IMPROVEMENTS IN TOOLS, CUTTERS, AND HOLDERS THEREFOR, AND IN OTHER APPARATUS EMPLOYED IN DRILLING, BORING, FACING, RECESSING, TURNING, AND CUTTING
Year: 1871

page_text: LETTERS PATENT to John Snowdon, of 65, Saxton Street, New
Brompton, in the County of Kent, Engineer, for the Invention of
“IMPROVEMENTS IN TOOLS, CUTTERS, AND HOLDERS THEREFOR, AND IN OTHER
APPARATUS EMPLOYED IN DRILLING, BORING, FACING, RECESSING, TURNING,
AND CUTTING."
Sealed the 30th May 1871, and dated the 14th January 1871.
PROVISIONAL SPECIFICATION left by the said John Snowdon at the
Office of the Commissioners of Patents, with his Petition, on the
14th January 1871.
I, JOHN SNOWDON, of 65, Saxton Street, New Brompton, in the
County of Kent, Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN TOOLS, CUTTERS, AND HOLDERS THEREFor,
AND IN OTHER APPARATUS EMPLOYED IN DRILLING, BORING, FACING, RECESSING,
TURNING, AND CUTTING," to be as follows:-
The first part of my Invention relates to the tools or cutters employed
in the processes of drilling, boring, facing, recessing, turning, and

page_text: cutting, and in the holders to be used therewith, and consists in a novel
mode of constructing and arranging the said tools or cutters, and the
holders therefor, whereby a large saving of steel is effected in their
manufacture; also in the mode of fixing the said cutters in the holders;
and in the means for preventing said tool holders from turning in the
sockets or chucks of the machines in which they are employed.
This part of my Invention is specially applicable to cases wherein
what is known as a pin drill or centre bit might be employed.
My improved tool or cutter holder is made by preference of wrought
iron or malleable cast iron with a shank to be inserted and fixed in the
socket or chuck of the drilling, boring, or other machine by which it is
made to revolve. At the end of the said chuck I form one or more arms
projecting at right angles therefrom in which are made suitable recesses
to receive the separate tools or cutters intended to operate on the
material under treatment. I prefer to arrange these cutters (which are
made of steel) in the tool holder in such a manner that they shall act by
successive steps, the outermost cutter being somewhat farther advanced
than the others in order that the material shall not first be removed
from the centre, thereby preserving to the last moment the guiding
power of the central guide pin or drill, which I place and secure in a
hole drilled up the centre of the tool holder instead of forming it as
commonly done heretofore solid with the steel tool or cutter. I fix the
separate tools or cutters in the recesses of the tool holder by means of
wedges, which I prefer to make of half round iron.
In some cases it is convenient to form the tool holder with a boss 2
instead of arms as above mentioned provided with a recess or recesses to
receive the tools or cutters, and provision is made for the insertion of the
retaining wedge in each case. When necessary I prevent the tool holder
from turning in the socket or chuck of the machine in which it is used
by forming a groove or recess across the face of such socket or chuck, 3
and making the shank of the tool holder with one or more arms adapted
to take into the said groove on the socket or chuck, by which means it
is forced to turn therewith more certainly than when dependant only
upon a set screw or feather as heretofore employed.
The second part of my Invention relates to apparatus to be applied to 3
a drilling machine or lathe for the purpose of turning bolts, studs, screw
blanks, or other similar articles, certain parts of the improvements
referred to under the first head of my Invention being applicable thereto.

page_text: $
I employ in connection with a drilling machine or lathe a plate with
one or more holes in it of the size or nearly so of the intended bolt,
stud, or screw blank, the said plate being fixed in a plane at right
angles to the spindle of the drilling machine or lathe with the centre of
one of the holes in the plate in line with the said spindle. Small steel
cutters of suitable shape are fixed (preferably by means of wedges in the
manner before referred to) in slots or grooves cut in the plate and
radiating towards the holes, the cutting edges of said cutters projecting
inwards beyond the circumferences of the holes. The bar or rod of
material to be operated upon is fixed in the socket or chuck of the
drilling machine or lathe, and being made to revolve the end of the bar
or rod when forced into the hole in the plate will be turned or shaped in
the desired manner by the cutter belonging to that particular hole in a
more expeditious manner than heretofore. A moveable cutter is mounted
on an arm swivelling on the plate and may be used to cut off the
bolt, stud, or screw blank, when the turning is in other respects
finished.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Snowdon in the Great Seal Patent Office on
the 13th July 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
SNOWDON, of 65, Saxton Street, New Brompton, in the County of Kent,
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of January, in the year
of our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Snowdon, Her special licence
that I, the said John Snowdon, my executors, administrators, and
assigns, or such others as I, the said John Snowdon, 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 "IMPROVEMENTS IN

page_text: TOOLS, CUTTERS, AND HOLDERS THEREFOR, AND IN OTHER APPARATUS EMPLOYED
IN DRILLING, BORING, FACING, RECESSING, TURNING, AND CUTTING," upon the
condition (amongst others) that I, the said John Snowdon, my executors
or administrators, by an instrument in writing under my, or their, or
one of their hands and seals, should particularly describe and ascertain
the nature of the said Invention, and in what manner 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 John Snowdon, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement, reference being had to the accompanying Drawings
hereunto annexed :-
The first part of my Invention relates to the tools or cutters employed
in the processes of drilling, boring, facing, recessing, turning, and
cutting, and in the holders to be used therewith, and consists in a novel
mode of constructing and arranging the said tools or cutters and the
holders therefor, whereby a large saving of steel is effected in their manu-
facture;
also in the mode of fixing the said cutters in the holders; and in
the means for preventing said tool holders from turning in the sockets
or chucks of the machines in which they are employed.
This part of my Invention is specially applicable to cases wherein
what is known as a pin drill or centre bit might be employed.
My improved tool or cutter holder is made, by preference, of wrought
iron or malleable cast iron with a shank to be inserted and fixed in the
socket or chuck of the drilling, boring, or other machine by which it
is made to revolve. At the end of the said shank I form one or more
arms projecting at right angles therefrom, in which are made suitable
recesses to receive the separate tools or cutters intended to operate on
the material under treatment. I prefer to arrange these cutters (which
are made of steel) in the tool holder in such a manner that. they shall
act by successive steps, the outermost cutter being somewhat farther
advanced than the others in order that the material shall not first be
removed from the centre, thereby preserving to the last moment the
guiding power of the central guide pin or drill, which I place and secure.
in a hole drilled up the centre of the tool holder instead of forming it,
as commonly done heretofore, solid with the steel tool or cutter.
I fix

page_text: the separate tools or cutters in the recess of the tool holder by means of
wedges, which I prefer to make of half round iron or steel.
In some cases it is convenient to form the tool holder with a boss
instead of arms, as above mentioned, provided with a recess or recesses
to receive the tools or cutters, and provision is made for the insertion
of the retaining wedge in each case. When necessary I prevent the
tool holder from turning in the socket or chuck of the machine in which
it is used by forming a groove or recess across the face of such socket
or chuck and making the shank of the tool holder with one or more
arms adapted to take into the said groove on the socket or chuck, by
which means it is forced to turn therewith more certainly than when
dependant only upon a set screw or feather, as heretofore employed.
The second part of my Invention relates to apparatus to be applied
to a drilling machine or lathe for the purpose of turning bolts, studs,
screw blanks, or other similar articles, certain parts of the improvements
referred to under the first head of my Invention being applicable
thereto.
I employ in connection with a drilling machine or lathe a plate with
one or more holes in it of the size or nearly so of the intended bolt,
stud, or screw blank, the said plate being fixed in a plane at right angles
to the spindle of the drilling machine or lathe with the centre of one
of the holes in the plate in line with the said spindle. Small steel
cutters of suitable shape are fixed (preferably by means of wedges in the
manner before referred to) in slots or grooves cut in the plate and
radiating towards the holes, the cutting edges of said cutters projecting
inwards beyond the circumference of the holes. The bar or rod of
material to be operated upon is fixed in the socket or chuck of the
drilling machine or lathe, and being made to revolve, the end of the bar
or rod when forced into the hole in the plate will be turned or shaped
in the desired manner by the cutter belonging to that particular hole
in a more expeditious manner than heretofore. A moveable cutter is
mounted on an arm swivelling on the plate and may be used to cut off
the bolt, stud, or screw blank when the turning is in other respects
finished.
In Sheet 1 Fig. 1 represents a front view partly in section, a side
view, and view of under side of a tool holder and cutters constructed
in accordance with the first part of my Invention, and which is suitable
for drilling and recessing at same time. The tool holder A I prefer to

page_text: •
make of wrot iron or malleable cast iron. It is made with a pro-
jecting part or arm B in which is formed a recess C, which I prefer to
place obliquely with regard to the centre pin or drill, as shown. The recess
receives the steel cutter D (shown in dotted lines in the front view and
removed from the recess in the view of under side), which is secured
therein by the half round wedge E. F is the central pin or drill secured
by a set screw or otherwise in a hole drilled up the centre of the tool
holder. The upper end of the tool holder is adapted to fit into the
drill box or chuck of a drilling machine or lathe, the tail piece G formed
on the upper end taking into the rectangular slot therein is driven by
it in the ordinary manner.
Fig. 2 represents a partial section, side elevation, and under side view
of a similar tool holder and cutters adapted to cut holes in the tube
plates of boilers, holes for ship work, and other similar purposes.
Similar letters of reference refer to the similar parts of Fig. 1. The
cutters are arranged to cut an annular groove, the central drill steadying
the holder as the work progresses. They may be adjusted to cut holes of
various sizes by being moved in the recesses to or from the centre and
fixed in any required position by wedges E and packing strips E' as
shown in full lines in under side view, or if preferred by means of set
screws, as shown in dotted lines. In this example two arms B, B, are
shown, but any other convenient number may be used as the dimensions
or character of the work may require.
Fig. 3 represents similar views of a tool for drilling, facing, and
recessing, the centre drill, cutters, and wedges being shown in dotted
lines, which also show how the sizes and positions of cutters may be
regulated to suit a certain range of sizes of holes, the outermost cutter
being the most advanced when it is intended to cut through, say, a plate
so as to retain to the last moment the guiding power of the central guide
pin or drill. In order to compensate for the wear of the central drill the
bolt and long nut H may be inserted loosely in the central hole above
the drill. As the drill wears the bolt may be unscrewed more or less
from the nut, and the cutting edge of drill thus kept out to the proper
distance.
This Figure also illustrates the method I employ for preventing the
tool holder from turning in the socket or chuck of the machine in which
it is used. I is a cross head formed in one piece with the tool holder,
intended to take into a recess formed across the face of the socket or

page_text: chuck, the sides of which acting against the cross head releive the set
screws from any strain, so that they are only required to prevent the
tool holder from falling out of the socket.
Fig. 4 represents similar views of a quadruple boring tool or one
with four arms, and corresponding cutters placed at successive distances
from the centre. In this Figure the cross head referred to in Fig. 3
is made loose and adapted to fit on to the hexagonal or squared part J
of the tool stem. The cross head is made moveable to allow of a boss
being slipped on to steady the tool, or a rose bit as shown in dotted
lines to clean out the hole and at same time to steady the tool when
cutting angular holes, or of an archimedian screw to remove cuttings
when drilling and countersinking are being done at the same time.
The central guide drill is here shown fixed by a wedge or key K, and
the drill stem has a corresponding flat filed on it. It is important in
these tools that the cutting edge of the central drill should stand
approximately in line with two opposite cutters, but by the wear
and consequent sharpening the said cutting edge gradually assumes a
cross position and the drill also wears down in length. When this
occurs it can by this arrangement be removed, turned round a little
to bring it again into the required position with regard to cutters,
and another flat filed higher up and further round for the wedge or
key to act against to keep it in that position; L is a slot in the tool
holder shank in which a cutter may be placed to countersink the hole
as it is being drilled by the cutters in the arms. This countersinking
cutter may be applied, when required, to any of this class of tool holder.
This tool is specially adapted to drill holes in armour plates, or for other
purposes wherein great sizes and depths are required..
.
4
Fig. 5 represents elevation and under side view of a pin or nipple drill
adapted for facing or recessing, and showing the application of set
screws to regulate the cutters. A drill, rose bit, plain drill, or conical
centre point may be used in the centre to suit circumstances, and in
some cases the pin may rotate with the holder in a shallow hole in the
material without advancing therein while the tool holder and cutters
slip down over it whilst cutting, a key or set screw being applied to bind
it moderately tight in the central hole of the tool holder. By this means
a great amount of material may be removed from large forgings without
leaving a deep centre hole. The same arrangement of loose and sliding
centre pin is applicable to all the tools of this class herein described.

page_text: In Sheet 2, Fig. 6 represents part sectional elevation of a tool for
rounding heads and points of bolts in a drilling machine, screwing
machine, or lathe. It acts either by revolving the work and fixing the
tool or vice versa. It is also specially suitable for such work as forming
pintles on rudders for iron vessels, and in this case instead of a semi-
spherical hole as shown a cylindrical hole of the required length of pintle
is continued up the tool with the cutter inserted; in a similar manner
the tool is made to revolve by suitable machinery and is forced on to
the solid iron upon which it forms a pintle of the size required. D is
the cutter E, the holding wedge or key; L, a hole communicating
with the lubricating cup M. by which a supply of lubricating material
can easily be applied to the cutting edge.
Fig. 7 represents a tool for cutting holes in wood or iron or for making
trenails, wooden plugs for decks, or other short cylindrical pieces. The
cutters D and D', which are of a dovetailed form on one side, are fixed
in the recesses which are formed on the outside of the arms B, B¹, and
secured therein by keys in a similar manner to that before described.
It will be observed that the cutter D is adapted to cut on the outside,
and the cutter D on the inside, thus one tool clears the other through
great depths for boring purposes. A centre pin or drill may be used
with this modification as with those before described.
Fig. 8 represents a centre bit for use in boring wood, and will be
readily understood from the preceding descriptions. A plain pin or an
augur bit may be used in the centre as may be required.
. Fig. 9 shows the application of the cross head described in reference
to Fig. 3 to the fixing and driving of drilling sockets for large or
small work, the Figure showing several sockets fitted one into the other,
all strain being taken off the set screws by the said crosshead, except that
necessary to keep the sockets from dropping out. This is especially useful
in large boring bars where the single tail piece, such as G in the Figure,
is insufficient.
Fig. 10 is a half section and elevation, and Fig. 11, half plan and
section of a cutter block for moulding, tenoning, planing, and other
wood working machines, showing the application of the half round
wedge to fixing the cutters and the placing of such cutters in recesses,
thus keeping the cutters solid and avoiding the necessity of cutting slots
. in them as heretofore practised. The wedges may be set up by a screw
and nut as shown or otherwise.

page_text: Instead of the arms mentioned in the foregoing description, in some
cases a simple boss may be employed, the necessary recesses being formed
therein in the same position relatively to the centre.
The Figures on Sheet 3 illustrate the second part of my Invention.
All the letters of reference refer to like parts in each of the Figures.
In Figures 12 and 13, A is the cutter plate, in which are formed
several holes B, B, &c., of various sizes to suit the work required; C, C,
&c., steel cutters fitted into recesses in the plate, the cutting edges
project inwards beyond the circumferences of the holes. The cutters are
fixed in position by the wedges or keys D, D, at their sides, and are fed
forward as required by similar wedges or keys E, E, at their ends; F, F,
are slots to facilitate the escape of the cuttings. The upper side of the
plate is shown with the holes made conical for a part of their depth, and
the cutters bevilled to the same angle; in these holes screw blanks with
the ordinary conical heads can be made. On the other side of the plate
the holes are shown recessed and cutters adapted to them to suit. In
these holes when the plate is recessed screw blanks with cheese heads
may be made. The plate A is attached by a central bolt or otherwise
to a movable table & sliding on the bracket G', which is itself fixed. to
a drilling machine, screwing machine, or lathe, so that the hole of the
size required for the intended work shall come centrally in line with
the drill, screwing, or lathe spindle, in the chuck of which the bar
or rod of material to be operated upon is fixed. The material being
made to revolve the end of the bar or rod when forced into the hole
in the plate will be turned or shaped in the desired manner by the
cutter belonging to that particular hole. When the turning is com-
plete the rod is removed from the hole and brought into the necessary
position to be cut off by the cutter H fixed in the slide I operated
by the handle J. The bar or rod is steadied in its revolutions while
being cut off by the V pieces K, K, fixed in the upper part of the
bracket G. If desired the thread may be formed on the stud or bolt
before being cut off the bar or rod by means of the screwing apparatus
shown in Figures 14 and 15, and at L on the upper part of Figure 13,
the screwing dies in Figure 14 being drawn back by the spiral plate in
Figure 15, which is moved round by the handle M seen in Figure 13
while the turning and cutting off is proceeding, and pushed forward
thereby so as to cut the thread when the stud or bolt on end of bar is
brought into position to be acted upon by them.
.

page_text: Tools for boring large holes, or for facing, recessing, or cutting large
surfaces in armour plates, guns, ship or bridge work, machinery, and
other similar purposes, constructed in accordance with my Invention,
require very much less steel, breakages are less frequent, repairing and
sharpening less expensive, and the power required to drive and feed
them forward much less than in the tools heretofore usually employed
for such purposes.
Having now described the nature of my said Invention, and the
manner in which the same is to be performed, I would have it under-
stood that what I claim as my Invention is,―
First. Tools for boring, facing, recessing, turning, and cutting con-
sisting of a tool holder with one or more arms or bosses formed with
oblique or radial recesses in which movable steel cutters are fixed, the
whole constructed, arranged, and applied substantially as described and
shown.
Second. Fixing the steel cutters in the recesses of tool holders con-
structed as herein described by means of half round wedges or keys as
described and shown.
Third. The use of a central guide in such tool holders (which may
turn therewith or not) on which the said tool holders are capable of
sliding while cutting, substantially as described and shown.
Fourth. The use of arms or a cross head and a slot across the face of
the chuck into which the said arms or cross head is applied for driving
such tools in the chucks or for driving the chucks themselves, sub-
stantially as described and shown.
Fifth. The perforated turning plate with recesses containing cutters
fixed therein by half round wedges or keys constructed and applied
substantially as described and shown.
In witness whereof, I, the said John Snowdon, have hereunto
set my hand and seal, this Twenty-eighth day of June, in the
year of our Lord 1871.