Making tapered wire

Greetings all, I’d like to make some tapered wire and am looking for
effecient techniques for doing so. Ultimately I’d like a piece
approx. 6mm in diam on one end to about 1mm or smaller on the other
end. the length of the piece to be about 12 inches. Any ideas? thanks jason

Jason, I regularly have need of a tapered wire and this is how I do
it: Anneal the piece first Pickle and clean Using the square end of my
rolling mill, I begin rolling a decreasingly smaller amount of the
wire through decreasingly smaller squares in the mill, so that I end
up with a piece that looks somewhat like a square radio antenna( the
type that collapses on itself). So, if my piece is 2.5mm at the large
end, I would roll 80% of that wire through the squares to reduce it
to 2mm. I then roll 80% of the newly formed 2mm section through and
reduce to perhaps 1.6mm. I continue like this until I have reduced
the small end to the desired size. The next step in this time
consuming process is to draw this wire through decreasing size holes
in the drawplate to knock off the square corners. The last thing I do
is roll file the piece in a groove in my bench pin to smooth the
taper. I must admit that I am usually working with 12 ga BS
wire…not 6mm at the butt end! I think the technique would work, but
the drawplate portion of the process might be difficult without a
good sturdy drawbench. Good Luck

Jim Malone
Diamond Point Metalsmiths

Hi Jason, I read in a book recently about tapering wire by step
rolling it on a wire rolling mill. Cast an ingot a little thicker
than your finished desired dimension and roll to the desired
thickest dimension, then step down a size and roll another section a
little smaller, step down in size again and repeat till you’ve got
the desired sizes. Finally, hand forge the wire smooth to eliminate
the visible steps. Never done it myself, and I imagine it will take
some careful consideration as you do it, but that’s the process I
read. Hope it helps, Mike

Hi Jason; The best way I know of to do this and the least wasteful of
materials is to anneal, then using a rolling mill which can roll down
square stock, step mill it down. This will require frequent
annealings and a little calculation about volume to start with the
right length. I’d suggest testing on a piece of 6 mm brass stock.
Start with a good length of 9 inches or so. Play around with milling
one end. When you finally get a taper you like, it should be easy to
determine how much you can cut off to retain the 12 inches. Subtract
that from the 9 inch measurement. That will give you an approximate
length to start with. Now you can round out the stock and even out
the steps in the taper by annealling and forging. The rounding and
evening won’t add much to the length.

David L. Huffman

the next step in this time consuming process is to draw this wire
through decreasing size holes in the drawplate to knock off the
square corners. 

One recommendation that I have at the stage of making the stepped
tapered square wire is to be sure at each of the incremental
dimensions to rotate the square wire 90 degrees and give it a pass in
the rolling mill. This rounds out the square wire into more of an
octagonal profile faster in preparation for the next more time
consuming step. Also be sure to file/scrape off any of the flashing
or little wings a that may appear if you squeeze the wire too
aggressively; make sure that they do not merely fold back on
themselves which will cause troubles further down the line. Happing
Tapering.

Mark Kaplan Providence, Rhode Island