In this blog post I am sharing with you how I created my copper clay pendants.
A few years ago I purchased three packs of ArtClay copper clay and then did nothing with the clay, because though you can torch fire this type of metal clay you really need a kiln to get good results. And up until last November I didn’t have a kiln. However I always wanted one, because years ago I attended a PMC workshop in Cornwall at the Mid Cornwall Jewellery School and really liked working with it. You can torch fire metal clays, but it depends on the size of the project and the type of clay.
Last year my dad asked me what I wanted for Christmas and I told him I wanted a kiln. And I promised him to send him photos of my work – and to write this blog post. So hopefully he’s reading this. 🙂
As space is an issue in our home I opted for the smallest kiln available which is also versatile at the same time – the Prometheus Pro1. It’s a cute little kiln which is programmable and has a timer and you can also enamel with it. You won’t be able to mass produce with it, but for a small amount of items it’s very useful.
After Christmas I finally started using the kiln. First though I had to make things to fire and do a test firing to see if the temperatures and kiln settings are correct.
ArtClay Copper is fired at a very high temperature – 970 C at full ramp.
Creating the pieces
For my two first batches of clay (2 packs of 50g) I used my beautiful texture sheets. I also made moulds from shells with a two-part moulding compound (if you want to see how I make those I recommend you watch this YouTube video I made a few years ago). For the final batch (also 50g) I chose to try the engraving technique and used some skeletal leaves to impress onto the clay. For the engraving technique I had to let the clay dry first before engraving them. I then transferred my cat drawings onto the clay with carbon paper and carefully engraved the pieces with a fine ball point tool and a scriber. This took a very long time as I had to go over the areas several times to make it deep enough. When I made mistakes I was able to use a fine file to “erase” those mistakes. I had to be careful not to go too deep or put too much pressure on the clay as it could easily break in the dried stage.
Working with this type of clay is very different from my usual medium polymer clay. With polymer clay you can take your time and don’t have to work against the clock. You can leave a project covered up with kitchen foil (so it won’t gather too much dust) and keep it away from any heat sources and get back to it at a later stage. With metal clay you can’t really do that as it dries relatively quickly and to avoid that you have to keep a bottle of water handy to moisten it again.
You can however add clay to dried clay and use clay paste. I haven’t done this with the copper clay though. Also while I often wear gloves when I work with polymer clay, with the metal clay you need to cover your hands with Badger balm or olive oil so your hands don’t dry out the clay. And you need to cover the surface area with olive oil or Cool Slip so it won’t stick to it, but be careful not to use too much of it! The good news is that you can reconstitute dried clay and make a paste from it.
Another thing that can be an issue with copper clay is that when it’s exposed too long to the air it can start to turn black (oxidize) which is definitely not what you want. I noticed this with a tiny rest I had leftover – even wrapping it in kitchen foil didn’t stop this from happening.
Next step was to let the pieces dry (apart from the engraved ones which I engraved in the dried stage). It’s very important that they are absolutely dry. You can use heat plates to speed up the process, but I don’t have a heat plate and just left them to dry on my table for a few days.
Once they were all dried I filed them with a very fine 4-sided file to make sure the sides are nice and even. I also carefully drilled holes into my shells. My other pendants all had holes inserted at the wet stage.
Firing and pickling
After filing it was time to test the kiln first with a test piece. I noticed that my kiln does fluctuate a bit – up to 10 C, but thankfully it doesn’t matter too much. I had to learn how to actually program the kiln. For copper clay I programmed it to ramp it up at full speed to 970 C and hold it for 30 minutes. It takes about 45-50 minutes for the kiln to reach this temperature – and the only downside is really that I have to keep an eye on the time and temperature so I know when to actually put my items into the kiln. The kiln has four small kiln posts on which I put the fibre kiln shelf – as you can’t put anything on the floor of the kiln. You also have to mindful that you don’t obstruct the temperature probe at the back of the kiln.
I put the first batch for firing on a prepared shelf that had some special shelf paper on it. I read that ArtClay copper clay tends to stick to the shelf and I wanted to avoid that. Copper oxidises quickly and when you fire it in the kiln the pieces can come out with fire stain on them. So when I took this first batch out I put the pieces straight into cold water to quench them. However that’s often not sufficient enough to clean the pieces off, so they went into the pickling solution. For this I use a small slow cooker dedicated just for this purpose (no, we don’t cook food in this!). This first batch took a while to clean up. So for the next batches I used bits of fibre blanket to cover the pieces with. Once quenched in the water the fire stain came off with the fibre blanket. I tend to leave the items in the pickle for at least 30 minutes or longer, depending on how they look. Once pickled I brushed them with a steel brush – this is where the magic happens and they change into proper bright copper coloured pendants.
I don’t like polishing much due to my shoulder problems – polishing aggravates it and is very painful. Against my better judgement I polished the first few pieces with special polishing papers. I found samples of them I received at last year’s Polymania event. You have to go through each grit when polishing. This is not only time consuming and rather boring, but also in my case very painful. In one of the Facebook groups, I am member of, I was recommended to use a tumbler. So I decided to finally make use of my polishing tumbler which I had for ages (also a gift from my dad). To use this machine you need to put the steel shot into the barrel first, then the jewellery items and then enough water to just about cover them (not too much as the tumbler has a weight restriction). I also had to add some polishing liquid- two drops, which was tricky as the bottle just has one big opening. So I ended up using a syringe to get out the amount needed.
I polished the pieces for about one hour or slightly longer. As all pieces had a lovely texture I didn’t want to polish them too long and polish away the raised bits!
The pieces all turned out bright and shiny.
Adding the patina
Copper oxidizes quicker than silver, which can look nice. However,you can also achieve an antiqued look by using a few drops of liver of sulphur. The stuff stinks of rotten eggs, so I did this in the conservatory with the windows open. I hung all items on wire so I could easily dunk them in the solution. The solution is made up of a few drops of sulphur which are added to warm water. You can dunk it for a few seconds or longer. The longer it’s in the the solution, the darker the metal looks. After dunking it in the solution I left it in cold water with a spoon full of bicarbonate of soda to clean them. After drying the pieces I gave them a final polish with a polishing cloth.
Copper can react with the skin and turn it green, which is why I had to find a solution to prevent this issue ( you don’t want to look like the incredible Hulk!). I found advice in a FB group and bought Midas Lacquer from Kernowcraft. The final step was giving both sides of each pendant several layers of varnish. And then it was time to assemble the chains and add the finished pendants.
You can watch the whole process in this video:
I hope you like the results and found this blog post interesting.
You can find my copper clay pendants in the shop.
Thank you for reading. 🙂