Vernon County censor. [volume] (Viroqua, Wis.) 1865-1955, 1910-02-16

and during one Of these stages of this
process the chemicals which go to
make the final vulcanized product
tthe principal chemical of which is
sulphur) are mixed with the gum. Il
is these vulcanizing chemicals and
their proper proportions that institute
what really are genuine trade secrets
IN the work of tire making.
From the mixing machines the
sheets or long bands of rubber are
taken to the calendering machines,
composed chiefly of steam heated
rolls. A great part of the rubber
sticks to the rolls, but, strangely
enough, that part of which does come
out is a very thin, smooth and even
strip of material, though of course
very sticky. BY the adjustment of the
rolls these sheets can be made of any
desired thickness.
In order to handle these delie9te
and exceedingly sticky strips they
are reeled OF from the calendering
rolls between sheets of cotton cloth.
Thus they are easily handled and
carried about and ltevented from ac.
cumulating dirt When II is desired
It Is an easy matter TO unreel these
rolls OF cloth and to separate the gum
from the cotton.
The same rolls are used for max.
ing fabricated rubber; that is. kind
of canvas permeated with the ru,.
Der gum, and having one side com.
posed of me fabric and one side of
ru5oer. To produce this fabric ,lonp
strips of the canvas coated on on,
side with a cement are fed through
tae rolls in such a way that the rub.
Der gum, adhering to one is squeeze
down upon the canvas and caused tc
thoroughly permeate II. 1t is this fab
ricated rubber which is used in large
part in making up the outer case O,
shoes, OF automobile tires.
In the hand made process thes.
strips of fabricated canvas, in which
the canvas is cut on bias, are care
fuily laid by hand upon a cast iro
core, the purpose of the core being
TO give the correct shape TO the tire.
BY main strength the operator draws
the fabric around the core. using his
utmost endeavor TO put uniform
stretch throughout the material as IL
Is drawn around. Several LAYERS are
placed, one above the other. thus
building up the tire. During the MO.
cess OF building up the beading is put
IN around the rim, which always ex.
lists In an automobile tire to assist In
Fastening the outer casing to the rim
OF the wheel
Now here are machines that not
only make six 10 seven tires In the
same length of time required by hand
to make one, but they introduce into
the stretching end laying on of the
fabricated rubber with precision and
uniformity, so that one tire is almost
sure to last as long as any other.
After leaving the machines the core
is removed and, with its fabric and
rubber covering, is placed in a mould,
In which the application of pressure
to the two side squeezes the rubber
fabric tightly, the pressure required
being exerted by hydraulic rams.
While this pressure is being exerted
steam at about 275 degrees tempera.
tire is blown into the yulcanizing
vessel, and the action of the heat
causes chemical combination which
finishes the vulcanizing process.
The tire is now ready to receive
the outer coating of tread, which is
an extra thickness OF rubber put
around the running surface of the
tire. The tread is made separately
of built-up strips Of rubber gum, and
Is yulcanized by process similar to
that described above. 1t is Joined
to the fabric part OF the tire by means
of cement and bound TO the tire by
means of strips OF cloth. Meantime
the iron core has been removed and
its place taken in the tire casing by
what is known as an air bag, which in
reality Is an inner tube that will hole
air under pressure.
The next step is 10 take this band
aged tire TO another steam tank.
where the vulcanization is completed
and the tire and tread are mad,
practically into one piece The actios
of the heat, of course. expands Tn
air in the wind bag, and after all tho
stretch has been taken out OF the wei
bandaged cloth the expansion of the
air In the wind bag puts a very heav,
pressure on the rubber of the easing
and tends to knit the parts firmly to.
gether.
The inner tubes are simply mad.
and their production is at present al.
most entirely by hand work. TIE rub.
Der coming from the calender presses
Is cut into the proper width and the
edges. after being scarfed, are over.
tapped upon each other and cemented
N such way as to form one piece OF
material WIN placed tightly together.