You can make a rectangular wire die to your own size and/or shape.
Take two pieces of 3/8inch thick flat steel about an inch by three
quarters and file two edges dead square so they meet perfectly.
Clamp the pieces edge to edge and using a drill which is the tapping
diameter for the size of the small bolt you will use to bolt the
pieces together, edge to edge.
Drill a hole right through both pieces. Take them apart, and
enlarge the hole in one piece to the exact size to clear the bolt.
Tap a thread right through the second piece. Now bolt the two
together with a single bolt and hold in a vice.
Drill a tapping hole through both pieces opposite the previous edge
hole, separate the pieces and drill the clearance hole, and tap a
thread in the hole in the other piece. Bolt the pieces together.
Mark out the profile of the required wire on each piece accurately
on both sides of each piece, and carefully file a slot the size and
thickness of the required wire in the edge of one of the pieces and
round the edge of the slots of both pieces to make wire insertion
easier;; (note the trumpet profile of the holes in an ordinary wire
drawing die, and imitate this on the flat slot you have filed..
Don't file the slot in the other piece of the die, but curve the
entrance like the first piece. Now curve the slot edge in the back
of both pieces to make a small emergent curve for the wire to be
drawn. Clean up the slot with 200 grit paper. followed by finer
paper until the slot has a polish. When drawing a wire treat this
die exactly as though it were a normal single piece die.
Note that you may change the distance between the two parts of the
die so as to reduce the flat wire gently. Use wax on the wire as a
lubricant, and anneal frequently.
Sounds complicated and difficult? It isn't difficult at all. Just
think about what I have said, and if you like, make a sketch of
each step to help visualise it. It works; I have made and used such
dies myself. Note that you can make dies for wedge shaped wire or
anything you like. Even using ordinary mild steel the die will
last for quite a number of drawings. To make it last longer use a
surface hardening technique, using Kasenit case-hardening powder or
similar. (Ask about this later if you really need it.)
Cheers for now,
JohnB of Mapua, Nelson NZ