Melting Copper with Coal (Sucessfully)

Yesterday me and my parents casted my first test cast in bronze. I was a bit skeptical whether I would be able to melt copper using coal instead of gas. The main experiment was not to cast a good artwork, but rather to determine whether if my setup would be able to melt copper. I was absolutely amazed how quickly the 500g copper melted (less then 30min). I've added 12% tin but my final metal still have a pink/ red colour instead of the yellow that I wanted. I surely have some research left in terms of mixing the perfect bronze. 

Lost foam, copper, sculpting, bronze, copper
The basic design that I've put together for testing the copper-melt. The final colour turned out a bit  pink.

The coal worked very well. We only used a little bit of coal. The whole process felt completely safe and the coal didn't make a lot of smoke. My mother made sure that there is photos that I can use to show the process as well as the setup.

Furnace, refractory blanket, melting, copper, coal, sucessfully
The coal was given more oxygen using a fan, making the coal extremely hot.The furnace is made from a double layer of refractory blanket also know as a ceramic blanket. The lid that I've placed on the furnace surely made the copper melt faster.

Furnace, crucible, copper, melting, tong, coal
The tong that I've build worked perfectly to remove the crucible from the very hot furnace.

Molten, copper, warm, hot, crucible,
Adding coal in the crucible before you start the fire and even while feeding the furnace will help removing oxygen bubbles in the copper.
Molten copper, pour, hot, bronze, sculpting
In this photograph you can some steel wire inside the crucible. This melted from the furnace lid and is a improvement that needs to be made on the furnace design.

Bronze, test casting, art,
Cooling the copper right after it has been casted will make it even stronger.

For my next cast I plan on casting a simple artwork in the "lost wax" process instead of the "lost foam" process that we've done here.


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