IMPROVED MACHINERY
Year: 1854

page_text: LETTERS PATENT to Samuel Colt, 'of Spring Gardens, in the County of
Middlesex, Gentleman, for the Invention of IMPROVED MACHINERY FOR
PROVISIONAL SPECIFICATION left by the said Samuel Colt at the
Office of the Commissioners of Patents, with his Petition, on the 12th
April 1854.
·I, SAMUEL COLT, of Spring Gardens, in the County of Middlesex, Gentle-
man, do hereby declare the nature of the said Invention for "IMPROVED
MACHINERY FOR CUTTING OR SHAPING METALS" to be as follows:-
This Invention relates to certain arrangements of machinery for shaping
articles in metal, applicable more particularly to the manufacture of fire-arms.
In manufacturing, for example, the lock frame of my improved fire-arms, I
employ the following description of tool for cutting the bevelled sides at one
and the same operation-Two. face cutters are mounted respectively on a
compound horizontal shaft, provided with driving pullies for giving rotary
motion to the cutters. Between these cutters the work is held fast, in such a
manner that the cutters may be brought in contact therewith. The cutter
shafts have their bearings in compound frames, which are capable of sliding in
the direction of their length on the bed of the machine.
The upper part of each compound frame is affixed to the under part by
centre pin, on which it is capable of turning to bring it to any required position

page_text: to suit the work in hand, and it is adjusted to and retained at any required
angle by a set screw, which also forms a connection between the two parts of
the frame. The cutters are caused to approach their work simultaneously by
means of suitable gearing (connecting the two cutter frames together), set in
action by a hand wheel. The cutter shafts are made in two parts, for the
convenience of throwing off the driving power.
In order to hollow out the lock frame for the admission of the working
parts, I submit the lock frame to the operation of what I term a universal
milling tool, which may be thus described: Fixed-to-the-top of a rectangular
frame are horizontal parallel guides for carrying a sliding frame, in which the
main driving shaft of the machine is mounted. This shaft, which is driven by
a band and pulley, forms also the cutter spindle. The traverse of the frame
over its guides is effected by a spur wheel driving two pinions or screws, which
turn in bearings in the main frame and pass through the sliding frame. On
one end of this spur wheel shaft is a bevil wheel, and at its opposite end.it is
provided with a hand wheel, for adjusting the position of the frame and bring-
ing up the cutter to its work. When this is effected, a mitre wheel on a
vertical shaft is thrown into gear with the bevil wheel on the shaft that carries
the spur and hand wheel. This vertical shaft passes through a hinged bar, by
vibrating which, the bevil wheels may be thrown out of gear, and it is driven
by a suitable arrangement of bands, pulleys, and gearing from the main
driving shaft or cutter spindle. In order to make a horizontal cut, the cutter
is brought up to its work by hand, and the mitre wheel of the vertical shaft is
thrown into gear; the rotary cutter will then slowly traverse over its work.
The work is carried by a vertical shaft, fitted with an index plate, for facili-
tating the adjustment of the work to an angle with respect to the cutter.
This shaft is carried by brackets from the side of the main framing, and it is
threaded at its lower end to admit of its rising without disturbing the position
of the spur wheel, which it carries. Through this wheel a vertical motion
(from a train of gearing actuated by a hand wheel) is communicated to the
vertical shaft, and thus the height of the work is changed by hand. The
fulcrum of the index finger is carried by an arm, which is supported by a
shoulder on the vertical shaft, which shaft passes through and may revolve
independently of the arm. At the opposite end to that which carries the
fulcrum pin, the arm-is-provided_with_an_anti-friction bowle, which works
against a guide bar. If this guide bar be inclined, and by means of a weighted-
chain the bowle be kept in contact with the guide bar, the vertical shaft, when
it is traversed up or down, will receive at the same time an axial motion, it
being drawn round by the index finger, which takes into the index plate keyed

page_text: to that shaft. A helical 'cut may by this means be put into the work when
required. For holding the lock frame 'under the action of the cutter, so that
the frame may be hollowed out to the irregular figure required, the following
contrivance' is adopted: A small bed plate, is attached to the top of the
vertical shaft, last mentioned, and on it are formed bearings for a horizontal
axle, which carries a swing frame; this axle is provided with a hand lever and
a ratchet wheel, into which latter a pawle attached to the bed plate takes, for
the purpose of holding fast the swing frame when required.
The work is secured in the swing frame, and is capable of being rolled under
the cutter by the hand lever.
The work is raised and lowered by the hand wheel, and. the arrangement of
gearing, before described. For piercing screw and other holes in the lock frame
and other parts of the arm, I enclose the work to be operated upon between
binged clamps, the upper one of which is composed of. hardened steel, and is
pierced with holes corresponding to the holes required to be bored; I then
apply the work to the action of rotating drills, causing the drills to pass
through the holes in the upper clamp and pierce the enclosed work.
For milling profile work, as the trigger guard and strap of the arm, I key
the work to a horizontal table, which slides in guides on the main framing of
the machine. This table at its under side carries a rack, which takes into a
pinion driven by a winch handle. On the face of this table beside the work a
guide piece is fixed. A vertical frame with parallel horizontal guide bars sup-
ports a compound sliding frame which carries spindles, having cutters at their
lower ends, and also tracer points or guide pins; these spindles are driven by
straps from a drum at the back of the machine, and they are capable of
receiving, together with the tracer points, a horizontal and a vertical motion
by means of a hand lever, which passes. through the compound frame and has
its fulcrum in the guide frame. The use of the tracers is to, traverse round the
guide piece, and thereby to cause their respective-cutters to describe a similar
figure while operating upon the work. The work and cutter being brought
into contact by means of the winch. handle of the table. and the lever of the
spindle frame, the workman, by this compound movement, keeps one of the.
tracers in contact with the guide piece, and, thereby the cutter is caused to cut
the work to the figure described by the tracer. It is convenient to mount two
kinds of cutters (with a tracer for each) on the spindle frame, in order that
the work may receive different kinds of cuts (for example, flat and convex-
cuts,) without 'requiring re-adjustment. The inner part of the compound
spindle frame is held fast to the outer part of the frame in its raised or
depressed position, as required, by means of a spring bolt.

page_text: For cutting the screws for the various parts of the fire-arm I employ the
following arrangement:-The screw blank is fixed in the end of a rotating
horizontal spindle, which is capable of sliding in its bearings; at its outer end
a screw thread is formed on this spindle, corresponding in pitch with that of
the screw to be cut, and taking into this thread is a threaded jaw, which is
carried by a hand lever that is keyed to an axle running parallel with the
spindle and furnished with a cutting tool, which stands in a line with the screw
to be cut. When the threaded jaw is brought into contact with the thread of
the spindle, the cutter is brought down upon the screw blank, and rotary
motion being imparted to the spindle, it will, by reason of the stationary jaw
taking into the thread, be caused to slide in its bearings and pass the screw
blank over the cutter, whereby a thread will quickly be formed thereon. The
head of the screw is formed by cutters, set at right angles to each other, and
driven forward by hand levers, the one to make the cross cut while the screw
is rotating, and the other the side cut.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Samuel. Colt in the Great Seal Patent Office on the
12th October 1854.
TO ALL TO WHOM THESE. PRESENTS SHALL COME, I, SAMUEL
COLT, of Spring Gardens, in the County of Middlesex, Gentleman, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of April, in the year of our Lord
One thousand eight hundred and fifty-four, in the seventeenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Samuel Colt, Her special license that I, the said Samuel Colt,
my executors, administrators, and assigns, or such others as I, the said
Samuel Colt, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make, use,
exercise, and-vend,-within-the-United Kingdom-of-Great-Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVED MACHI-
NERY FOR CUTTING OR SHAPING METALS," being partly a communication from
abroad, upon the condition (amongst others) that I, the said Samuel Colt,
by an instrument in writing under my hand and seal, should particularly
describe and ascertain the nature of the said Invention, and in what manner

page_text: the same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately after the
date of the said Letters Patent.
NOW KNOW YE, that I, the said Samuel Colt, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Drawings hereunto annexed, and to
the letters and figures marked thereon (that is to say): ==
This Invention relates to certain arrangements of machinery for shaping
articles in metal, which machinery is more particularly applicable to the
manufacture of my improved fire-arms. In Sheet I. of the accompanying
Drawings, I have shewn an improved construction of milling tool, which I
employ chiefly for shaping up the sides of my lock frame as it comes from the
forge hammer; but by fitting it with cutters of suitable form, two concave,
convex, or flat surfaces may be simultaneously produced, which flat surfaces
may either be parallel or at an angle to each other.
Fig. 1 is a front elevation of this improved cutting tool; Fig. 2 is a plan
view of the same; Fig. 3 is an elevation of the right-hand end thereof; Fig. 4
is a vertical section taken in the line 1, 2, of Fig. 2; and Fig. 5 is a section
taken in the line 3, 4, of the same Figure. a, a, is the main framing of
the machine, and upon it are mounted two adjustable beds b, b, to the under
side of which (projecting through slots in the top of the frame a,) the lugs
c, c, are bolted. These lugs are threaded to receive respectively the screw
shafts d, d, which turn freely in bearings provided for them in the framing.
To the outer ends of the screw shafts d are keyed the pinions d*, which gear
into pinions e', keyed to a shaft e. This shaft extends from end to end of
the machine, and passes through a central vertical shaft f, which is intended
to carry the work to be operated upon, and is capable of adjustment, ver-
tically, to bring the work to a proper level with respect to the position of the
rotary cutters. For this purpose the shaft f is threaded at its lower end, (see
Fig. 5,) and supported on a hollow axle g, which has its bearings in the main
framing. This axle has a female screw cut in it, corresponding to the thread of
the shaft f, and upon it is keyed a bevil wheel g', by turning which, either to
right or left, the shaft f will be raised or lowered, as desired. The adjustable
beds b, b, are each provided with a central projecting hub b', (see Fig. 6,
which represents one of these beds detached, and in plan view,) and also with
concentric slots 62. These beds are intended each to carry a frame h, in
which frames the shafts i that carry the rotary cutters are respectively
mounted in suitable bearings. The frames are secured to their respective

page_text: beds by screw bolts, which pass through the slots 6, and when the bolts are
slackened they are capable of being turned on their hub b', to set the cutters
at any required angle to their work. The cutters are composed of suitably
shaped pieces of steel k, set radially (as shewn in the detached view, Fig. 7)
in a face plate k', which is secured by the screws which hold the cutting edges
in place to a block k², having a centre hole tapped to receive the threaded end
of the shaft- Each of these shafts i is provided with a driving pulley i',
mounted loosely thereon; and when required to drive the shaft is brought up
and held in contact with a clutch (which is keyed to the shaft) by means
of a forked piece. This forked piece projects into a ring turned in the boss
of the driving pulley, and is affixed to a sliding bar on the top of the frame h,
which bar is operated by a handle, having its fulcrum on the frame-t; as
shewn at Fig. 2. The work to be operated upon is affixed to a table 1, 'carried
by a block m, which is secured to the shaft f; before mentioned. This table is
capable of receiving horizontal as well as vertical adjustment (which latter it
derives from the shaft f) to bring the work into position, and for this purpose
it is provided with an adjusting screw which turns freely in a lug attached
to the table, and enters a tapped hole in the block m. A hand wheel l² is
provided for rotating the screw and facilitating the horizontal adjustment of
the table; to this table a clamp or holder n is bolted, for holding the work
while under the action of the cutters.
.
The work shewn in Fig. 5, as secured to the holder, is a pistol lock frame,
which tapers towards its forward end; and its rear end has a semi-spherical
boss or projection. The cutters are suitably-shaped to mill or shape up the
opposite sides of this lock frame, which operation they are designed to effect
simultaneously. An opening is made in the holder n to receive the arbor-of
the breech cylinder, and wedges are also provided for securing the lock frame
in its holder. ¹ is a sliding piece, carried by the holder n, and actuated by a
cam and lever n; at its forward end it is slotted, to receive a wedge n³.
which bears upon the rear of the lock frame, and between the upper face. of
the icck frame and the sliding piece a forked wedge is hammered in, to hold
the work fast. When the work is to be discharged, the cutters are first
caused to recede, and the clamping cam is then turned to slacken the bite of
the wedges; the wedges-are-then-knocked out, and a plunger n is driven
forward, which strikes the end of the arbor of the lock frame and instantly
releases it. The arrangement of holder, it will be obvious, will differ, accord-
ing to the work to be operated upon. Supposing now the machine is required
to be started, the work is first properly secured in its holder, and it is then
brought by means of the screw shaft f, (which is raised or lowered by turning

page_text: the hand wheel g³ on the boss of the pinion g, which gears with the wheel g³,
before mentioned,) and also the adjusting screw of the table 1, into the
desired position between the cutters, which, to facilitate the setting up of the
work in the machine, are drawn back by means of the traversing screw shafts
d. When the work has been adjusted in its place by the means described,
rotary motion is given to the cutters, and they are caused to advance and act
upon the work. This advance is effected by turning the hand wheel, keyed
to a short axle, supported in bearings in the main framing, and carrying a
bevil wheel e, which gears into a bevil wheel on the shaft e.
The rotary motion thus communicated to the shaft e is transmitted through
the pairs of pinions e', d, to the screw shafts d, which, acting upon the
threaded lugs c of the sliding beds b, cause those beds to advance the cutters,
as explained. This forward movement of the cutters is continued until the
gauge screws (Fig. 1) of the sliding beds 6 strike against the main framing.
The hand wheel e is then reversed, and the cutters are thereby drawn back, to
permit of the work being discharged from its holder and replaced.
In Sheets II. and III. of the Drawings, I have shewn in several views an
improved arrangement of machinery, which I term my universal milling
machine.
This machine is provided with a variety of movements (one or more of
which may be in use at the same time) to enable it to perform the different
kinds of work which may be required. Thus, for example, I attach the
rotating cutter to a horizontal shaft, which admits of moving longitudinally in
its bearings, and will therefore pierce holes when required. This shaft I
mount on a traversing frame, which will carry the cutter forward or back-
ward at right angles to the sliding motion of the cutter shaft, and thereby
effect a straight cut like a planing machine. The work to be operated upon
I mount on a table, carried by a vertical shaft, to which I transmit when
required a vertical or an axial motion, intermittent or not, as required, or both
a vertical and axial motion. When this compound motion is given to the
work, the cutter (supposing it to be simply rotating) will make a spiral cut.
When an irregular cut is required, I mount the work upon a rocking frame,
which is carried by the vertical shaft, and by that means I am enabled to
produce repetitions of very irregular cuts with extreme precision and facility.
5 Fig. 1 is a side elevation of the machine; Fig. 2 is a plan view of the same;
Fig. 3 is a sectional elevation taken in the line 1, 2, of Fig. 1; and Fig. 4 is
a partial end clevation of the same. a, a, is the main framing, upon the top
of which rests a traversing frame b, mounted in suitable guides; this frame b
carries a spindle or cutter shaft c, which is rotated by means of a band, which

page_text: descends from the mill shafting, and passes round the driving pulley c¹. The
cutter shaft is socketted at one end to receive the shank of the cutter c
which is held securely therein by any suitable contrivance; at the opposite
end, this shaft. is connected by a ball and socket joint to a hand lever c, which
has an adjustable fulcrum c', in a slotted bracket c', affixed to the traversing
frame. This contrivance is for the purpose of traversing the cutter shaft in
its bearings, but when the longitudinal movement of the shaft is not required,
the lever is held fast by means of a clamping screw c. Mounted in suitable
bearings on the top of the framing a is a shaft d, which passes under the
traversing frame b, and carries at one end a hand wheel d', and at the other a
cog wheel d; this cog wheel gears into two pinions d, keyed to screw shafts d',
which have their bearings on the framing a, and pass through threaded lugs
carried by the traversing frame b. By the rotation therefore of the shaft d
by means of the hand wheel d', the forward or backward traverse of the
frame is effected; when this motion is required to be continuous it may be
obtained, without the assistance of the attendant, by the following means:-
e is a shaft, mounted in brackets attached to the, frame b, and to this shaft a
pulley is keyed, which receives motion from a band which passes round the
cutter shaft c. A bevil pinion e¹ keyed to this shaft e drives a bevil pinion,
which slides over a feather on a shaft e", and is secured to a rectangular
bearing piece e, through which both the shafts e and e² pass. The shaft e
carries a.pulley, from which proceeds a belt to a pulley on a shaft e*, turning in
bearings provided for it near the foot of the machine. Keyed to this shaft is
also a set of pulleys &', from which a belt proceeds to a set of pulleys e" on a
shaft e, situate at about the middle of the machine, and extending from end
to end thereof. The rotary motion of this shaft is communicated by a bevil
pinion on its end to a bevil pinion keyed to a vertical shaft f, which at its
upper end carries a bevil pinion f* in gear with a bevil pinion on the shaft d,
before mentioned, which shaft being thus set in motion will drive the screw
shafts d', and thereby effect the desired traverse of the frame b and its cutter.
In order to throw this motion out of action, the upper end of the vertical shaft
has its bearing in a lever f¹, jointed to the main framing at f, and connected
at its opposite end to a rod f³, the thrust of which will cause the lever to
assume the dotted position of Fig. 2, when the pinion will be thrown out-of
gear with the bevil pinion of the shaft d. I have said that the work to be
operated upon by the cutter is supported on a vertical shaft; this shaft is
shewn at g, and is capable of receiving an axial as well as a vertical motion.
It rests upon the pointed end of a screw g', which passes freely through a
bracket frame g² attached to the main framing a, and through the boss of a

page_text: spur wheel g', which is threaded to receive it, and constitutes its support.
Brass guides are provided for retaining the shaft g in its vertical position.
The vertical movement of the shaft is effected by turning a hand wheel g
keyed to a shaft g, the lower end of which carries a spur wheel g³, which,
through an intermediate spur wheel, drives the wheel g³ on the screw g', and
according to the direction of rotation of the wheel g³ the screw will be raised
or depressed, it being prevented from rotating therewith by reason of a screw
in the bracket frame g taking into a straight groove cut in the screw.
This vertical movement of the screw will raise or depress the shaft g, and
consequently the work which it carries can be adjusted to any required level.
The screw g is provided with adjustable stops to limit the amount of vertical
movement which the shaft g shall receive from the hand wheel g. Keyed
fast to the shaft g is a dividing plate h, and immediately beneath it a frame h¹
is loosely mounted on the same shaft. This dividing plate is provided with
rings of holes as usual to receive the pin h², which when in use imparts an
axial notion thereto, and consequently to the shaft g. An arm connected
to the frame carries this pin, and the other end of the frame is furnished
with an anti-friction bowle, which works in an adjustable guide * (see Fig. 4),
carried by a bracket attached to the main framing. It will now be understood
that when a vertical movement is imparted to the shaft g, and the pin h² is
dropped into a hole in the dividing plate, so as to connect it with the frame h¹,
and make their axial motion simultaneous, the bowle of the frame will be
forced up or down the guide , and according to the angle of inclination at
which the guide is set by its binding screw, so will the amount of axial motion
imparted to the shaft g be determined. The work to be operated upon is
carried by a suitable arrangement of clamp (constructed according to the nature
of the work) furnished below with a conical plug ', which fits into a socket
hole. formed in the top of the shaft g. At Fig. 1 I have shewn a barrel of my
improved pistol as under operation, a cutter being employed to shape up the
under part thereof. The barrel is held in position between a fixed and a move-
able rest attached to the clamp plate i, which has a conical plug , with a
flattened end that fits into a socket formed for it in the shaft g, as shewn
best at Fig. 3. To permit of the attachment of clamps having varying sizes of
plugs I use the arrangement represented at Figures 6, which shew one hollow
cone set within the other. Fig. 4 shews the machine arranged for making
helical cuts, and Fig. 5 is a partial plan view of the same. Fig. 7 shews in
vertical section, and Fig. 8 in plan view, so much of the machine as will serve
to explain the manner of grooving by means of the end thrust alone of the
cutter. In this instance, a slotted guide bar 7 is bolted to the cutter frame b,

page_text: and in the slot works a guide pin ', which is temporarily attached to the cutter
shaft c. The rotation of the cutter shaft is thus prevented, and it is caused to
slide in its bearings by vibrating the hand lever c³. It will be understood that
the cutters employed will in all cases be determined by the nature of the work
required to be performed.
The Figures in Sheet III. will serve to shew the manner of rocking the
work while under the action of the cutter. in order to produce an irregular
cut.
"
Fig. 1 shews in plan view a rocking holder supporting my pistol lock frame,
before referred to; Fig. 2 is the sectional elevation of the same taken in the
line 1, 2, of Fig. 1, and Fig. 3 is a side view taken at right angles to Fig. 2.
Figs. 4 shew detached parts of the holder i, which fits into the socket of the
shaft g.. To this table bracket arms m, which are affixed thereto and support a
crank shaft m³, to the crank of which a saddle piece m² is bolted, and between
the crank and saddle piece the lock frame is held fast, a socket being made in
the crank to receive the arbor of the lock frame. Keyed to the crank shaft is
a segment ratchet m³, and a hand lever m, and taking into the teeth of this
segment ratchet is a click me, attached to the table i. Supposing then the
rotary cutter to be brought to act upon the lock frame (to cut out the hollow
for the reception of the trigger arrangement), the work may be moved under
the cutter by the hand lever m*, the axis of the crank shaft being the centre of
the rocking motion. The segment ratchet may be made to indicate to the
attendant when the required amount of rocking motion has been imparted to
the work, by merely marking upon its face a line, which, coming under the
tooth of the click, shall be an indication that the cut is finished.
The Figures in Sheets IV. and V. shew an arrangement of machinery by
which I am enabled to mill the trigger guard and strap of my improved pistol,
and also other profile work, with great facility and economy.
Fig. 1, Sheet IV., is a side elevation of this improved machine; Fig. 2 is a
plan view of the same; and Fig. 3 is a front elevation, partly in section, the
better to shew its construction. a, a, is the main framing of the machine, the
standards b, b, of which carry a vertical rectangular frame c, c. The framing
a is provided with parallel guides, to receive and support a traversing table d,
which carries the work to be operated upon, and_also_a_pattern_of_the, work.
The fixed rectangular frame c carries a frame e, which is capable of sliding
horizontally over the face of that frame, and in the face of the frame e guides
are provided to receive the cutter frames ff, which are supported by bent
springs faffixed to the frame e. These springs are connected by links f² to
their respective cutter frames, and by their elasticity they have naturally a

page_text: tendency to keep the frames f in a raised position, so that the cutters which these
frames carry are out of contact with their work. The cutters are attached to
the vertical spindles g, which are supported in bearings affixed to their respec-
tive frames f. Keyed to each spindle g is a pulley g', round which a belt from
a driving drum gå, at the back of the machine, passes and imparts rotary motion
to the cutters. Spring bolts e¹ are attached to the front of the frame e, for the
purpose of locking into adjustable notched bars on the cutter frames, and
thereby retaining the frames at any required elevation; f³ are swivel sockets,
carried by arins f, projecting from the frames f; into these sockets is inserted
a lever f, the forward end of which enters a swivel socket c* carried by the
fraine C, and forming the fulcrum of motion for the lever. The use of this
lever is to direct the course of the cutter, which it is enabled to .do (either.
vertically or horizontally) by reason of the swivel sockets, which permit of its
moving in any required direction. Each cutter frame f is provided with a
tracer h, which is caused to move round the profile pattern on the table d, and
thereby control the movements of the cutter; i is the profile pattern, affixed to
a plate carried by the table d, and by its side the work k to be milled is placed,
as shewn in the plan view, Fig. 4. The work is held by a clamp, and at a
distance from the pattern corresponding to the distance between the cutter
and the tracer; when, therefore, the tracer is brought into contact with the
pattern, the rotating cutter will come in contact. with the work, and as the
tracer is caused to move round the pattern and describe a figure corresponding
to its outline, the cutter will perform. the like movement, and mill the edges of
the work.
The under side of the table d is provided with a double rack 7, into which
the wheels gear.
cog
.. These wheels are keyed to a shaft & having its bearings in the main framing,
and they are driven by means of pinions on the shaft l, also supported in
bearings in the main framing; keyed to the shaft is a cog wheel 1, into which
gears a pinion on the shaft of a winch handle F. In operating this machine,
the attendant, having fixed the pattern and the work on the table, as described,
and set the cutter rotating, withdraws the bolt el of that cutter frame which
he intends to employ, and brings down the cutter to the level of the work; the
bolt then springs forward and takes into another notch in the bar e, and
thereby retains the cutter at the proper level. The attendant then having hold
of both the lever f and the winch handle, traverses the tracer round the
pattern and the cutter over its work simultaneously, by giving a forward and
backward traverse to the table d through the gearing just described, and a
transverse sliding motion to the cutter frame.f through the hand lever. When

page_text: the cutter has performed its desired operation, and it is required to bring a finer
tool into action, or one having a different sectional figure, the hand lever fis
withdrawn from the socket of the cutter frame last in action, and set in the
socket of the adjoining frame f, and the cutter and tracer of that frame are, by
means of the hand lever.brought up to their work, the frame e for this pur-
pose being slidden laterally over the face of the fixed frame c. The shifting of
the tools is thus instantly effected.
It will be understood that a band from the drum g passes round the pulley
of each of the cutter spindles g, and that the object of having two cutter spindles
is to prevent the constant shifting of the cutters or of the work, that would
otherwise occur where both are rounded and a flat edge is required on the same
piece of work, as, for example, in the trigger guard and strap, shewn in the
Drawing.
For piercing screw and other holes in the lock frame and other parts of my
improved fire-arm, I employ the following contrivance, which is also applicable
to the boring of holes in metal generally-I enclose the work to be operated
upon between hinged plates, which form a clamp and hold the work firmly.
The upper plate is formed of hardened steel, and it is pierced with holes
corresponding in their relative position to the holes required to be bored. I
then apply the work to the action of rotating drills, and cause the drills to
enter the holes in the top plate and pierce the work that lies beneath.
By this contrivance, I am enabled to secure the greatest accuracy in the
positions of the holes, and that without the use of skilled labor to attend the
operations of the drills.
In Sheet VI., Fig. 1 shews in plan view, and Fig. 2 in edge view, this
novel construction of clamp for determining the position of the holes to be
bored; and Fig. 3 shews in elevation so much of the arrangement of drilling
machinery used in conjunction therewith as will serve to explain the mode of
operating. a, a, is a plate, from the upper face of which project pins or other
contrivance suitable for determining the position which the work shall take on
the plate. Jointed to this plate is the steel plate b, which is provided
with holes corresponding in position to the holes required to be bored in the
work.
(Fig. 1 shews a hammer as about to be operated upon).
The work before it is placed in the clamp is milled and filed to its proper
shape, and it is then dropped into the space provided for it between the plates a
and b. A clamping lever c jointed to the lower plate is then brought to bear
upon the plate b, as shewn, and the work is held securely. The clamp is then
placed on the table d, (Fig. 3,) of the drilling machine, and under the particular

page_text: drill required to be used, and the table being raised by a treadle motion, operated
by the hand or foot of the attendant, the work is brought in contact with one.
of the drills (all of which are kept rotating), and a hole is quickly bored. The
clamp is then shifted, and the same or another drill (as circumstances may
require) is caused in like manner to enter another hole in the plate b and
pierce the work. When all the holes required are pierced, the work may be
quickly disengaged from the clamp and replaced by another piece, and the
operation may be then repeated.
In Sheet VII. of the accompanying Drawings, Fig. 1 is a plan view of my
improved machinery for cutting screws; Fig. 2 is an elevation looking towards
the left hand end thereof; Fig. 3 is a longitudinal section taken in the.
line 1, 2, of Fig. 1; and Fig. 4 is a cross section taken in the line 3, 4,
of Fig. 1. a, a, is the bed plate of the machine mounted on a suitable cast-
iron frame b, b. c, c, is a hollow shaft, mounted in suitable bearings, carried by
the bed plate a, and upon which the driving pulleys d, d, are keyed. This
shaft c carries at one end a spring clip e, for holding the work to be threaded,
and at its other end it is provided with a screw f, of the pitch of the screw
desired to be cut. 9 is a rock shaft, mounted in bearings, carried by the bed
plate, and lying parallel to the shaft c. This shaft carries at one end an arm h,
to the under side of which a threaded jaw his secured. This threaded jaw is
intended to take into the worm or thread of the screw
while that screw is
rotating, and thus to impart a slow longitudinal motion to the shaft g, it being
suitably mounted, to provide for this movement. To the opposite end of the
shaft g to that which carries the threaded jaw an adjustable holder i is fitted,
for the purpose of carrying a cutter 2, which cuts the thread on the screw
blank.
This screw-cutting machine is shewn as arranged for turning and threading
the nipples of my improved fire-arms, and for this purpose it is provided with.
four cutters, which respectively gauge the diameter of the blank, finish off the
ends, cut the thread of the blank, and remove the thread from near the shoulder
of the nipple. A slot is formed in the bed a, for the passage through of the
clamping screws 1, 2, which hold the plate m in position after it has been
adjusted on the bed. This plate rests on parallel guides on the bed a, and
carries a slide rest n, to which the cutters n¹, n, are secured. The cutters are,
caused to approach their work and recede therefrom by means of a hand
lever o, which has its fulcrum at o' on the slide rest, and is jointed to a.
lever o, which has its fulcrum at 03 on the plate m.. A screw stop is.
provided at o, to limit the advance of the cutters and ensure a uni-
formity of operation. At the inner end of the plate m a dovetail groove. is

page_text: formed to receive a slide rest p, which moves at right angles to the slide rest n,
and carries a tool p¹ for trimming off the thread adjoining the shoulder of the
nipple. This slide rest is actuated by means of a crooked hand lever p², the
fulcrum pin of which is carried by a bracket from the plate m (see Fig. 4).
Keyed to the fulcrum pin is an arm p3 which is jointed to a connecting
lever paffixed to the slide rest; the rise therefrom of the lever p² will
cause the advance of the cutting tool p
The action of the machine is as follows:-A nipple blank, like that shewn
at 9, Figures 5, having been fixed in the spring clip e, and rotary motion
having been communicated thereto by a band on the pulley d, the cutters n', n²,
are first advanced by means of the hand lever o (the other cutters being in the
meanwhile out of action), and the blank is by these cutters prepared to receive
the thread. The direction of rotation of the shaft c is now reversed, and the
threaded jaw h¹ of the shaft g is brought down upon the rotating screw f, and
simultaneously the cutter is brought into contact with the nipple. The
continued rotation of the screw f gives the shaft g a traverse motion in the
direction of the arrow, Fig. 1, and causes the cutter to cut a thread on
the rotating nipple. When the tool' has arrived at the end of its course, the
workman lifts the jaw out of contact with the screw f, and slides back the
shaft with its cutter to the starting position, keeping the cutter in contact with
its work by forcing it out by means of the feeding screw of the adjustable
holder i, and this shifting operation he repeats until the required depth of
thread has been obtained. He then raises the cutter out of contact with
the work, and advances the cutter p' (shewn best in the enlarged view,
Figures 5,) by means of the hand lever p, at the same time reversing the
direction of rotation of the shaft c. This cutter p¹ is employed to turn a half
round groove close to the shoulder of the nipple, and thus by removing the
end of the thread causing the nipple to bed well on the breech cylinder.
The nipple is then released from the spring clip e by slackening the clamping
screw, and a fresh nipple being applied the-operation is repeated..
It will be understood that this machine is applicable to the cutting of screws
generally, the pitch of which will be determined according to the pitch of the
screw f, which screw is made removeable, that it may be readily replaced by
one of finer or coarser pitch,_to_suit_the_work_required.__
Having now set forth the nature of the Invention of "Improved Machinery
for Cutting or Shaping Metals," and explained the manner of carrying the
same into effect, I wish it to be understood that under the above in part recited
Letters Patent I claim,-
:
Under the first head of the Invention, the general arrangement of machinery

page_text: as described with reference to Sheet I. of the Drawings; and particularly
I claim the employment of adjustable rotating cutters for milling opposite
sides of the same piece of work simultaneously, in the manner substantially as
described.
With respect to the universal milling machine, forming the second head of
the Invention, I claim the arrangements of mechanical parts as described with
reference Sheets II. and III. of the Drawings, for effecting with facility
in one machine the various movements of the cutters and work, as above
specified.
With respect to the profile milling machine, I claim the general arrange-
ment of machinery as described, with reference to Sheets IV. and V. of the
Drawings.
Under the fourth head of the Invention, I claim the use of clamping
plates, or their equivalent, for determining the position of the drill cuts
upon the work under operation, in the manner and for the purpose above
explained.
Under the fifth and last head of the Invention, I claim the general arrange-
ment of parts above described, with reference to Sheet VII., and constituting
my improved screw-cutting machine.
And particularly I claim in relation thereto the combination of a threaded
jaw, or its equivalent, with a worm or screw thread affixed to the rotating
shaft which carries the screw blank, in the manner and for the purpose above
set forth.
In witness whereof, I, the said Samuel Colt, have hereunto set my hand
and seal, the Thirteenth day of September, in the year of our Lord
One thousand eight hundred and fifty-four.
SAM. COLT. (L.S.)