Ancient 'Lost Wax' bronze pouring art doesn't wane in Launceston

‘Lost Wax’.

It’s a technique dating back about 5000 years, and evidence of it is hidden in plain sight, scattered around Launceston.

It’s a way of pouring and casting bronze, and it’s still used to create sculptures today.

There are only two still-pouring foundries in Tasmania, one is at the University of Tasmania and the other is at sculptor Dr David Hamilton’s house.

Most of the statues in Launceston, including some in City Park and Royal Park, were made in foundries in Melbourne, Hamilton said.

“The wax is lost away in the process and into the void where the wax was, the molten metal is poured into it.”

To create bronze sculptures required reasonable facilities with a crane to lift heavy moulds and sculptures, he said.

Hamilton taught at the University of Tasmania for 35 years as a senior lecturer in sculpture and for several years, he helped run a commercial foundry.

They weren’t small works either, one was a four-tonne sculpture which found its new home in Singapore.

He built the foundry at the university in 2005 soon before he left.

Hamilton spoke over the roar of the diesel-powered furnace as it heated up bronze ingots – blocks of metal shaped like Toblerone bars.

Heat radiated through the room, but it was still not hot enough to start pouring

To melt bronze, the ingots have to be heated to 1300 degrees, which took about half-an-hour at the Foundry at the University of Tasmania.

The ingots were warmed along the shifting doughnut-shaped ring, which hid all but the flames expelled through the hole.

As we waited for the bronze to melt, Boldkald occasionally added more ingots to the furnace, Hamilton started to talk about the history of the technique.

It was about 3000 years BC when the technique was discovered, he said.

“The original metal casting process was made to make tools, they were pouring molten metal and they found by adding tin to copper, the metal would run much easier and you’d actually make a nice object,” Hamilton said.

The copper was mined around the Mediterranean region and the tin that was used for the original bronzes came from South East Asia, he said.

“It came by trader route, right around India, up through the Red Sea to what is now Turkey or Northern Iran.”

Somewhere in history, people discovered they could create accurate and detailed forms by starting out with wax objects.

By enclosing it in a mould made of clay and horse dung, and putting it in a fire, the wax could be burnt out and pour molten metal into the crevice left behind.

“That gave you a really accurate and detailed form,” Hamilton said.

“This is the process that’s been used right through to today for casting all statue work,” Hamilton said.

“The advantage for sculpture is that you can get very fine detail.”

It meant they could get “fingerprint detail” on their work, he said.

Sculptures were also hollow, which meant reduced weight and cost compared to a solid metal figure.

“Most of the work comes after the casting,” he said.

Boldkald gave us a nod and it was about ready to start pouring.

The bronze was ready, the moulds had been prepared amongst a bed of sand and we all had our safety glasses and gear on.

It was a quick process after the furnace was turned off.

They had only a couple of minutes before the bronze solidified and they would need to start again.

The lid was shifted and using a set of large tongs fused onto a metal bar, Boldkald and Hamilton lifted the crucible out of the furnace.

Then the crucible was placed into the shank pourer – a device which allows them both to pick up the heavy container, sharing the weight and accurately pouring it into moulds.

“It’s like a giant ladle,” Hamilton said.

The crucible weighed about 40 kilograms for the three-mould pour, but it could weigh more than 60kg on a larger day.

After skimming off the impurities onto sand, Boldkald tilted the crucible and the molten metal flowed into the cast.

Hints of steam hissed out of the mould through small vents, which prevented the air from affecting the sculpture.

In less than a minute, the three pours were finished and excess bronze was poured into ingot moulds, part of a ‘waste not, want not’ approach.

But it was far from the end of the process, as Boldkald and Hamilton both need to remove excess debris, sand and prepare their works for presentation.

Boldkald created a full object when he first started using the technique, but has since adapted it.

“It’s now cheaper to use cardboard and dip it in wax,” Boldkald said.

“The wax is more expensive than the bronze.”

It wasn’t long after the bronze was poured that they started talking about smashing the moulds to pieces to see the metal figures inside.

Boldkald discovered the technique when a small bronze-making course was on offer while he was studying at the university.

“We used to make small little bronze sculptures … you’d carve out a bit of cuttlefish bone and pour a bit of bronze into it.”

The two cuttlefish bones were used as a mould, but Boldkald now used sand and cement to form his artworks.

“I saw the possibilities of that.”

Boldkald has been practicing the techniques for just shy of a decade and continued experimenting with new ideas to create his sculptures.

Letting his work and techniques stagnate was not an option.

“I like the possibilities of making bigger and better things all the time,” Boldkald said.

“Bronze (making) was one way you do the intricate little piece to start off with then you turn it into a solid piece.” 

“It’s two processes and it’s a mindset while you’re making things.”

His interest in creating sculptures from bronze started at the University of Tasmania, where he studied his undergraduate in 2007 before completing a Masters in sculpture.

Creating objects using ‘Lost Wax’, he could forge the fine details in his work while working away at any of the edges he didn’t want.

“I have to do something to know how to do it and so I keep learning,” he said.

The university is looking to run a series of workshops teaching the ancient technique, which will be open to the public and students next year.

If anyone is interested in finding out more about the workshops or the artform, register by contacting the University of Tasmania’s School of Creative Arts in Inveresk at