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Why Bronze Sculpture is so Cheap
by Kerry Cannon
I’ve been asked by my web guru Steve to explain the process of making bronze sculpture in an effort to be entertaining and informative with the end result that people will flock to buy my sculpture because they’ll know that they are receiving value for money and can explain to their collectors’ pals when they roll their eyes at the price tag, how much of a bargain they got and why. They can boast about how they happily paid too little for a piece of Kerry Cannon’s passion and how he is still smiling because he can use that money to create more bargains. I love you bastards!
None of this is easy. Bronze is one of the oldest processes known to art. Bronze pieces have been recovered virtually intact from BC shipwrecks. Ancient figurines decorate the mantels of stinking brothels in inner city Cairo. It’s an enduring sort of art that requires little maintenance or care, but the manufacture of bronze is the pits!
First you come up with the idea and create a story and break it into scenes and compositions. You can then make detailed sketches or do what I do and trust the force and go for it without any detailed drawings. You can sculpt in either clay or wax and then make a mould if you want to make more than one of your sculpture. I usually try to sculpt the base of the piece in clay, cover it with plaster, remove the clay and then, voila!, I pour melted wax into the plaster to make the copies. You fill in the holes in the waxes and smooth out the rough spots with a scouring pad and a little turps, fill your esky up with individually packed wax dolls and send the whole mess to the foundry and start on the next compositions.
At the foundry really the fun is only beginning. The workers take the waxes and get them ready to make into bronze. They connect runners on your figurines-some for the bronze to run into and some for the air in the mould to escape. If the pouring temperature of the bronze is wrong or the air obstructs the flow of the bronze then you may get “short runs” such as hands without fingers that have to be painstakingly reconstructed during finishing. The figurines with the runners are dipped into a ceramic slurry that hardens and forms a mould around the waxes. The wax is then melted out and lost hence the name “the lost wax method”. With the wax gone, the mould is now hollow, however, it is still not quite ready for the bronze. Cracks and imperfections have to be filled in and reinforced with fibreglass dipped into the ceramic slurry and then thin wire is wrapped around the mould to further strengthen it and is then dipped once again to hold it into place. The completed mould is then kiln dried to get it ready to pour bronze into. Sometimes further cracks are found after the kiln and the moulds have to be further reinforced.
There is nothing particularly scientific about lost wax casting. Moulds can crack or blow up in the process and then have to be put through again and if you’re doing a “one off” you have to go back and resculpt the whole mess again. Random events and imperfections do occur leading to some dubious results.
Once the bronze has been poured, the ceramic shell is destroyed and everything that was once wax-the figurine and runners- are now bronze. The runners have to be ground off the figurine and the original texture restored. All the remnant ceramic shell has to be sand-blasted out of the figurine. The short runs and imperfections-pin holes and larger holes – need filling in and again retexturing. The finished bronze is then put into a “rumbler” and polished before it is welded onto the base for the final composition.
The final composition is now wanting only paint or a patina. There are a whole slew of colours available in the patina. We usually use the traditional sulphur or liver patina, a ferric or iron patina, or a copper. These chemicals we use alone or in combinations and yield anything from a black opaque colour to a reddy or a green or a translucent blondey colour. The idea of the patina for me is to put it on in thin layers much like an oil painting so that the metallic sheen comes shining through.
After the patina, the final piece can be covered in wax to
seal
the patina in so that it is not affected by the elements. Bronze is a soft and highly reactive
metal. It is over 90% copper and if you
don’t seal in the patina with lacquer or wax, the atmosphere will continue to
react with the bronze and change the patina.
The wax tends to dull the final patina colour and if the piece is
destined for an inside setting you can maintain the bright patina by not
sealing it.
The thing is now
done! Now we take it to a gallery and
they take their 50% commission even though your material costs are over 100
times the material costs of a painter who is also paying a 50% commission. Is there justice in the world? I love you bastards!