Making my wax tree wasn’t as easy as I though it might be. It got very fiddly especially with my small pieces of the ring, with the bark texture that I was trying to cast in bronze.
First, I created a wax tree trunk which would take the initial flow of bronze, with a funnel at the top. I then created branches called runners with the pieces attached. The I created the risers which allows the air too escape when the bronze flows into the pieces. Bronze casting uses the hydraulic pressure from the weight of the bronze to force the bronze into the pieces, so the air can’t just bubble up to the the top like water, it needs a path to rise up.
Once I had finished constructing the tree. I then began to etch the tree pattern into the wax, I found this very difficult to do because I was trying to create texture when in real life the tree rings are color not texture. Another thing that I didn’t foresee was the shrinkage of the wax during casting. The outer ring of the 3D print was already a little bit too small and when I cast the wax the rings were slightly smaller again so no longer fitted into each other properly. I got a around this by layering sellotape on the edges of the rings, making sure it still curved to make them bigger so they would fit (even though they didn’t due to they curved nature of the rings, they fit with a fit of force and rotate okay in each other, in wax). I am re-casting the wax rings anyway so this shouldn’t change the aesthetic of the pieces. I have also decided that I am going to make all the rings out of pewter to achieve the unbroken perfect machined effect on one side of the medal, I think glass would not only add more very tricky casting processes, but will also break up the machined effect I’m trying to achieve.
In addition to this decision I have decided to laser etch the pattern of the tree onto some card and then stick this to the wax and then recast, as it is proving to difficult to do it by hand, as nice as it may be. I might cast one done by hand anyway just to see how it come out in pewter. After speaking to a metal technician I have decided to try and get the rings into each other without braking them, as pewter is quite a malleable and soft material it might flex just enough to fit the rings inside each other.