AN IMPROVED TOOL FOR ENLARGING HOLES IN SHEET AND OTHER METAL
Year: 1864

page_text: LETTERS PATENT to John Bowns, of Earlestown, near Warrington, in the
County of Lancaster, for the Invention of "AN IMPROVED TOOL FOR
ENLARGING HOLES IN SHEET AND OTHER METAL."
Sealed the 12th July 1864, and dated the 20th January 1864.
PROVISIONAL SPECIFICATION/left by the said John Bowns at the Office
of the Commissioners of Patents, with his Petition, on the 20th January
1864.
I, JOHN BOWNS, of Earlestown, near Warrington, in the County of Lan-
5 caster, do hereby declare the nature of the Invention for "AN IMPROVED TOOL
FOR ENLARGING HOLES IN SHEET AND OTHER METAL," to be as follows:-
This Invention has for its object an improved tool for enlarging holes in
sheet and other metal. In constructing iron ships, boilers, and similar
structures it is usual to punch the holes in the plates of metal before putting
them together, and where the holes in two plates do not exactly coincide they
are made to do so, as far as possible, by driving a taper steel plug hardened
and tempered through the holes, this tool is called a "drift."
Now, according to my Invention, in place of making the drift merely a plain
cone of steel which acts only to squeeze the metal out of the way, I make the
drift with cutting edges, so that when it is driven in it may cut away and
detach the metal which impedes its passage. I produce the cutting edges
by forming a spiral groove around the drift so as to leave a cutting edge or
ridge winding around it from end to end. The cutting face of the ridge is

page_text: vertical or nearly so to the side of the hole to be cut, and the back of the
ridge inclines off gradually. The tool above described may be used not only
as a drift to bring two holes to coincide, but also to rime or enlarge a hole
in a single sheet or piece of metal, the tool being forced through the hole by
pressure or impact. If desired the tool may be caused to revolve whilst it is
employed for enlarging a hole, and this may be done by mounting it in a
lathe
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Bowns in the Great Seal Patent Office on the 20th
July 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
BowNs, of Earlstown, near Warrington, in the County of Lancaster, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twentieth day of January, in the year of our
Lord One thousand eight hundred and sixty-four, in the twenty-seventh year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said John Bowns, Her special licence that I, the said John Bowns,
my executors, administrators, and assigns, or such others as I, the said
John Bowns, 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 "AN
IMPROVED TOOL FOR ENLARGING HOLES IN SHEET AND OTHER METAL," upon the
condition (amongst others) that I, the said John Bowns, 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 Bowns, 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 thereof, that is to say:-

page_text: and tempering, and in the larger sizes I do not continue the taper from end
to end, but make the tool parallel at the upper end for a distance of half a
diameter or more to ensure perfect truth in the work. Figure 3 is a side
view, and Figure 4 an end view, of a drill with a rimer such as I have
described on its stem, this rimer is very slightly tapered, and at its end it is
formed into a drill, it is worked in a drilling machine, lathe, or otherwise, like
an ordinary drill, and the holes which it makes will be formed very true and
smoothe. Figure 5 is a side view, and Figure 6 is an end view of a rimer
which is made hollow to fit on to a boring bar mounted in a lathe, it is
prevented revolving on the bar by a key; it is by preference cut away at the
end on each side as is shown, and like an ordinary cylinder drill this facilitates
the entry of the tool as the work is taken up to it by means of the saddle or
slide of the lathe; should the hole require to be much enlarged, it is desirable
to mount an ordinary boring cutter on the bar in advance of the rimer to
bring the hole nearly to the required size.
In witness whereof, I, the said John Bowns, have hereunto set my
hand and seal, this Eighteenth day of July, in the year of our Lord
Lord One thousand eight hundred and sixty-four.
JOHN BOWNS. (LS.)