THE MAKING OF.....
THE BEGINNING OF THE ONES
Around 2018 Hoogendijk felt an urge to move away from the flatness of photography. The layers that she introduced into her photographs by manipulating the image was no longer enough for her. “I wanted to feel more, make something more tangible. I can only do that in spatial work.” Her sculptures are not however entirely isolated from her photographs. In fact, they come from them. Her The Nudes series of 2018 incorporates the abstract human figures that emerged later in The Ones. The transition from 2D to 3D was therefore a completely logical step for Hoogendijk. But it was not until she was alone in Hoogeloon, during the Covid lockdown of 2020, that she had the time, space and peace to really get to grips with sculpting.
Hoogendijk wanted to make her delicate designs more robust, so she had them cast in bronze. Working with the Kemner bronze foundry in Cuijk, she made a series of twelve bronze sculptures. She watched in the workshop as her carefully crafted designs were roughly chopped into pieces in order to create a mould. “This is happening to your most intimate work, your figures, the little people you’ve made, with feeling.” To Hoogendijk it was as if she had surrendered her creations to an inferno of violence and brutality. The sculptures were cast in red-hot bronze, but though she felt that they had lost all their brittleness, there had in fact been a transformation. “Suddenly they had become so strong. Once they had cooled they stood there, like sturdy pillars in their collective intransigence.” There is a certain vulnerability in the way the figures in The Ones embrace and support each other, but the monumental quality of the bronze makes them strong. Hoogendijk spent hours working on them, creating the right patina. “I love grinding away at the sculptures at the foundry, with no one and nothing to disturb me. At those moments I’m not thinking about anything else, and I’m as one with my work.”
CIRE PERDUE METHOD
The Making of… The Ones
Hoogendijk uses the lost wax method, also known as cire perdue, to make her bronze sculptures The Ones in their original format. This technique allows metal objects to be cast in the desired shape, resulting in this instance in a solid bronze sculpture.
Making a silicon mould
First, Hoogendijk creates her sculpture in plasticine over a metal structure. A silicon mould is then made at the Kemner bronze foundry. The sculptures are divided into pieces, and a layer of liquid silicon some 3-4 mm thick is brushed over the individual sections. This silicon layer needs to be left to set. Once this has happened, a support cap is made of acrylic one, a material specially developed for moulds. The cap enables the silicon to hold its shape.
Pouring wax
Now it is time to pour the wax. Kemner removes the original plasticine model from the mould and cleans the silicon. Then liquid wax is poured in, and allowed to cool. Once the wax has cooled sufficiently, the silicon mould is opened and the model checked. Any visible seams are removed, and the holes filled with wax. This results in a precise wax copy of Hoogendijk’s plasticine sculpture.
Making a plaster mould
Kemner then sets about creating a plaster mould. Pouring ducts are made in the wax model so that the bronze can be poured into the plaster mould during the casting process. Once these have been made, a first layer of plaster is carefully applied to the wax model. The model is placed in a wooden casing, which is then filled with plaster.
Firing
The casing can be removed after an hour and the mould is placed in a kiln. It is fired first at 150 degrees, and then the temperature is steadily increased to 600 degrees. After 48 hours of firing and a further 48 hours of cooling back to approximately 150-200 degrees, the casting moulds can be removed from the kiln.
Bronze casting
In the meantime, the bronze is melted and the casting moulds are clamped using steel plates and screw clamps to absorb the pressure of the bronze. Once the bronze is molten and at the correct temperature (1200 degrees), the crucible is hoisted up and the liquid bronze is poured through the ducts into the mould.
Removing the casting moulds and polishing
After a day’s cooling, it is time to remove the plaster casting moulds from the bronze using hammers and chisels. Any plaster remaining on the bronze is removed using a high-pressure cleaner. The ducts previously made in the wax are also removed from the sculpture. Hoogendijk grinds the underlying surface back to its original structure, giving it the same soft feel as the plasticine sculpture.
Finishing
The finishing differs from one piece to another. Hoogendijk prefers to apply two layers of dark brown wax after the grinding process is complete. The sculpture needs to be heated and the wax applied by brush. She repeats this process twice. Once it has cooled the sculpture is polished with a cloth. An alternative finish involves using copper nitrate or iron chloride to apply a colour to the surface of the sculpture. Hoogendijk always finishes her sculptures herself, by hand. This is a time-consuming process that allows her to obtain precisely the result she has in mind.
SANDCAST METHOD
The Making of… The Ones – XXL
Making a version of The Ones several meters high is a very complex process that takes both creativity and technical skill.
Digital version
The process starts with a digital version of the sculpture, made on a computer. 3D designer Patrick Beverloo scans in every little detail of the sculpture and special software divides this digital version into a number of sections.
Polystyrene version
Using the computer images, a milling machine cuts out the individual parts of the sculpture in polystyrene. These parts are assembled to give a first impression of the sculpture at its actual size.
Structure
The polystyrene version is smooth, as the computer has not recorded all the details, so Hoogendijk and Beverloo then apply a surface structure to the polystyrene using plaster. The sculpture is then given two layers of paint, a dark brown layer and then a bronze layer, to check whether there is enough relief on the surface.
Making a sand mould
The next step is to make a casting mould in sand at the Kemner bronze foundry. Beverloo and Kemner divide the polystyrene version into pieces that can be cast in sand. The individual parts are then laid in special sand to create an impression. The sand is machine-mixed with an activator and resin so that it sets.
Two halves
Each part of the sculpture is semi-submerged in the casting sand. It is then covered with a layer of loose sand. A casing made of wood reinforced with steel keeps the whole thing together. A lifting ring on the casing ensures that the moulds can be moved by crane once the pieces have set. The moulds are left to set for a day, and are then turned onto their other side so that the procedure can be repeated for the other half. The next day Hoogendijk and Kemner take the sand moulds apart and remove the polystyrene pieces from the sand. The sand mould of the sculpture is now ready. The bronze caster first applies a coating to protect the sand mould, and then applies a thin layer of wax, some 6 mm thick, inside the mould; this will be the thickness of the sculpture. He places the two parts of the mould together again, clamps them and fills the mould with foundry sand. This is the core, which ensures that the finished statue is hollow. After being left to harden, the mould is opened again and the foundry sand and wax are removed. Kemner makes pouring ducts in the mould using the milling machine, and applies another layer of coating. The sand moulds are aligned correctly and held together using screw clamps and/or steel bars. This process is repeated for each piece of the sculpture.
Casting in a sand mould
The bronze caster melts the bronze at 1200 degrees, and pours it from the crucible into the sand mould. After the bronze has cooled, the mould is opened, and the result of the process is immediately visible. Any remaining sand is removed using a high-pressure cleaner, and the pouring ducts are removed using a grinder. The bronze caster loosely welds the individually cast pieces together so that their position can be adjusted if necessary. Hoogendijk uses the digital file as a reference, as it shows the correct position of the sculpture, as well as the original small version. Once the pieces are in the correct position, the statue is firmly welded together. Grinders and sanders are used to ensure the welds cannot be seen. Hoogendijk is closely involved in this process, and ultimately decides on the finish of the sculpture, which determines it’s feel.
Patination
After a final check, the sculpture is given a layer of patina or dark brown wax. The surface is heated using a blowtorch, and the patina is applied using a brush. The process of applying heat and then patina continues until the desired effect is achieved. A layer of wax is applied using the same process. Finally, Hoogendijk polishes the sculpture.
Installation
Spikes are attached to the bottom of a sculpture this size, to anchor it in its foundations once it has been lifted into position.
