I’ve been working exclusively with silver, but have recently just made some pieces with patterned copper.
To enhance the patterns in silver I treat the silver with LOS (or black max) and wipe the patina off the surface using Pro Polish pads. That works very well and the pads easily remove the silver from the surface, leaving the patina in the crevasses.
I tried this technique with LOS and the copper pieces but the pro polish pads will not easily wipe the patina off. Is there another polishing technique that might work or some other way to adjust my technique for copper?
The Pro Polish cloths should work the same with copper as they do with sterling silver.
Remember that with liver of sulphur you are building up an oxide coat on your metal. Copper is much more reactive to sulphur than sterling silver. It’s very easy to build up too thick of an oxide coating, which will be harder to remove.
My advice is to dilute the liver of sulphur solution when using copper and do multiple dips to get the lightest coat necessary for your desired level of darkness. The Pro Polish cloth should do just as good of job on copper as silver.
In answer to your question about other ways to remove excess patina, I don’t know if you have a flex shaft or buffing machine? A cotton buff with rouge (no abrasive compounds) will remove excess patina. The advantage of that technique is that it’s fast, but it often take away more oxidation than you want.
The Pro Polish clothes are what I use the most too! Or sometime I use Sunshine Cloths if that’s what’s around. Rio Grande does sell Sunshine Cloths in different levels of abrasiveness. I’ve only ever used the yellow ones. I haven’t tried the others.
Another idea is to use a wooden backing with your polishing cloth. Way back in the 1970’s when I first started, hard felt hand buffing sticks were common. They were great for what you’re trying to do. I don’t know if they’re still around? I haven’t seen those in years. You can make something close to a felt buff stick by wrapping a Sunshine Cloth around a paint stick or similar and rub back and forth to remove excess patina. The advantage of that technique is that the hard backing helps to keep the Sunshine Cloth from going into the low spots.
I’m quite new to patina and am using Jax rather than LOS, but I imagine it’s similar. I’m using texture plates (also a new thing for me), and rather than a cloth I’m using a fine diamond file. I also do some colouring with the torch & finish it the same way.
I was looking at some videos on PotterUSA and saw Kevin highlight a texture in a copper piece using a black Sharpie. I’m not sure how that stands up to the test of time, but it very nicely solved my issue :).
I use pumice powder and rub with my fingers (yes, not good for keeping your hands nice!). I wet my fingers, dip them in the powder and rub the surface. I like the softer finish it gives the copper and it brings out a bit more of the red. It takes off more of the patina because of the grit. But it is very fine. I think it’s even finer if used dry.
Then I use a soapy brass brush if I want it shinier.