Drawing fine wire

Hi Cathy,

I profess to be the resident expert on drawing fine wire… I heard
that you could draw an ounce of gold into a wire over a mile long, so
I wanted to try. I used 22 kt wire that we alloyed from Jean Starks
granulation class.

I drew it to about 50 gauge, so small that you couldn’t see it
unless the light was shining on it. I found the draw plates from
Allcraft. They start at 30 gauge and go from there. Called Filigree
wire plates. I gave about 100 feet to Jean.

She said "Why did you do this? I said, because you don’t know anyone
who has done it before… She said, “What am I supposed to do
with it?” I said, “You can’t do anything with it until you have
some.”…… I know, I’m a smart alec.

Drawing to 30 gauge was easy. The tricks which you have probably
already learned aRe:

  1. Use the tongs, but use a #6 file and file the teeth smooth. Then
    polish. Any roughness will cause the wire to break the next time.
    There are two type draw tongs, large and small. I used the small
    ones and it was easy to remove the serrations in the jaws. This is
    easier than using pliers, as the handles are bigger/longer and you
    can get a better grip on them.

  2. I use a Black paper clip, the wide kind you use to hold an essay
    together, and put a wad of cotton in it. I soak the cotton with 3
    in 1 oil, and clip it on the wire on the other side of the hole I am
    drawing through. That way, the wire continues to get lubricated as
    it goes through the draw plate.


  1. After you draw it through one hole and need to point the end for
    the next hole, use a split mandrel in your foredom tool, and put in a
    strip of about 800 sandpaper.

Place the end of the wire on your finger, and use the sandpaper to
taper the end, while turning the wire slightly. This won’t take the
skin off your hand, but you could use a glove if you have thin skin.
As you get smaller gauges, use finer sandpaper. I used about 4000
girt (pink I think) as I got down to about 40 gauge. Then I used
about 8000 grit for the remainder. After you get past 30 gauge, you
can’t really tell if you have a taper or not, just poke it in the
next hole and see if it goes through.

  1. Anneal after every other hole you draw it through. As soon as
    the wire becomes “springy”, anneal. I annealed in a kiln after about
    26 gauge. I used one of the tabletop “melon” kilns. I turned the
    kiln up to full power, and left the gold wire in there for about 15
    minutes. I annealed till the 22 kt gold got black, then pickled.

Love and God Bless

OK Randy, Did you indeed draw the gold into a wire over a mile long?
Just curious.

Judy in Kansas

Judy M. Willingham, R.S.
B.A.E. 237 Seaton Hall
Kansas State University
Manhatttan KS 66506
(785) 532-2936 FAX (785) 532-6944

Hi Judy,

I knew someone was going to ask that question, so I had already
started calculating an answer.

I measured the result of the final wire. It was .10 mm in diameter ,
which comes out to roughly 38 gauge. ( I guessed at the gauge
earlier, just knew it was much smaller than 30 gauge on my measuring
device.) A 5 inch piece was .10 mm in diameter, and weighed .1
carat. A 50 inch piece would weigh 1 carat.

An ounce of gold weighs 28.349 grams or 141.74 carats.

So, if I had drawn out the whole ounce, I would have had 50 x 141 or
7050 inches or 587 feet. A mile is 5280 feet, so I would have drawn a
tenth of a mile for a whole ounce of gold, using the smallest hole in
the drawplate I have.

The gauge size is a logrithmic regression with the equation D
(diameter) = 3.6594 * e^(-.1162x) where e = 2.7183, and x is the
next gauge number. I started at gauge 8 to get the final numbers and
generate the equation.

I plotted this out in Excel (workbook attached if anyone is
interested) and to get ten more times the length (a mile), I would
have to use a gauge of 48 , or a diameter of .0312 mm.

A human hair is of the diameter .06 mm, so it would have to be half
the thickness of a human hair to reach a mile for an ounce of gold.
The below indicates it can be drawn to 5 miles. Using my
calculations, it would be 58 gauge and that would be .01 mm and its
length would be approximately 5 miles.

I guess someone can do it, but I had great fun getting to 38 gauge.

From the Gold Institute:

  Gold is the most ductile of all metals, allowing it to be
  drawn out into tiny wires or threads without breaking. As a
  result, a single ounce of gold can be drawn into a wire five
  miles long. Gold's malleability is also unparalleled. It can be
  shaped or extended into extraordinarily thin sheets. For
  example, one ounce of gold can be hammered into a 100
  square-foot sheet. 

  Millions of computers are manufactured worldwide each year and
  gold plays an active role in their many components. The most
  important use of gold is as a fine wire that connects circuits
  to the semiconductors, or the "brains" of the computer. This
  "bonding wire" is specially refined (up to "five nines" or
  99.999-percent pure gold) and has an average diameter of one
  hundredth of a millimeter - smaller than the diameter of a
  human hair. 

Attachment Removed

Love and God Bless