Conservation of the West Dean bell pull

By Sophie Harris

This is the bell pull from the front of West Dean House; it had deteriorated badly and was need of restoration. There were signs that it had been restored in the past; however, there was no documentation to prove this. I could see the wings of the dragon were a later addition to the piece as the corrosion pattern was completely different to the corrosion behavior on the rest of the object.

There were also signs that active corrosion was still on the piece when it was last repainted. This is shown by how the corrosion products had built up under the paint layer and pushed the paint from behind, causing it to delaminate.

The removal of paint was also exposing how the decorative leaves were being held together by paint. The dragon, the pull and the decorative leaves were most affected by corrosion. In these areas the metal is the most changed from its natural state, and so in unstable conditions it reverts back to that elemental state fastest.

The removal of the paint started off with flame cleaning; this doesn't damage the original surface, so it was the best solution. Once the majority of the paint and oxide was removed the main frame seemed to be in excellent condition and a fine piece of craftsmanship. Small areas had to be lightly air abraded for gap filling. The best way to visibly mend a gap in ironwork is with braze; however, the leaves were far too thin and this would have damaged the piece. I decided to use Milliput Ô, which is an epoxy putty; it is also a visible removable mend and will inhibit corrosion.

Two missing bud-shaped decorative nuts were replaced; they were turned on a lathe and dressed to match the original nut. They were threaded using a tap and die using a ¼ BSW British Standard Witworth.

The pull bar was cut off and threaded with a 16m BSW thread. This will make disassembling in the future easier.

The whole piece was treated in a 10% tannic acid solution in deionised water. Some areas were difficult to reach; it involved flooding and partial immersion of sections to ensure that there is no active corrosion underneath the leaves.

The whole piece was then thoroughly cleaned with IMS to remove any excess tannin, and sprayed with a silver zinc coating, followed by two coats of oil-based red oxide primer. The final colour was chosen because it was the same paint that was used to coat the front gates to the college; it is water-based Farrow & Ball paint and resembles a lead black. Normally oil-based paint would be the best option. The gilding yellow base coat is an oil-based paint mixed specifically for West Dean gates.

The copper alloy bell pull mechanism was disassembled and air abraded. The hooked area was showing signs of dezincification but is still in a stable condition. This was then patinated using a mixed solution of potassium polysulphide and ferric nitrate. This will naturally age better than paint.

I decided to gild the fittings of the piece to highlight some of the decorative features. This will also match the light that is suspended underneath the porch near the pull. For this I used an oil-based yellow paint, the same used for the front gates of West Dean, as my base coat. For the size I used a Japanese quick-dry (the size is the adhesive for the gold leaf); I applied two layers of gold leaf to ensure an overall coverage.

The piece is now finished and back up on the wall of West Dean house please feel free to go and have a gander!

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