I had been meaning to do a full size figure in faux bronze for a long time and after the end of my work with Ripper Street, I had a few days to play around with it. Here is the result:
3D scan courtesy of Artec 3D. www.artec3d.com
After a small amount of work in 3DCoat, I capped the holes and sent it to my cnc router.
It was cut in several 80mm thick slices…
As soon as the filler, which was “lightweight spackling” was dry I began the first go of sanding. The job here was to get rid of the tell tale lines left by my 60% stepover I was using on my milling bit. The more passes you make the better the finish from the cnc but the longer it takes. There is nothing free in this world. With larger gently curved areas manual sanding seems more time effective.
Then on to a coat of BIN primer. This is an interesting product. It is a white pigmented shellac sealer. Alcohol based so foam friendly. It dries very hard and allows the hairiness of the foam to be smoothed away quite a bit. Here it is just after application, the tips of all those bits will sand right off once the primer cures…
Then more sanding and the first coat of artex filled black emulsion. This was a short cut for smoothing out the surface. It also created whats known a a disclosure coat. The high contrast allows you to very easily see the bumps and recesses.
Now the object here was not to get a perfectly smooth surface but at least to loose the cnc lines and give an acceptable cast bronze texture finish. So after a second filled black emulsion layer I moved on to the bronze metallic base layer…
This metallic base layer was a mix of burnt sienna, black and gold acrylic paints. I ran out so I left the bottom of the base black. Next layer was a very watered down 10:1 coat of acrylic gesso.(See note on gesso below) I wanted to dull down the sheen of the base coat before I went on. I sponged at on all over and let it dry.
Then on to the patina. It was done with white acrylic gesso, phthalo turquoise, and burnt sienna. I used various methods. Sponged on, stippled with a chip brush and washes running down. I tried to use the natural flow of the wash to guide my stippling and give me some idea where the worst/best patinas would form. Overall I’m pretty happy with the result. If I was to do it again I wouldn’t use the gesso. The filler in it was very heavy and tended to sit in the recesses while the other pigments washed out, leaving it overly white. Next time ordinary titanium white! I was conservative with the colours in the patina because it is very difficult to go back if it starts looking too cartoony. Its a very interesting process, working in foam on the cnc. It can be a very fast way of getting to a mass shape but finishing is still a slow and labour intensive process.
Feel free to get in touch if this process might be relevant to your project.