Charlevoix county herald. (East Jordan, Mich.) 189?-1953, 1905-07-15
MANUFACTURE OF coRKs.


|
outer bark of an evergreen oak tree
which grows In Spain, Portugal, AL
geria. Morocco and to some extent in
Italy. Its peculiar properties, espe
cially its lightness and its compressi'
bility. make 1t valuable for scores OF
purposes, but its original use. In the
manufacture Of corks, or shoppers fol
bottles, still consumes the greater part
Of all that is brought to market.
The cork oak varies in diameter from
six inches to three feet. BY gener.
GUS provision of nature the tree may
be periodically stripped of its outer
bark without losing its life.
Twenty years is the usual age at
which the first cutting is made. After
that the cork may be harvested about
every ten years. The first cut, which
Is called virgin bark, is of little value,
as 1t is coarse in texture and deeply
scanned. The tree may be expected to
live and yield cork until it is $50 years
old.
In Spain and some other European
countries corks are still made by hand,
each one being pared from a square
block by common knife. In this
country, where are made the finest
corks in the world, the work is done
by machinery, all of which is of
American invention and manufacture.
Every boy who has ever whitfield a
cork for a fishing dob or a popgun
pellet knows how difficult the material
is to cut smoothly. To do it well his
knife must be as sharp as razor and
must be used with a drawing motion.
not mere pressure, and if the cork is
wet, so much the better. The same
difficulties confront the manufacturer
by machinery, and are met in the same
way
The bark, after having been wet, and
then allowed to remain for time in
damp cellars to soften, goes first to the
stripping machines, which reduce it to
slabs of size proportionate to the
corks to be made. These machines are
merely small iron tables, through which
appear very thin steel disks, like circu-
lar saws, except that they have no
teeth. They are really keen edged
steel knives, as thin as paper. and
running at high rate of speed, but so
smoothly that they seem to the specta-
tor to be standing still.
The little slabs or strips of cork so
next to the 'blockers." The cutters
here are cylindrical steel punches, or
tubes, with razor edges. They are ar
ranged in rows or gangs" and in
stead of being simply pressed through
the cork, are also revolving at high
speed, and so cut their way through.
Having perforated the slab the cutters
back away automatically, while plung
ers like pistons working in the cylin-
ders come forward and punch out the
cores, which, for some purposes, are
already finished corks.
They are, Of course, perfectly cylln-
drical, that is, without taper, and in
that form they are preferred by bot
tiers of effervescent liquids because
their shape enables them the better to
resist the pressure of the restrained
gases.
But for the use Of druggists, who are
the great users of corks and need the
WY hhCSt, tdpClihS otoppCl 10 PlS
ferred, and this necessitates another
operation. The tapering machines arc
:un mostly by young women. Each
machine consists of little lathe which
centres the cylindrical cork automati
cally and then brings it into contact
with the edge Of the cutting knife,
which, like the cutter Of the slicing
| oh ic Thin cfaa1 Iicl-
the cork touches this knife thin shay
ing rises and curls away, light as
puff Of smoke.
One who knows nothing Of the ma
chinery could see no reason for it, but
during the second that the cork has
been in contact with the apparently
motionless disk some dozen yards of
work, and the cork is now a perfect
truncated cone, with a fine, satin-like
surface and an even and regular taper.
BY hand very rapid and skilful cutter
can turn out twelve or fourteen gross
IN day. With these machines one
girl will produce 400 gross.
There are few businesses in which
| lHc VI WASTE luattIldl 10 SO
large as in the manufacture of corks.
In the best managed factories it ranges
from sixty to seventy per cent, but
American ingenuity and industrial de-
velopment have succeeded in trans
forming it into source Of profit. BY
grinding the waste to various degrees
Of fineness and pressing it. with glue
or shellac, into various shapes. it is
made useful for the inner soles of
shoes, for bathroom mats. for insula-
ton in refrigerator plants and the
| deadening of sound in apartment
houses, the making of bicycle handles
and the grips Of tennis rackets, fly rods
and golf clubs, and there are dozens of
other uses for the waste which are
quite as interesting.
A few years ago one manufacturer
Of corks was paying a teamster dol
lar a load to cart away his waste and
dump it on a refuse heap. To-day he
receives $50 ton for the very cheap
est quality of this waste. - Edward