THE CONSERVATION AND RESTORATION OF THE HEREFORD SCREEN CONSERVATION

	Structural coherence had been lost when the dismantled screen arrived at the V&A. At the beginning of the project the screen consisted of around 14,000 separate pieces. Many decorative parts were loose or even missing. The originally vivid colours of the painted elements were muted and disfigured by rust and much of the paint was flaking off. Not all materials were badly damaged – timber and hardstones were least affected – but themosaics were in a sad state of decay. Gilded and painted ironwork, lacquered and polychromed copper, brass and zinc are some of the metals used on the Hereford Screen.
To create a diagram of the reconstructed screen a full stereophotogrammetric survey was taken of all the parts (a photographic technique that produces accurate three-dimensional images to scale). The parts were reassembled using computer drafting. The diagram enabled a programme to be drawn up for each stage of the conservation, restoration and reconstruction of the screen. Conservation specifications were developed by Diana Heath, Head of Metals Conservation, at the Victoria & Albert Museum.
Restoring the screen is the Museum’s largest conservation project to date, in both scale and cost. The cost, over £800,000, has been met thanks to the generosity of private individuals and trust funds, with matching support from the National Heritage Memorial Fund. Thirty-eight conservators have cleaned, painted and reassembled the screen, over a period of thirteen months. To reveal the sound metal below the loose, flaky or pitted surfaces, air-abrasion was used. Fine jets of abrasive powder (aluminium oxide) were sprayed over the surface to produce a bright finish. The iron and copper surfaces werepainted with a metal primer and an acrylic consolidant (paraloid B72) – these isolate the modern restoration from the original painted surface, so that all added painting is reversible.
Scott designed the screen to be freestanding at the 1862 Exhibition. The upper structural parts were made of timber. To ensure its stability in the Museum a foundation of steel girders has been built inside the base plinth and thick steel rods fitted inside all of the columns, bolted to the girders and fixed on to steel plates inside the entablature.
		Top Wrought iron tracery arch showing the restored paint and gilding scheme and the intricate assembly of the parts. 2nd row, left to right Base plates for the columns.All cast iron structural elements have been ultrasonically tested for fractures and some areas strengthened. Stencilled polychrome paintwork on the cast iron columnbases was added when the screen was installed in the Cathedral in 1863. Conservators studied and recorded the whole screen to establish exactly the first Cathedral colour scheme. 3rd row, left to right Threaded steel rods have been introduced into each hollow column and pass from the plinth to the entablature to ensure stability of the re-erected structure. Brass decorative elements were cleaned in specially designed micro-air abrasive units using aluminium oxide powder to remove old shellac and all corrosion products. The cleaned items were then carefully repolished and lacquered. The 126 mosaic panels were cleaned and consolidated. Some new tesserae were cut from clearor brightly coloured glass with gilt backing.
		Top The Cresting shows the intricate polychromy. 250 paint samples were taken during the dismantling and analysed under microscope to establish the paint layer sequence. 2nd row, left to right Polished brass, painted and gilded wrought iron and copper decoration re-assembled around the painted exposed section of a cast iron column. The Mosaics contain a mixture of marble, stone, glass and polished brass tesserae with mortar backing set in a steel frame. Detailed analysis identified pigments and paint media. 21 differentcolours of lead oil paint were mixed for refinishing. 3rd row, left to right A delicate wrought iron monogram letter on the rear of the screen. Each of the 13,703 items was labelled and recorded before cleaning. Conservators checked and repaired all the oak and pine timber elements. This view shows careful patch repair of the cross prior to refinishing. Copper decoration was also cleaned with micro-air abrasion to remove corrosion, dirt and loose paint before repainting with red lead oil paint.
		Top The wrought iron scrolls, foliage and roundels were carefully dismantled and cleaned locally to remove any traces of rust. Surviving areas of original paint were isolated with an acrylic consolidan tbefore painting. 2nd row, left to right Hardstones were fixed into zinc settings and mounted onto wrought iron decoration or brass sheet panels. All existing hardstones required cleaning and resetting. The polished brass ‘roof tiles’ were cleaned, re-polished, partially painted and lacquered prior to refixing in place on the timber entablatures. Some small polished hard-stones were mounted in polished brass settings mid-way up the columns. 3rd row, left to right Painted iron elements, once dismantled and cleaned, showed evidence of the changes in the decorative scheme. Timber elements showed polychromatic and stencilled decoration similar to the iron elements but the paint was in better condition when cleaned. Individual gilded, cast, decorative items awaiting assembly onto the iron trefoil arches which span between the column capitals.
Return to Introduction Hereford Screen Hereford Screen History Sir George Gilbert Scott (Architect) Acknowledgements