Loss Compensation on an 18th Century Ebonised Table Cabinet
By Kate Aughey
Despite the age of this charming little cabinet, the losses to ripple mouldings, carved motifs and pressed foils were fairly minimal. A small section of ripple moulding missing from the front of one door distracted attention away from the otherwise pretty proportions. Although less disfiguring, two carved motifs had also been lost from the top of the drawer, which left the drawer looking unbalanced in comparison to the bottom one.
With examples of both the missing mouldings and carved motifs still in situ, it was possible to make silicone moulds directly onto the piece using Tiranti RTV Putty Silicone and T6 catalyst. This was done by first coating the surfaces to be cast in a thin layer of clear beeswax which would act as an isolation layer, protecting the original surfaces during the casting process. The silicone and catalyst were then mixed together and pressed firmly onto the moulding and carvings to ensure the maximum level of detail was captured.
Once set, the silicone moulds could be peeled off and the original surfaces cleaned of any traces of beeswax and silicone with a cotton swab and white spirit. Epoxy resin was the most obvious choice to cast the new elements due to its inherent strength and the ease with which it can be coloured. Black earth pigments were used to colour West System 105 epoxy resin before it was poured carefully into the silicone mould. Tapping the moulds sharply encouraged any air bubbles to rise to the surface, making a blemish-free cast.
The slightly uneven distribution of the earth pigments through the epoxy resulted in a surface that mimicked the patinated surface of the original mouldings and although unintentional, proved very effective. For a uniform colour, the pigments could be ground into finer particles and mixed more thoroughly or small quantities of other pigments can be combined to emphasise the mottled effect.
After curing, the casts were removed from their moulds, cut to size and cleaned up through light filing and sanding which removed any sharp edges. The casts accurately matched the original material and so did not need additional colour matching. They could then be adhered directly to the cabinet door and drawer with hot animal glue.
It is interesting to note that after several casts were made from the same mould, there is a noticeable deterioration in the detail obtained. The surface of the later casts was far less glossy and so new moulds would need to be taken if the mould was to be reused more than three times.
This relatively quick process resulted in new decorative components that blend effectively with original material while remaining distinguishable as recent replacements.
