Recently in the studio I have been looking at ways I can offer clients a broader range of finishes for their work. One of the popular processes I use in the studio is casting metals such as bronze, brass, Iron and copper other wise known as cold casting. Cold casting is the process of suspending real metal powders within a resin binder, the surface can then be burnished back to expose the metal in the cast, making it possible to achieve many metal finishes. Using metal powders in this way achieves great results but one of the many frustrations I have found with this process is the poor range of finishes available to patinate the metal once it is cast, finding myself generally restricted to special effects waxes which I find often look plastic and do not offer the beautiful range in colours and textures that a real foundry cast patination can offer.
This fueled my search for a solution and I started to look at old chemical patina recipes that have been in use by foundries for centuries. These chemicals, unlike waxes, which are essentially just painted on, react with the surface of the metal by oxidising or corroding the metal, creating a vast range of colours and textures on the cast. Seen as cold casting uses real metal powders, I saw no reason why this should not work the same. The main difference however that I have discovered is the use of heat in conjunction with these chemicals. Cold casting does not allow you to heat the metal up to the same temperature you would be able to if it was pure metal, as the resin will just go chewy and eventually ignite! because of this there are some limitations with cold casting but some patinas work very well applied cold, the key seems to be more about the surface of the cast. A sand blasted surface will always work better as the chemicals have more surface area to key into and it also ensures that the resin has been properly cut back and the metal is exposed fully to react with the chemical.
After endless experimenting and playing around I have found some great results and am now fully convinced that cold casting is a successful, more economical alternative, where foundry cast sculpture is not always possible and am excited at the opportunities this can open up for artists and makers who want to cast their work but have limitations due to cost. It now makes it possible not only for the maker but for the every day Jo to buy and invest in art that we would otherwise not be able to do.
I am still experimenting and seeing great results, see the pictures attached on this blog and keep an eye on my instagram and Facebook page for regular updates. Remember to like my pages too!