Many people are under the impression that soldering gold filled wire is either very
difficult or impossible. With just a few tips you will find that that is simply not true!
First of all what exactly is gold filled wire? Basically it is a layer of solid gold at least 10K (.417% pure gold), 12K (50% pure gold) gold or 14K (.585% pure gold) that has been mechanically bonded with heat and pressure to a thicker piece of base metal, most commonly a brass alloy that is 90% copper and 10% Brass. The gold layer is fused to the base metal, resulting in a product that has all the beauty of its actual karat gold plus long lasting resistance to wear.
It is the base metal that can cause you some problems when you are trying to solder. If the gold filled wire is over heated the brass can come to the surface and cause that copper color that is so annoying.
So to make it easy, here are some tips for soldering gold-filled wire that works for me. I make a flux of boric acid and denatured alcohol that I mix and keep in a sealed jar. I dip the whole piece in that, remove with tongs and let it dry before I heat it. As it dries a powdery looking coating forms over the gold-filled piece. Paint the areas to be joined once again with flux and a paintbrush, applying a thin coat to each piece.
USE GOLD SOLDER – not silver solder! I use either 14K extra easy solder or 10 K easy solder. Make sure you know how to pick solder so that you control the amount of solder and where you are going to put and place it on the seam.
Remember for gold filled, you don’t want to heat the whole piece like you do for silver.
You want to just heat the local area that you are soldering. Get the torch on and off quickly – do not let it sit there – don’t overheat it! For gold-filled, you don’t want to overheat because this causes the brass inside to come to the surface and create the copper color that often happens when gold-filled is overheated. You want to use a fairly low flame (but not so low that it takes a long time to get it up to temp) and heat until the solder flows and then pickle your piece as usual. I often solder one side, then flip it over and apply more solder. For some reason with the gold filled metal, the solder doesn’t want to pull through completely like silver does.
I practiced on jump rings until I got it down right! I have lots of jump rings,lol.
When you are finished, you can file or sand if you need to, but not too much, as you don’t want to go through the gold layer to the brass. Polish as usual. Buffing with red rouge will get rid of any residual oxidation.
Oh No! The torch was held in one place a little too long and now your beautiful seam is a pinky, coppery color! What to do?? There are several simple ways to get rid of the raised copper on Gold filled wire and sheet. Super pickle works the fastest (but you still have to sand and polish), half pickle- half hydrogen peroxide, HOT- you can watch the mix turn blue as the copper dissolves into the solution. It must be hot! It only lasts a short while- like 10 min or so because the peroxide just turns to water, but then you can then dump it right back into your pickle pot!