[[moderator's note: This posting was delayed due to moderator error. Was sent
Saturday the 16th]]

lemel_man wrote:
ted frater wrote:

...snip...
This one is something I can help you with.
Putting it simply, a rolling mill makes metal thinner IN the direction
of the rolling.
IE your 1.2mm wire will go down to the thinness you want BUT wont get
any wider!!.( ok I know there will be someone who will say it actually
does get wider by about 2/4 %)


I am surprised that this myth continues to be preached. Its simply not
true. I found that out when I wanted a 100mm 0.25mm x 1mm strip. I took
a 25mm length of 1mm square wire and rolled it down to 0.25mm. That
should do it, right? Wrong. I got a 50mm strip 2mm wide. That's when I
did the experiments. I did lots, plotted the results on a graph, applied
some curve fitting algorithms and came up with a pretty nasty equation.
I simplified it a bit and wrote a program that I've been using for a
number of years. Its not 100% accurate, but close enough to be extremely
useful. It also varies a little with the metal being rolled. I feed in
the width and thickness of the strip I need and it tells me the size of
the square or round wire I need.
For example, suppose I want a 3 by 0.2 strip 400mm long. It tells me I
need to start with 161.25mm of 1.22mm square wire, or 162.81mm of 1.37
diam round wire, and it will weigh 2.688gm in 9ct yellow gold.

You don't believe me? try it yourself. You must start with well annealed
wire and roll it aggressively, ie. minimise the number of passes and
anneal frequently. In the example I would set the roll to give 0.2mm
thickness in one pass, measure the result, adjust for the error (its
never too thin), and do the correction pass.
I can't believe I've got the only magic rolling mill in the world.


If you roll say 2in wide by 1/8in thick it doesnt get wider. it gets
longer. I would cast silver 4in long by 2in wide by 1/4in thick and
tuern that into 1/16in thick strip. Never got wider.
yuor probably right with the sizes your talking about. I never had
the need to work round/square wire to flat strip. I always used wide
stock to start with.
Be that as it may,
I woke up in the middle of the night last night and eureka!!. theres a
co that makes just the sheet our friend is looking for.
Many years ago back in 1970 i was doing lots of enamelling and used
paillions as inlay in the enamel in gold and silver. Stll have plenty
left. Aught to use them up.
Bought these from Bayeler&Co.sa. in Geneva. Now Ive just had a look on
the net and there no reference anywhere for them perhaps someone else
might be more lucky.
they made gold sheet in the thickness you need and would make up the
discs you want as well IF there still in business.
My last contact was in 1978 some 28 yrs ago. dug out their file and
catalogue. nice to look back. anyway ill find out on Monday if there
still in business.
What do you want the discs for?
just curious.
Ted