Cold Casting

While I was on holiday in Bali in 1987, I saw a lot of stone statues, which I would have liked to transport to my garden back at home in England. They were not expensive to buy, but the cost of shipping them was outrageous. I decided that it might be a good idea to make moulds of them, and then take the moulds home and cast them there. At the time I had no latex with me and anyway I figured probably I would need some practice in order to not end up leaving latex coated statues behind me, when I left Indonesia.

When I did get home, my first step was to buy a ready made latex mould of a Buddha, from which I cast about a dozen concrete Buddha's to ornament my garden. I then purchased some liquid latex and made my own mould of a wooden head, which I had brought back with me from Bali. Unfortunately, the mould would distort somewhat with the weight of the concrete, so the heads I cast looked like they had been born somewhat disfigured. I then purchased a plaster head from a car boot sale and used that as the basis for another mould, but this time I reinforced the latex, by building a three piece outer shell from fibreglass. This worked much better.

To this day I have still not returned to Bali with a big pot of liquid latex. It was then probably two decades since my first attempts, before I decided to try casting again. On this occasion I was motivated by a desire to replicate a small clay bust that I had commissioned a sculptor to make, of the French King Henri IV. I was worried that the cleaning lady might knock him down with her feather duster, leaving him shattered on the floor, so I decided to create many more Henri's.

Even though this bust of Henri IV was quite small (6" or 15cm high), I decided to reinforce the latex Mould as a precaution against distortion.

First I rubbed some washing up liquid detergent into the paint brush bristles, to prevent the latex adhering to them. Then I brushed the latex over him.

I ended up applying about 15 coats of latex. The first job after applying each layer was to quickly wash the brush in cold water, and the next job before applying the next layer was to coat the bristles again in liquid detergent. I allowed at least 3 to 4 hours for the latex to dry, before applying the next layer.

Once the mould was thick enough, I constructed the support shell from a material called Sculptamold. The only reason I used this was because it was all I could find in my local hobby shop that seemed to be suitable for the purpose. It is rather like a slow drying plaster of Paris. In fact it was very slow, taking over a week to set fully hard. I had a job finding a suitably container of the right size, so I ended up rigging up the rather Heath Robinson effort in the picture above. The plastic tub was partitioned off with another piece of plastic so I wouldn't waste too much of the Sculptamold material. Because it was a bit large and I didn't want to cut it, it ended up sloping and curved.

I then used a couple of plasticine pillars to prop up the latex coated head (NOTE: that I did not remove the head from the latex, since the latex could have distorted while making it's supporting shell). I then filled up the void with Sculptamold, which I had mixed with the recommended amount of water. I filled it up until the head was half submerged. Once it was dry enough, I made an impervious barrier of tin foil. I could have used another material such as cling film or polythene, but tin foil was to hand at the time. I then covered the remainder of the head Sculptamold mix and waited for it to dry.

Once the outer casing was fully dry, I separated the halves (note the pink plasticine supports, which are now embedded in the casing), and removed the original clay bust from the latex. (I had first covered the outside of the latex Mould with Talcum powder to stop the latex from sticking to itself).

Next I mixed a ceramic moulding compound with the specified amount of water. I sprayed the inside of mould with release agent (I am not sure that this is necessary, but I did it anyway). I poured the mix into the mould and then vibrated it to remove air bubbles. You can't tell from the pictures, but the mould is resting of top a a budget microwave oven (the microwave is not plugged in, but the top is made of a not very rigid sheet of steel, so if you push it down it will spring back when released). By repeatedly firmly tapping the top of the microwave, I was able to create plenty of vibration. Due to the Heath Robinson nature of the container I used to make the support shell, I needed to use a piece of wood to keep the entrance of the mould level. After one hour I was able to remove my new casting of Henri IV from the mould and start another one. The particular casting compound I have been using generates quite a lot of heat, and Henri is pretty hot when he first emerges. He usually continues to sweat water, especially from the base for several hours after being cast.

As you can see from the picture above, my collection of Henri's in both white ceramic and terracotta colour is growing.