Introduction to wax carving and lost wax casting
Practiced by artisans for thousands of years, lost wax casting is an ancient technique used to produce one-of-a-kind metal sculptures. You can actually find a small exhibit about it at the Royal Ontario Museum:
The Koi Fish ring is one of my first and favourite designs made using this method. It is essentially a tiny piece of sculpture, handcarved from jeweller's wax and cast in precious metal. Below, you can see my wax model before casting (on the left), and the finished gold ring beside it.
Wax carving tools
Wax carving tools are essentially anything sharp that can be used to cut and shape jeweller's wax (many of the tools are the same as those used in woodworking, printmaking, and dentistry!)
My favourite tools are a tiny flat chisel, a craft knife, and a micromotor (rotary tool) which works with different types of burrs or drill bits. I use a green jeweller's wax, which feels a bit like candle wax, but firmer and specially formulated to hold more detail. For this project in particular, I'm using a green wax tube that already has a nice cut-out for making rings.
Jewellery design
I have always loved the movement of koi fish, especially the butterfly koi (which have ever-growing fins), and knew I wanted to try designing a piece of jewellery around their elegant, fluid lines. For this ring, I made quick line sketches until I found a shape that I liked:
Wax carving process
Working with a chunk of the green wax tube, I use the rotary tool to burr out the rough lines from my sketch. At this point, it looks more like napa cabbage than a fish... 🥬
I carve the fish's fins separately and attempt to attach them to the main body with molten wax, but unfortunately break the the ring band in the process. This often happens when I start adding detail to the wax model — it becomes more and more fragile to work with.
Despite the missing ring band, I successfully attach the fins and continue to clean up the body details and smooth out the surface of the wax. Refining the wax surface eliminates any dents and scratches from being included in the final model, and also reduces the chance of porosity (little air bubbles, or holes) that can appear during casting.
I carve a new ring band and reattach it to the main body with molten wax (for this, I use a soldering iron or a battery-operated heat pen). To create a natural fit to the finger, I adjust the position of the fins and ring band by melting and re-positioning them as needed.
Casting the wax model
I take the wax model to my local caster, where they put the wax model in some plaster. Once hardened, molten gold is poured into the plaster, replacing the wax model inside. The whole thing is cooled, broken apart, and the gold casting is retrieved.
I don't have photos of this part as it happens in my caster's workshop, so I drew a quick diagram for you instead :)
Polishing gold jewellery
To finish the gold casting, I use my rotary tool to apply different levels of polishing compound, creating lustre and sparkle through increasingly fine micro-scratches on the metal surface. For the Koi Fish in particular, I also add a special diamond-cut texture to really bring out the flourish and movement of the fins.
My favourite detail is the way the lines flow through to the inside of the ring:
More about lost wax jewellery
The lost wax process is a useful technique for making unusual shapes that aren't possible with traditional goldsmithing. I especially enjoy trying to make things that have a lively sense of movement and emotion :)
If you're interested in learning more about lost wax jewellery:
Thanks for reading!