The Redwood gazette. [volume] (Redwood Falls, Minn.) 1873-1940, 1878-11-28
The Process OF Making Rubber Shoes.

THE first operation, after receiving
the crude gum from the importer, is to
cleanse it. To facilitate this process,
the rubber, which comes in Jumps re-
sembling in size and shape soldiers
canteen, is cut into thin slices by means
of a large circular knife, revolving with
great speed land constantly wetted.
Then these slices are cut into small
pieces by means of o chopper ma
chine which resembles in its action a
common hay cutter-and afterward the
pieces are reduced to minute particles
in another machine, which, at the
same time, washes out all the dirt and
sand. Beside the accidental admixture
of foreign substances with the sap, the
natives are in the habit of throwing in
sand and ashes to increase the weight.
This grit, unless completely removed
from the gum, will show itself in the
shoe, impairing its smooth surface; and
hence much of the fine finish depends
upon the care taken at this stage.
The small particles of rubber, all
clean, are now shoveled into another
machine which rolls them together in
to rough sheets. These sheets are
then taken to the drying-room, where
they remain about three months to ad-
init of the complete evaporation of
the moisture. 1t is an important point
thoroughly to extract the moisture of
the gum, for if it is made up into shoes
before it is sufficiently dry, the watery
particles will expand under the heat Of
INFLAMMATION and cause blisters. After
the gum is sufficiently dry it is carried
into the grinding-room and fed into
machines called grinders, where, pass
ing between heavy iron rolls, heated
with steam, it is softened so as to per-
NIT of the admixture of the vulcaniz-
ing material. The call for low-priced
goods has led to extensive cheapening,
by which less expensive material than
rubber is added to lessen the cost.
Coal tar. lampblack and other cheap
and bulky articles are thus sometimes
used. The gum is then run into long
sheets between calenders. The sheets,
as delivered from the calenders, after
being cut into convenient lengths, are
carried to the cutting tables and cut in
to uppers and soles by means of pat
terms and sharp wet knives in the
hands of skilled workmen. The up
pers and soles are now ready to be
lasted. Meanwhile, in another depart
ment, the inings-whether of purple
stocking net for shoes, or of wooden
f1eecy cloth for " Arctics," or of heavy
felt for boots-are coated on one side
with rubber, by passing batch of gum
in company with the cloth between
heated steel rolls in another calender,
and, after being cut into various sizes,
many thicknesses at once, with dies in
drop press, are distributed to those
who make up the boots and shoes.
After af1ixing various strengthening
pieces of stifenings, etc. the
rubber upper is carefully laid on and
sticks fast to the rubber on the cloth,
with light pressure and smoothing
movement of the hand. No pegging
or sewing is required. The edges are
then trimmed, the sole is put on and
rolled down firmly, so as to adhere
closely in every part. The shoes are
now collected and carried to the var
nish room, where coat of elastic var
nish is quickly applied, and the shoe,
now of q greenish-brown color, is hung
in the heater. This varnish, beside i'm
parting the luster finish, protects the
rubber from being injured by the intense
heat of INFLAMMATION, and further pro-
tects the shoes when in use from the eff
fects of the atmosphere. 1t is found that
goods which are made up with dull fin
ish, and not having the protection of the
varnish, do not last so long as the var
nished goods.
The heater is a large, fire-proof room,
heated by means of large number of
steam-pipes. In the evening, when the
heater is full of goods, the doors are
closed, the steam turned on and the
baking begins. The heat is gradually
run up to nearly 800 deg, under the
supervision of experienced hands who
remain all night carefully watching
the progress Of the baking, as indi-
Gated by thermometers hung up inside
but visible through small windows in
the wall of the heater. Too much heat
renders the rubber brittle and rotten,
and not quite enough heat detains the
sulphur in the shoe, and causes its ap-
pearance afterward-when they be-
come what are called white'' goods.
These white or sulphurous goods are
really better to wear than those COM
pletely cured. During INFLAMMATION
the gum becomes very soft and runs
together into one homogeneous mass,
and finally, when a igher point is
reached, it hardens again. After remain
ingin the heater sufficient time-about
eightor ten hours in all-the shoes are
carried, at an early hour in the morn
ing, into the packing-room, where, aft
er being removed from the lasts, they
are laid in long glittering rows on the