24 March 2010

conserving heritage furniture

Conserving heritage furniture often challenges us to resolve conflicts between authenticity, minimal intervention and reversibility, and the need or desire for the furniture to continue to be used.

Recently we were presented with a set of such challenges as we embarked on a six-month long project to conserve the heritage Council Chamber furniture from the Sydney Town Hall.

This suite of Australian red cedar furniture was originally made by William Coleman for the Council Chamber of the Sydney Town Hall in 1883. The furniture was built to a design by one of the architects for the Town Hall, John Hennessey.

Photo: Historic image of the furniture in the Council Chamber of the Sydney Town Hall.

Comprising a long D-end table in two separate sections, the Lord Mayoral chair, 17 tub chairs, and 4 long benches (2 curved, 2 straight), all pieces of the suite were showing the signs of having been very well-used over a long period of continual service to the Council.

The tub chairs and benches had been re-upholstered numerous times, most recently in a manner quite different to the original. The legs of the chairs had been substantially modified, with repairs, replacements and extensions, none of which matched the original intent or appearance of the chairs. The tables had suffered mainly due to age and use, as well as through the cutting of holes and slots for telephone and computer cables.

The brief from our client, the City of Sydney, was to return the suite of furniture close to its intended original appearance whilst ensuring that it retained the patina of age and history. In addition, as the furniture was proposed to continue to be used for public events and functions, it was important that the conserved items be functional.

Photos: Tub chair prior to (L) and after (R) conservation

As a result of the original design and fabrication of the furniture, we needed to stabilise all of the joints in the tub chairs, and drew on a range of techniques to do this including:

  • Injection of animal hide glue
  • Dismantling of joints (by unscrewing, as the chairs had no traditional mortice and tenon joints), cleaning and re-gluing
  • Re-securing the screws
  • Installation of large curved blocks to the inside of the seat using adhesive
Previous unsympathetic (and weak) extensions to the legs of the tub chairs were removed. We designed and fabricated new extensions which were milled from old Australian cedar to match the original timber, and which followed the original form based on historic photographs.

We completed an assortment of other treatments in order to rectify damage caused by previous repairs or modifications to the tub chairs.

A decision was made at the beginning of the project to retain one of the seventeen tub chairs in the condition we received it in order to show the range of past repairs.

We decided to replace all of the leather during our conservation works, as none of the extant upholstery was original, nor did it look like the original. The tub chairs and benches were re-upholstered to match as closely as possible the original upholstery based on our interpretation of remnant physical evidence and the historic image above. Most notable is the recreation of the original buttoning.

Upon completion of the physical conservation works, the timber elements were refinished with shellac and waxed.

Photo: Council Chamber furniture after conservation works complete

Perhaps the greatest challenge with this project was resolving issues arising from the well-meaning repair and modification works carried out to the Council Chamber furniture in the course of its 125 year history.  It is likely that few of these repair and modification works would have been carried out with any anticipation that one day this suite of furniture would have such historic significance to the City of Sydney.  We are pleased that we have been able to unravel some of the changes that had occurred over time, to reveal the original form of this imposing furniture.

David West
International Conservation Services

16 March 2010

reversing the damage of a previous restoration

Photo: Overall shot before treatment

A beautifully painted portrait of a lady arrived at our door in a horrendous condition. The canvas had suffered severe shrinkage, the paint layer had been forced together, and having nowhere to go, had lifted away from the canvas forming tent-like shapes across the surface of the painting.

Photo: Close up of paint layer

As we investigated the cause of the canvas shrinkage, we found that a restorer had previously attempted to line the canvas using a water based adhesive. Lining is a procedure where a new canvas is adhered to the original canvas in order to add strength and support. However, we try to avoid lining paintings unless it is absolutely necessary because of the risks involved. Poorly executed lining can cause shrinkage of the canvas with associated damage to the paint layer, but can also change the texture and gloss of the paint layer. When carried out correctly, lining can result in a successful stabilisation of the painting without harm.

As conservators we think a lot about how we are going to treat an object. Often, it seems to us that conservation can be more about knowing what we cannot do rather than what we can. It is very easy to re-touch that missing section of paint, or glue a sculpture back together, but what are the consequences of our actions? In essence, this is what our training and code of ethics are all about – how do we treat the problems with an artwork or artefact whilst maintaining its significance and authenticity, and causing no harm to it now or in the future.

Our treatment of this painting was a lengthy and slow process. Over weeks the adhesive was slowly removed, first by softening it with solvents, and then by mechanically scraping away the adhesive. Simultaneously, we slowly stretched the canvas on an expandable stretcher, millimetre by millimetre. Once the canvas was its original size the tenting paint was then laid back into place.

The varnish layer on top of the paint was also badly damaged from the cracking and needed to be removed. Unfortunately, as the varnish was not a conservation grade varnish, it was not soluble in any solvents that did not also damage the paint layer. Consequently, the varnish had to be mechanically scraped away, which took one conservator three weeks to do.

Photo: After treatment

Finally, we lined the painting using the correct materials and processes, before varnishing, filling of losses and re-touching of damage. The overall results were very pleasing but some evidence of the damage still remains in the surface texture.

Photo: After treatment detail

Projects like this remind us of the challenges our clients face in finding a conservator. Conservators undergo extensive training, and generally specialise in just one field, e.g. paintings or paper or sculpture or metals or furniture / wood or textiles. Most conservators have tertiary qualifications – either an undergraduate or masters degree – and have several years experience on the job working with another experienced conservator in one area of conservation alone. When you find a conservator, it is always worth asking them about their qualifications, area of specialisation and experience, and if they have carried out this sort of treatment before.

Communication is also important so that both you and the conservator understand what you wish to achieve from the conservation treatment, and what the conservator expects the outcome from treatment is likely to be. Returning a painting or artefact to a “new” condition is rarely possible or appropriate, but treating it to bring it into a stable and presentable condition is almost always achievable. Prevention of damage is always far better than a cure, and once you have found a good conservator you can be confident that they have the best interests of your artwork, antique or artefact in mind.

Adam Godijn
International Conservation Services


07 March 2010

on display

As conservators, we are frequently involved in the preparation of objects for display in temporary or permanent exhibitions. This type of work is often challenging, for a variety of reasons, including:

  • Tight deadlines determined by a project manager or exhibition designer ... that don't take into account the practicalities of carrying out the conservation work itself.
  • A complex array of objects, in differing conditions, requiring a variety of conservation treatments.
  • Objects that tell fantastic stories, but that are in such a fragile state or deteriorated condition that it is extremely difficult to prepare them for display.
However, this type of work is also extremely fulfilling, because where the exhibitions are open to the public, we can see the outcome of our hard work, and take our families and friends along as well.

Many of the conservation treatments on objects intended for exhibitions relate to the removal of corrosion and staining as a result of ongoing deterioration so that the object can be more clearly understood when on display, as well as aiming to stabilise the condition of the object so as to halt or slow the rate of that ongoing deterioration.

As well as carrying out the actual conservation treatment, we also need to provide the curators of the exhibition with recommendations for the management of the items whilst on exhibition. These recommendations may include:

  • limits on light intensity to minimise deterioration
  • time limits for display of the object to minimise deterioration
  • need for regular cleaning or re-treatment to manage ongoing corrosion
  • methods of support or presentation that will not stress the object
Finally, we are often asked to fabricate mounts to support the objects whilst on display. This requires both an understanding of the condition of the object, and the exhibition designer's aim in displaying the object. Sometimes these requirements are in conflict, and we need to work with the exhibition designer and curator to find the optimum compromise.

Last year, International Conservation Services undertook conservation treatments on more than 150 objects destined for the new permanent exhibition at the Anzac Memorial in Hyde Park, Sydney, which was opened in November. We also prepared mounts for many of the objects.

These objects included a wide variety of wartime memorabilia and ephemera. We found this project particularly challenging because of the unexpected emotional impact of many of the objects.


In particular, working with documents such as the telegram above provided an immediate window into the emotional impact of the war on families.




The WWI miniature medal illustrated above before and after conservation had been adhered into a storage pocket. We removed it from the pocket, and carried out the following treatments:
  • cleaned with ethanol and degreased with white spirit
  • metal polished with silver cleaning cloth
  • tarnish removed with solution of thiourea in water
  • medal coated with clear lacquer to minimise tarnishing whilst on display
  • loose threads on ribbon cut, and ribbon stitched back into shape
One of the more intriguing objects we treated was this artificial leg.





A combination of rubber, wood, aluminium, copper alloy, iron alloy and canvas, it presented us with a range of challenges. Our treatments comprised:
  • brush vacuuming of the entire object
  • cleaning of iron alloy components (hinges) with white spirit, fine steel wool, and tannic acid removed with ethanol
  • cleaning of copper alloy components with a combination of dilute solutions of triammonium citrate and citric acid, and thiourea, along with mechanical methods (bamboo skewers and scalpel)
  • coating of metallic elements with microcrystalline wax to reduce the rate of ongoing corrosion whilst on display
  • reattachment of lace-up hooks

David West
International Conservation Services