Date Uploaded: February 10, 2004, 8:12 pm
Last Edited: January 12, 2013, 2:36 pm
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Making Gold Wire
Article © MAIL User: MeTri
This was my first attempt at making my own wire from scratch. It worked better than I could have imagined.
- Small Propane/Oxygen torch
- Mold for round sticks
- Rolling Mill
- Drawing plate / drawing tongs
- Bucket of water
- Crucible / melting bowl
I have been making my own rings for some time now, but have never been able to make the wire.
To start, I heated about an ounce of 10kt gold until it was glowing yellow. I kept heat on the gold until it was in the mold. Basically the mold is cold and you have to heat the gold as much as possible so it flows into the mold and does not harden on top. This took a few tries, but the best thing about gold it you can keep melting it over and over.
So this left me with a little stick of gold, about a 5mm round bar.
My rolling mill has grooves for making square wire.
When gold becomes hard from working you must anneal it. That is, heat it up to make it less brittle. Heat the gold until it turns red -- not glowing orange, but the first red that emits light. I find it much easier to do in the dark. Let the gold cool until it's not emitting light and then quench it in water. If you quench it while red or let it cool slowly, you will be tempering the gold and not annealing it.
I have been annealing the wire every time it finishes 2 grooves in the rolling mill (about 1 mm wire diameter change per groove).
I would recommend a rolling mill that makes round wire, and not square. Changing square into round without a machine is more work than fun ;) When I have 2mm square wire, I move to the drawing plate. In case you haven't seen one, it's just a piece of hardened steel with a series of holes in it. As you draw the wire, it lengthens, polishes and hardens. Every 3 holes I anneal the wire. I stopped drawing when I had reached 1.110 mm.
When drawing wire, sometimes it's very hard to pull the wire. I basically throw all my weight into it, and it seems to work well.
At this stage I just coiled the wire, cut the coils and made a bracelet as I would have out of any other material. I found the gold very, very stiff to work with as rings. I could have annealed them, but would have then had to polish away all the fire scale.
A few notes about the above text. I am learning as I go, and have no formal training, as is the case with many of us. So I had made a few errors in the above text and would like to correct those.
Firstly buy a good rolling mill. You will spend hours and hours with this thing, make sure the movement is smooth and that the rollers don't move when you insert your work into it. I have a PEPE mill. This is a modestly priced mill made somewhere in Europe. Grobet is a good company and many Italian mills seem to be of top quality. Karat Mills seem to jam frequently and not be work any amount of money. They seem attractive at $200USD but the movement is not very good. These are my opinions from having used the above mills, and so far my PEPE is working great.
To the best of my knowledge there are no rolling mills that make round wire. Half round for sure, but not round. I could be wrong, but I haven't been able to find one. I was having trouble turning square wire into round wire with a drawing plate. My problem was with my drawing plate. I had a plain tool steel plate. I bought a new one made with Tungsten-Carbide. All holes are labeled and differ by .1 mm. I can now draw wire without aid of another person and have had almost no injuries since it's purchase. I would recommend a good drawing plate if one is looking to make wire. I paid $20 for my first draw plat and $140 for the second and I think it worth every penny.
Be carelful when handling wire, imperfections in the casting of the original ingot can pop or spring out at any time. If you start with a small round bar that you have cast, I recommend filing the edges where the two halves of the mold meet. If you don't these will get folded into the square wire as it's rolled and creat huge long splinters to appear in the final wire.
I have been mostly working in silver lately, and have found it much cheaper to buy fine silver from a coin dealer and alloy it myself. This is simply stirring in 7.5% copper before casting. I stir with a carbon rod.
If you would like to work indoors, I recommend a propane oxygen torch. The setup is fairly pricey as you have to buy regulators, but the torch itself was very reasonably priced. Using a benzomatic torch is ok to learn but at $9 / 40g of oxygen, it quickly becomes very expensive. Also when you run out of oxygen in the middle of a cast, you have wasted your time as you can't change bottle very quickly and the metal cools etc....
I am using the same mold as originally and have no problems with it. I would like one that holds more than 18g of silver as it's convenient to melt 62.2-62.4(2 troy ounces) g of silver with 4.7g of copper and with a small mold it's a bit rough to use with that amount of molten silver.
Annealing wire can be fairly time consuming. Also if one anneals the wire after it's completely done drawing, it is almost too soft to use. I anneal my 1.1 mm wire for it's final time at 1.6mm. This seems to give nicely work-hardened wire that works well for all patterns I have tried. To anneal the silver heat until it barely glows red and then allow to cool. If it get's to be a bright orange, it's hardening the metal not softening it.
Good luck to any who try to make there own wire. Hope these tips help.
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