Improvements in the Manufacture of Metal Tubes,
Year: 1899

page_text: Date of Application, 2nd May, 1899-Accepted, 10th June, 1899
Improvements in the Manufacture of Metal Tubes,
I, FRANK ASHLLEY WILMOT, of No. 319. Clinton Avenue, Bridgeport, Fairfield
County, Connecticut, United States of America, Manufacturer, Inventor, do
hereby declare the nature of this invention, and in what manner the same is to
he performed to be particularly described and ascertained in and by the following
statement:-
"
My invention relates to metal tubing adapted for general use and especially
adapted for use in the manufacture of bicycle frames, bayonet scabbards and
other articles formed from iron or steel tubing, it not being essential so far as
the principle of my invention is concerned that the tubing he, produced in any
special manner, as for example in carrying out my invention the tubing may be
ordinary drawn tubing or jointed tubing of any ordinary grade, or it may be
tubing of the kind known to the trade as Clincher tubing that is tubing
formed from a strip of sheet metal having upon its edges interlocking projections
and recesses, said edges being closed together by circumferential compression
so that in certain of the teeth metal is displaced laterally in alternate opposite
directions causing the teeth on the opposite edges to clinch firmly as fully set
forth and claimed in British Letters Patent No. 6824 granted to me March 16,
1897, and my present invention has for its object to produce a tube of this
character which shall he moisture proof from the inside, water tight at the joint,
which will take the solder readily in brazing flush joints and which will take an
enamel upon its outer side and hold it so that blistering shall be prevented.
In the accompanying drawing forming part of this specification.
Figure is a perspective illustrating my novel tubing in the process of
manufacture the tube having been dipped and being covered interiorly and
exteriorly with a coating of non oxidizable metal.
Fig. 2 a similar view illustrating the operation of grinding off the outer coating.
Fig. 3 an end view on an enlarged scale illustrating the tube as in Fig. 1.
that is after being dipped or otherwise coated interiorly and exteriorly with non
oxidizable metal.
Fig. 4 a similar view illustrating the completed tube that is to say the outer
coating of non oxidizable metal having been ground off in order to finish the tube
and the joint, the joint in fact being barely visible in the tubing as finished for
shipment or use, and
Figs. 5 and 6 are perspectives illustrating the principle of my invention as
applied in connection with flat sided tubing and illustrating different well known
styles of interlocking joints and also showing tubes made from a plurality of
pieces or strips of metal, that is, having a plurality of joints.
It is of course well understood that in the manufacture of bicycle frames it
is found practically impossible in assembling the parts to prevent moisture from
getting into the tubes. It has been a serious objection to all classes of tubing
heretofore used in the manufacture of bicycle frames that moisture within the
lubes would cause oxidation of the tubes from the inner side, frequently causing
the enamel to blister and flake off and sometimes completely destroying the

page_text: Anoiber
integrity of the tubing so that the bicycle became liable to brenk in use with
serious results to the rider. This objection wholly overcome by dipping the
tubes without any polishing or finishing whatever in a suitable molten non
oxidizable metal or alloy, for example brass whereby a coating of the non
oxidizable metal is formed both on the interior and exterior of the tubes. Other
important advantages which result from dipping the tubes in molten mon
oxidizable metal or alloy are that the interstices of the joint are completely
filled with the molten metal which solders the joint in the most effective manner
possible and makes the tubes for all practical purposes solid tubes.
advantage is that the inner coating of non oxidizable metal makes a perfect
preparation without any additional operations for brazing flush joints as in putting
the parts of a bicycle frame together, and another very important advantage is
that the enst of final grinding of the tube is found to be greatly reduced by the
coating of oxidizable metal which is ground off in the intuner
that tube is ordinarily ground for the purpose of polishing but it is
found in prnotice that when coated with another metal a very fine finish
may he produced upon the tubes by grinding much more easily and quickly,
than if the tubes are ground without dipping in molten metal.
A denotes the tube which may be of iron or steel and may be a drawn tube
or a jointed tube of any style although I preferably use in making my novel tubing
steel tubes of the well known clincher type, that is tubes formed from blanks
or strips of sheet metal having upon their edges interlocking projections and
recesses said edges being closed together by circumferential compression so that in
certain of the teeth metal displaced laterally in alternate opposite directions
causing the teeth on the opposite edges to clinch firmly. It will of course be
apparent that the tubes may be formed from a plurality of pieces or strips of
metal, and of any desired forin in cruss section. B denotes an inner coating of any
suitable non oxidizable metal or alloy which comprises part of the finished
tubing and an outer coating of the same metal which is placed upon the tube
simultaneously with the inner coating, preferably by dipping the entire tube
in molten metal or alloy, but which is wholly ground off in the final process of
polishing and finishing the tube for shipment or use it being of course understood
that tubing of this chameter after being manufactured into articles, as bicycles, is
ordinarily finished exteriorly by japaning of the quality commonly known as
enamelling and that this finish requires that the iron or steel tubes upon which
it is placed should be thoroughly cleaned and polished. The grinding or
polishing of the tubes may be effected in any preferred manner as by a grinding
wheel D.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
1. The method of finishing metal tubing which consists in coating the tubes
hoth interiorly and exteriorly with a non oxilizable metal or alloy and then
grinding off the coating from the exterior of the tubes, substantially as and for
the purposes set forth.
2. The method of finishing sheet metal tubing which consists in dipping the
tubes in molten non oxidizable metal or alloy whereby a non oxidizable metallic
coating is formed interiorly and exteriorly of the tubes and then finishing the
tubes by grinding off the coating from the exterior thereof.
8. The method of making and finishing sheet metal tubing which consists
in providing each edge of a blank of sheet metal with a series of interlocking
projections and recesses. then closing said edges together, then dipping the tube
in molten non oxidizable metal or alloy whereby the interstices of the joint are
filled and the edges are soldered tightly together and then finishing the tube by
grinding off the coating from the exterior thereof.
4. The method of making and finishing sheet metal tubing which consists in

page_text: providing each edge of a blank of sheet metal with a series of interlocking pro-
jections and recesses, then closing said edges together by circumferential com-
pression so that metal of certain of the teeth is displaced laterally in alternate
opposite directions then dipping the tube in molten non oxidizable metal or alloy
whereby the interstices of the joint are filled and the edges are soldered tightly
together and then finishing the tube by grinding off the coating from the
exterior thereof.
5. As a new manufacture, a butt jointed iron or steel tube dipped in a non
oxidizable metal or alloy and having its outer surface ground smooth.
6. A tube formed from a blank of sheet metal having upon its edges inter-
locking projections and recesses. the edges of said blank being closed together
and forming a butt joint, the said tube being dipped in a non oxidizable metal or
alloy, and the interstices of the joint thus filled with said metal or alloy whereby
the edges are soldered and the tube made integral, said tube having its exterior
ground smooth.
7. As a new manufacture an iron or steel tube having its inner surface coated
with a non oxidizable metal or alloy and its outer surface ground smooth.
S. A tube formed from a blank of sheet metal having upon its edges inter-
locking projections and recesses the edges of said blank being closed together, the
interior of said tube being coated with a non oxidizable metal or alloy, the inter-
stices of the joint being filled with said metal or alloy whereby the edges are
soldered and the tube made integral, and the exterior of said tube being finished
by grinding.
9. A tube formed from a blank of sheet metal having upon its edges inter-
locking projections and recesses the edges of said blank being closed together
by circumferential compression so that the teeth upon the respective edges will
be caused to clinch, the interior of said tube being coated with a non oxidizable
metal or alloy, the interstices of the joint being filled with said metal or alloy
whereby the edges are soldered and the tube made integral and the exterior of
said tube being finished by grinding.
Hotel this out law of M 1800