How to make copper trays (used for pins, hair pins, cards, etc.).
(1) Round. (2) Square or oblong.
[Illustration: ROUND TRAY]
_Material:_ Piece of copper about 7 ins. square, No. 20 gauge. A hard
wood block, 10 × 10 × 2 ins. thick. _Tools:_ Carpenters' gouge chisel,
dividers, steel punch, shears, round peg of wood, 6 ins. long and 1 in.
in diameter.
[Illustration]
_Design:_ Take a large sheet of plain paper. Draw on it a 3-in. circle.
Using the same centre, draw a 5-in. circle. This gives you the plan
or top view of the tray. Below this view on the same sheet, draw the
elevation, or edge view of the tray. You can make the tray as deep in
the centre as you wish. Let's make this one 1/2 in. deep, that's a good
proportion.
[Illustration: Hard wood peg]
This is what we call a working drawing. If you are pleased with the
design, you can go right on with the work, if not, you can change it
to suit. You can see by the design that the tray is made by driving
the centre of this square plate of copper down into a depression. In
order to do this we must make a mould the exact size and shape of the
tray centre. This is what the square hard wood block is used for.
[Illustration]
[Illustration]
Take your hard wood block. Draw diagonal lines across one face. Where
these lines intersect is the centre. With your dividers, using this
centre, draw a 3-in. circle. Place the carpenters' chisel anywhere on
the circle and strike with a hammer, driving the chisel down into the
wood about 3/8 in. Do this all around the circle. Gouge out the loose
wood until you have cleaned out the whole depression, being careful
not to go below 1/2 in. in depth (the depth of your design). Smooth
this up nicely with sand-paper. The mould is now ready for the metal
plate. With the steel punch, make holes in each corner of the copper
plate about 1/2 in. from the edge and just large enough to fit the wire
nails. Place this plate over the mould so that the centre of the plate
comes right over the centre of the mould. Fasten the four corners down
with the wire nails. To drive the metal into the depression we must use
something softer than a steel hammer. A hard wood peg has been found
to do this best. Cut a piece about 6 in. long from the end of a broom
handle. Round one end up, using a file or a carpenters' chisel to do so.
[Illustration]
Place the rounded end of the peg on the circle of the copper plate
and, with a hammer, drive the copper into the depression below it. As
constant hammering hardens copper so that it ceases to respond to the
blows, it is necessary to soften up the metal by annealing as the work
goes on. Take the sheet off the block. To do this, place the point of
the chisel under the copper sheet close to the nail head and pry the
nails out, lifting both copper and nail up at the same time.
After annealing, nail the copper plate in the same place as before.
With the wooden peg continue driving until you fill the depression, at
the same time flattening all parts of the metal that may push up. Be
careful not to mar the copper at any time. When everything is perfectly
flat and smooth take it off as before.
We are now ready to draw the 5-in. circle on the copper. The centre for
this circle is the centre of the depression; and that is found with
the dividers in the same way as you found the centre for the bottom
of the bowl. Make the circle on the copper. With the shears cut along
a little on the outside of this line. Smooth up and round the edges
of the tray with a mill file. Rub out file marks with a little piece
of emery cloth. If the hammering has been uneven some parts of the
copper will have stretched more than other parts and the tray will not
lie flat when placed on a table. To level this up, place the tray top
side down upon a bench or table and strike gently with a mallet on the
surface. Holding the mallet near the head one can control the blows
and be able to strike gently. But if it is held toward the end of the
handle the blows will not be uniform. This applies to all hammers,
whether of wood or steel. You will notice as you do your hammering the
high spots will settle down and gradually flatten. The tray is now
ready for cleaning and polishing. This is done in the same way as you
treated the bowl.
_Decoration:_ Round trays may be decorated in many simple ways by
drilling holes in the rim, and then sawing out designs to suit one's
fancy, or they may be notched at intervals. Nothing is more decorative
though, than the embossed or repoussé design, made by beating from
the back and raising the metal on the face above the level. One of
the designs given here shows the embossed, and the other shows a
combination of the embossed and sawed out work.
_The value of the mould:_ It may seem to you like a lot of work to make
a mould just for this round tray, but it can be used many times for
making this kind of tray and also for trays of similar shape, like bowl
covers, etc. Most of the jewellery nowadays is made in moulds, wood,
steel, or lead. Copper, silver, and gold medals, pins, rings, tea and
dinner sets are all made by the mould or die method. This mould you
have just made is only a simple one; however, complex ones are made in
the same way. The skill all lies in making a very good design first and
then in making a very smooth mould to fit the design. After one or two
trials it comes easy enough. The chapter at the end of the book will
explain die and mould making in modern copper, silver, and goldsmith
shops.