Alma record. (Alma, Mich.) 1878-1928, 1897-03-12
LEAD PENCIL MAKING
GRAPHITE, PIPE CLAY AND WOOD
THE COMPONENT PARTS.

An interesting Account OF How the Ma
teriais Are Reduced and Put Into Shape
Highly Perfected Machinery That Pro
duces In Large Quantities.
The "leads" of lead pencils are made OF
. mixture of German pipe clay and "black
lead, which Is not lead, but graphite. But
the first pencils were made of real lead,
and the name has chung to lead" pencils
ever since Graphite, or plumbago, Is near
ly pure form of carbon, and most of the
pencils made in this country use the
graphite mined at Ticonderoga, where
the only graphite mine of any consequence
in the United States Is located.
The graphite is taken in the lump from
the mines and carried to the reducing
mill, where it is ground or pulverized in
stamp mills under water. The fine par
ticles Of the graphite float away with the
water through number of tanks, collect
ing at the bottom of these reservoirs
1t is packed in barrels in the form Of
dust and sent to the factory, where tens Of
thousands of lead pencils are turned out
every day.
The pulverized graphite is so fine that
1t really is n dust, dingy in color and
smooth and oily TO the touch 1t is divided
into various grades of fincness by floating
1t on water from one tank to another.
The coarse dust sinks to the bottom OF
the first tank, the next finer to the bottom
of the second tank, and so on down the line.
the finest powder for the finest pencils set
thing in the last tank.
In another series of tanks the German
pipe clay, which is mixed with graphite
to secure the different grades of pencils,
from very soft to extra hard, is graded in
the same way by floating. The finest clay
is mixed with the finest graphite, and the
hardness of the pencil is secured by increas-
ing the proportion of clay in the mixture.
For the medium grades seven parts by
weight of clay are mixed with ten parts of
graphite The mixing is done under u
grinding mill similar to that used for
mixing paint, and water is added to facili-
tate the mix. The grinding stones are
about feet in diameter, and only the up
per one reyolycs.
After the graphite and clay are ground
together the mixture is put in canvas bags,
and the water is squeezed out under hy-
draulic press, leaving a mass the consist
ency of putty. This plaster material Is
placed in the forming press, which Is a
small iron cylinder in which solid plunger
or piston works up and down. A steel
plate having hole the size and shape OF
the lead is put under the open end of
the cylinder, and the plungcr pressing
down, forces the graphite through the hole,
making n continuous thread or wire of
graphite. As long as this thread is moist
1t Is pliable but it becomes brittle when
dry, so it is handled rapidly. 1t is cut into
three lead lengths, Strengthened out, and
then hardened in a crucible over "a coal
fire The leads when taken from the cruel.
BILE are ready for the wood.
Pine Is used for the cheap pencils, an
ordinary quality of red cedar is used for
the medium priced pencils, but nothing but
the best Florida Key cedar is put into the
best pencils.
The sawmills in Tampa, Fla, cut the
cedar into blocks about seven inches long,
and these are sawed into strips wide enough
for six pencils, but as pencils are made IN |
halves each strip is only thick enough for |
half pencil
When the strips are received at the fac |
tory, they are run through machine |
which cuts in each one six grooves, round |
or square, and ut the same time smooths |
the face of the wood Both strips are |
grooved alike, for, unlike the European |
made pencils, the American make has the |
lead equally in each strip.
The filling of the strips is done by girls. |
The first one takes a grooved strip of wood |
in her left hand and bunch of leads in |
the right. She spreads the leads out fan
shape, and with one motion fills the six |
grooves with leads.
Next TO her sits another girl who takes
the filled strip and quickly and neatly lays |
on 1T another grooyed strip which has just |
been coated with hot glue by a third girl |
The filled and glued strips are piled up |
ON each other and put in a press, where
they are left to dry The ends of the strips
Are evened off under a sandpaper wheel,
and then the strips are fed into machine
which cuts out the individual pencils,
shapes them and delivers them, smooth
and ready, for the color and polish In six
streams.
The coloring is done in liquid dyes, after
which the pencils are sent through the
machine. Then follows the
and finishing, all done by auto
matte machines, and finally the finished
,encils are packed around the oval, grooved
blocks, tied, papered and shipped out
The pencils are counted at various stages
If the making, and the counting is done
n way as simple as it is accurate. The
|
strips of wood are fastened the length of
he board and about four inches apart
In each strip are "A grooves. The work
nan grasps a handful of pencils and rubs
hem over the board once or twice, leaving
pencil in each groove.
In this way he counts gross Of pencils
n few seconds and does it without a
for only LA pencils can be placed
N the board at one time, and IL any
'rooves are empty the workman notices
be mistake at once. Chicago Record
|
The authorities on plastering declare
hat 100 yards of wall require /, 400 iaths
"a bushels of lime, four-fifths of a load OF
and, pounds of hair and pounds of
Iails
Twenty seven days from the date OF
,ost ipu lpttar IN Naxy Voxl, a. ..-;I1 |