The Washington times., 1917-04-07
MAKING OF MOTOR
CARS INTERESTING
Various Parts of the Modern
Automobile Made With
Astonishing Speed.

There is no manufacturing plant
more interesting than a motor car
factory. In fact, it is little short of
marvellous to watch the speed with
which the various parts which go to-
ward making up a spick and span
1917 automobile are manufactured.
While in Detroit recently, a repre-
sentative. of this paper visited the
great factories and inspected every
process OF manufacture. from the
foundry to the assembling depart
ment Among the most interesting
operations were the processes neces-
sary to make a single part, the cam
shaft used in the new Studebaker
cars. This part is a difficult one to
manufacture, yet many OF the opera
tions in its making are the same as
those required to manufacture the
axle shaft, transmission shaft, pro-
peller and many Of the other 1000
parts.
The steel for the cam shaft comes
to the factory in bars. This bar is
cut off by gigantic shears into bill
lets about a foot long. The billet is
heated to a malleable state, just as the
blacksmith of old heated the piece of
steel to make a horseshoe, but the
cam shaft, instead of being ham
mered into shape on an anvil, is
placed on the die of a great steam
hammer
shaped Roughly Into Form.
The die is the shape of the cam
shaft-the hammer which strikes the
steel is guided to strike exactly the
same spot on the die each time. The
face of the hammer is also cut in the
shape of the cam shaft. This great
hammer is operated by steam, strik-
ing 1t a smashing blow. In a few
strokes the billet of steel is elongated
and shaped roughly into its final form.
At the same time the blows of the
drop-forge hammer press the grain OF
the steel together and refine it. After
this operation the shaft is allowed to
cool in the air. 1t is then heated
again slowly to 100 degrees
Fahrenheit in a furnace. where the
heat is electrically. measured. This
heat treatment readjusts the grain of
the steel after the strains of the drop
forge hammer.
1t then goes through several lathes
which still further shape it to itsfinal
IL
to length and centered so that 1t can
be turned accurately, and the grind
ing machines must be especially made
TO machine the cam surface into a
parabolic shape-that is, curved
something like an egg. After these
roughing processes the shaft is again
trued, inspected and, IL 1t passes
muster, packed in a heat treating
furnace, where II is kept for eleven
hours under a temperature of 1,700
degrees Fahrenheit.
Surface @DIamond Hard /
Under this heat a chemical sub
stance slowly permeates the surface,
grain of the steel, and when
the steel is fixed by the next
heat treatment, makes its surface
diamond hard after that treatment
So skillfuIly has the steel expert de-
veloped this process that extreme
hardness has been procured without
the shaft being made brittle. But,
bear in mind, the hardness extends
only Just below the surface of the
steel The core of the shaft is still
as tough as the horseshoe nil
As a last finishing process 1t is
cleaned Strengthened, inspected and
then passed on to the final grinders.
Here it is ground to shape under
emery wheels. Automatically. the
emery wheels are guided over the
curved surface of the cams SO as to
insure accuracy to the one-thousandth
Of an inch On six-cylinder cars there