Evening capital. (Annapolis, Md.) 1884-1910, 1891-12-17
ANNAPOLIS MD, THURSDAY EVENING, DEcEMBER II, 1891
THE BIGGEST LATHE.
1T WILL TURN OUT HUGE GUNS
FOR UNCLE SAM.

ItIs I33 Fsst Long. and Is or Iron.
steel aud BronEe One Of Seven-Im-
nsnse Csstlngs-Now Nearing Conn
PietIon.
The largest. heaviest. anl most power
fu gun lathe in the world Is nov h-in;
built for the Naval Gun Shop, al " ash
insIon by William Sellers 4 Co.. of Pill.
aielphia. The contract for this stup...i-
dous instrument was awarded DecemheT
5, 1890, and the COMPANY las been work.
ing steadily upon il ever since, ana it
will soon be completed and setup to turn
out the most powerful cannon IN the
world
This lathe which is being constructed
Of bronze, steel, and cast iron, will weigh
SOC. 600 pounds aud will be 1873 feet in
length. It's greatest height will be Il
feet, its greatest " .ttii 10 feet six inches.
and its boring cal. NY ID inches. The
largest guns that the naval shops can
now construct are OF 1s inch bore, and
these are also the largest employed IN the
service When the new lathe is com.
pleted, however, the navy will ba
equipped with 16 inch bore shooting irons,
more than one e-third as big again as the
guns now in use.
AS soon as the lathe, which will cost
$4,000, Is completed, tile company will
begin operations upon seven others.
These will be only slightly smaller than
the former, and will be OF IA inch bore
They will be built at q cost, in round
numbers, Of $3.50 600, and viii be EN-.
ployed for boring and turning the gun
tubes and jackets
One OF the greatest features of the 10
inch lathe will be its face plate This
portion OF the lathe is now almost com
pleted; il is constructed throughout OF
cast steel, and weighs 180. 600 pounds 1t
is provided with four adjustable steel
jaws and a gear wheel, which has IS
teeth of iuch pitch and 10i inches face
Skilled workmen have been employed
day and night for three weeks in cutting
these teeth, and the operation is not yet
finished. Fourteen speeds, ranging from
O.4 revolution to 3 revolutions per min
ute, will be obtained, with cutt ng
pressure on a 80 inch diameter Of 140. 0U5
pounds on the slowest speed This plate
is said to be one of the most perfect AMI
costly steel structures that have ever been
built by machinists.
The bed OF the lathe is now lying in the
company's shops. and it, too is almost
finished This ID built of cast iron. and is
20 feet 10f inches long with width of 0
feet The wide part, OF main bed, has
four ways, two of which carry the tool
carriage on one side. while the other two
serve to hold the steady rests and tail
stock on the other. The middle ways are
formed in one section Of metal.
The boring arrangement is provided
with six inch steel screw, which is so
feet in length. This screw receives both
slow and quick motion from a short gear
shaft. connecting it with the proper train
of gears on the side of the boring bench
All the parts OF the lathe, which ipclud1
head stock, tool carriages. rests, tail
stock, boring arrangements, and counters,
ARE built on the same enormous scale, and
are perfect examples OF the machiuist's
art.
The IA inch lathes viii be constructed
upon the same model as the 16 inch i'm
strument, but will be slightly smaller
throughout. Each bed will be e5 feet in
length, and the other parts will be built
upon similar scale. They will be pushed
to completion as quickly as possible, but
the exact time this will require is uucer-
tain.