St. Tammany farmer. [volume] (Covington, La.) 1874-current, 1904-08-27
ODDITIES OF MACHINERY.

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Some of the wonders of machinery,
such as the erratic operation of certain
engines at particular times, are little
understood, even by practical machin-
lists, says Journal of the trade.
Everyday things which are perfect
" familiar to mechanics of one class
are totally unintelligibIe to the work
man in another branch.z+.Men who haze
worked lifetime in fashioning cast
iron under the lathe are greatly sur
prised on learning that the same ma
terial, when employed in the heating
pipes of blast furnace stove, grows
from six inches to foot in length from
constant use. And the furnace man is
equally unprepared to hear that the core
bars used for casting pipes lose as much
as three inches in casting 20 or 80
pieces. 90
In practice, for instance, a piston rod
lacking of easy fitting babbit bushing
is used. When these bushes become
sufficiently worn to leak, we close
them up by COMPRISING them in the wa
ter cylinder of hydraulic press. In
this operation a mandrel somewhat
smaller than the piston rod is put inside,
and with all the pressure we can bring
t. bear we have never been able to
compress the bush SO as to grasp the
mandrel tight, and yet occasionally we
have had these bushes shut down while
the engine was running so as to grasp
the piston rod as if gripped in a wise,
to break the bushes asunder, indeed, or
to make this necessary in order to get
th EN- of.
Again, in the foundation of embossed
work, two dies are used, the female die
often being made by driving the hard
ened male die into a block. of soft STEEL
This operation is easily performed by
a few blows of the drop hammer. 1t
drives in and raises the soft metal with
out distorting the block in any other
particular. Had the same operation
been attempted by means of the hy
draulic press the block would probably
be upset one-fourth it's depth, the sides
bullying out or the piece crushed, with
out producing other than a faint mark
ing of the outline of the male die.
When the lawn mower was first in
troduced, the inventor was considered
little short of mechanical hereto to
imagine that he could get sufficient
traction with two light wheels to ro-s
tate cylinder six times their own
weight at six times their velocity, and
cut the grass in addition. The worm
that drives the bed of Sellers planer
does not wear out half as fast. as it
should, and there is possibly something
unexpected about it, even to the makers
themselves ks3s
ALI by 1s-inch cylinder engine, which
had been running year at 1856 revolu-
lions minute on an unusually solid
began one day without ap
parent cause to shake endwise, and be-
fore night had shaken itself loose. AS
no harm resulted, and the work was
pressing, the repairing of the foundation
was postponed until vacation time,
about month. distant Before that
time arrived, however, the shaking
ceased, and the engine ran perfectly
smooth in spite of the impaired founda-
ton
Another and even more curious in
stance OF the unexpected was that of
well-known electrician who built and
tested for three years q certain piece of
which promised to be ex-
tensively used AS it worked perfect
ly, a large amount of capital was put
into buildings and plant for the produce
ton OF these pieces of apparatus Z. for
the market, and many were built; but
the manufacturers were totally unable
to reproduce the original either in eff
feet or durability. as 4
In another case two similar boilers
were connected by neeks at top and |
bottom, and fire built under each OF
them, the boilers being about half full. |
The water. without apparent cause, be-
laved very strangely. all going into |
one boiler, and then into the other.
When the play was at its height, the |
BOSS, considering the lives of the men |
and the premises of more value than |
he cause of science ordered the fires
1rawn, and the cause could never be
determined. ..s-,.. .y~.s.se4sy