of bell depends neither
upon tho metal nor upon any change in
1t attor being cast. Ii tho bell should
not be of the exact pitch, there is no
alternative but to melt it over and re-
cast it until the proper tone is secured.
Hence, il is clear that the greatest care
must be exercised, and the most thor
ough skill displayed.
The first operation, and the one upon
which success depends, is the forming
OF the mouths They arc made accord.
Ing to plans which arc rIst prepared to
demonstrate the weight, thickness, and
dimensions necessary to produce the re-
quired tone. The moulding is done en-
tirely by hand without the use of pat.
terms. For the inside, the shape is made
up OF loan, which is merely sand mixed
with enough clay to make it cohesive.
with nothiag but trowcl, n paddle,
and n s hands, tho operator mouids the
lonm into the desired shape, work
ing from the bottom toward the apex.
The work is necessarily slow, us great
care must he exercised as any variation
from the plans would inevitably ruin tho
ellie t, and frequent mcasui ements arc
taken to see that there are no dcviations
The surface IS now covered with black
lead. This is mixed into n thick paint,
or mortar. and applied with n hrush.
Each coat must be allowed TO dry, and
successive coats applied until it rca"hes
thickness oil about three quarters of an
inch, OF until the desired sh'pe is &c.
curatoly secured. The outside half of
the mould is built up of loan in the
same way, only in this case no coating of
plnmbago is used. The exterior mould
fits over the inside mould, the spncc be-
tween the two determining the thickness
OF the Lcll. The moulds being finished,
they are placed in position in pit in
front of the furnace. At the apex, or
at the point where the bell would be
hung, nm opening is made in the outside
mould of about two inches in diameter.
A trough thea carries the molten metal
directly into the mould
The furnace is very similar to those
generally used in melting large guam
titles of brass. The melting pot is built
between two irc.boXcs, SO constructed
that the heat strikes the sides and bot
tom with almost equal force. Getting
quick results. The metal used is simply
ingot copper and tin, in the proportion
of four pnr,s of the former to ono CT the
latter. The copper is first melted, and
then the tin is put into the molten mass,
soon becoming part of it. The kettle
has n capacity of about ton. For n
bell weighing three hundred pounds, the
mould is completely filed in seven or
eight minutes. or bells weighing six
hundred pounds, it requires about fifteen
minutes, and so on.
The bell having cooled sufficiently,
the moulds are broken, and it is taken
out and turned over to the polishcr. The
inside, having been moulded against the
smooth surface of black lead, needs no
polishing, but the outside requires at
tention in that respect. The operation
is very simple. The bell is hoisted to
the center of double revolving table.
The part the bell rests upon revolves
one way, the surrounding part in an
opposite direction. This latter part is
so constructed that it will hold n large
quantity of coke. Thus, in revolving,
the coke scours the outside of the bell,
the result being Il smooth, bright sur
face.
Refore polishing, however. the tone of
the bell is tested, and it is again tested
after polishing, as carefully as the string
of piano or the reed of an organ. ii
satisfactory, nothing remains to do but
the mounting.
An idea Of the great accuracy that
must be displayed in the plans and prep.
aration of the moulds can be seen in that
from ten to twenty-five pounds of metal,
either too much or too little, in bells
weighing from 100 to 1000 pounds, or a
variation OF from one twentieth to one
twelfth If an inch in thickness, will affect
the tone. The successful manufacture
of chimes and peals, therefore. can only
he done by those whose knowledge of
the business Is rs accurate rs instinct.
and this is possessed only by those who
have followed the business for lifetime.