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Photos: The original Tree Stump. At work filling the tree-trunk mould is Mr Ramon and Mde Ramon who will finish the polishing in a few weeks. Further details about the artists and La Fonderie de Bronze Lauragaise.

Casting of the bronze moulding of the eucalyptus tree trunk at the Fonderie Lauragaise at Blan (Tarn)

From P. BÉRARD, Laperouse Museum in Albi

On 13 November [2012] the spectacular operation of casting the eucalyptus tree trunk took place, a facsimile of the one that formerly stood near the tomb of Père Receveur at Botany Bay. This copy is destined for the Australian Lapérouse association. The preparation of the double-walled mould made of graphite, resistant to molten metal at 1200o, is rather complex.A first impression is taken in elastomere and is then transferred to this hard material with a vessel inside which contains a complex pipe system, to ensure a good dispersal of the bronze and the progressive elimination of air and burning gases. The mould itself is heated to 800oin an autoclave to avoid any thermal shock. This operation, which includes rapid and dangerous handling manoeuvres, is critical. In case of serious imperfections, there is nothing to do but to make another mould and a new casting, although the molten material itself costs more than 1000€.

After cooling, removal of the pipe system and the interior and exterior moulds, and repair of slight imperfections, the process remains a long job, in several stages, a little like that of leather [tanning] which changes a rough unattractive material into a product that is pleasant to look at and to touch, true to the original.

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