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Home arrow Conservation & Restoration arrow Conservation vr Restoration
Conservation vr Restoration Print E-mail
By John Osborne FSG

A gun is a technological functional object which is built to perform a function by moving parts, electrical current etc. Guns come in various types, shapes and sizes including aircraft guns, air guns, field guns, hand guns, laser guns, machine guns, ships guns, shot guns, etc. A gun’s technology is reflected in its parts, materials, metallurgy, manufacture and use. There are technical, ethical and practical problems of technological functional object conservation/restoration. It must be decided what is to be preserved; the material or its function.

Keeping a gun in use or in non-maintained storage puts it at risk and compromises the material evidence. As a preserved collection artefact it can no longer be seen to work.

The ideal condition of a technological functional object such as a gun, is to present it as it was when last in use or operation. Complete, still in working order and retaining its natural character.

This is the condition we should try to maintain it in. An important criterion for assessing the authentic natural character of a gun is the identity of the gun with its patina. This is the sum of all the changes that the gun has undergone over the years resulting from oxygen, humidity, light and air pollution, as well as of use, marring, wearing and compressing the surface material. These together with dust and so called environmental influences, create a surface that makes an object appear old. The patina may easily be destroyed by ill considered restoration measures.

The surface is a very important and representative part of a gun. Each gun has its own history. Traces of its production, age and past use, as well as other changes produced by its history are not things which mar the gun’s aesthetic appearance, and consequently should not be erased.

Unless there is good reason for carrying out restoration it should not be done. A reason for restoration – which is not a preservation process but rather a display technique – is to get the gun operational again (or aesthetic) which will change the gun’s appearance.

A growing number of poorly preserved and therefore inexpensive guns are being drastically repaired and refurbished to look well preserved for the commercial market. The purchaser, however, is buying a decorative item, and is being deprived of the authentic character and hisjtorical value of the original.

If replacement parts are to be made they should be able to be removed without leaving a trace. Irreversible measures should be avoided.

In the past the non-scientific approach, general remedies, gunshop technique, tradition and intuition mean that often guns have been over-treated or ims-diagnosed. Much information about a gun can be lost or distorted by a sloppy restoration approach.

The scientific conservation approach is gaining acceptance as a logical way to look after the vast and growing collections of guns and other technological functional objects.

TREATMENTS

No treatment should start until a gun has been thoroughly examined and a treatment proposal prepared. Every part should be examined using the best techniques available and where applicable should include ultrasonic imaging, optical and electrochemical analysis.

All treatment should be the minimum required to estabilise a gun in the display or storage environment with adequate maintenance and monitoring. The worse the display or storage environment the higher the maintenance level.

All new treatments should be verified by testing, then subjected to professional scrutiny, and the results and technological information subsequently published.

A gun or any functional object (even an automobile or aircraft) wrapped in a sealed plastic bag can be stabilised by connection to a dehumidifier, which will remove the moisture in the surrounding micro environment. Restoration is not essential when preservation is the overriding goal. Restoration can be death to history. Documentation is vital for determining the object’s rate of deterioration. Archival black and white photography is one simple method of monitoring condition, and smaller objects can also be weighed.

Surfaces of wood, leather, rubber and plastic are best cleaned with a damp cloth with, if necessary, a little soap added to the water. A light waxing will care for all lacquered or painted surfaces.

Brass, bronze, copper, aluminium, pewter and zince need only have the surface soiling removed, mechanically if necessary. This permits spot treatment and partial removal. Do not use chemicals; these cannot be easily controlled.

Chrome and nickel seldom corrode, but are often raised by corrosion of the undermetals. Chromed and nickelled surfaces damaged in this manner will have to be accepted, just as any recoating must be rejected.

Silver is a special case because usually no cavities show after removal of the dark sulphide and oxide layers of tarnish. The original appearance of fine silver can be restored with relatively little loss of substance. Chemical means may be used to remove the layers of tarnish. Extreme care is required with thin layers of silver plate which have undergone complete chemical conversion. These should not be treated.

Gilded copper, brass and bronze surfaces may become covered with green copper salts. If these copper salts are dissolved by chemical means, the layer of gold is usually recovered relatively unimpaired. Gilded surfaces that have no unsightly corrosion products should not undergo chemical treatment and should not be cleaned with ammonia water.

Besides dry removal of filth by vacuuming and brushing, textiles require special cleaning tailored to suit each individual case.

During cleaning it is essential to make sure that no single part of a gun or accessory is cleaned too much.

Rust should not be removed by chemical means, such as rust removers or rust converters. They generally give the iron or steel an unnatural colour and remove the rust in the cavities of the attached surface which leaves an unnatural impression. Superficial rust may be rubbed off with a rag soaked in benzene, petroleum or oil. Any rust remaining in cavities gives no cause for worry.

More resistant layers of rust can be removed mechanically by synthetic fleece polishing but leaves no visible traces of the polishing process. Blued and browned surfaces damaged in this manner will have to be accepted, just as any re bluing or re browning must be rejected.

Areas of thicker encrustation may be removed mechanically or flaked off. Whether to leave or remove corroded layers must be decided case by case. Corrosion products are usually not nodes from which further corrosion spreads. Exceptions are rust saturated with chlorides, guns salvaged from the sea and excavated objects of bronze and other metals with high chloride content in the corrosion layers. These need special treatments tailored to suit each individual case.

Progressive corrosion has rarely been observed in ferrous metals (even under compact layers of rust), and in non ferrous metals in indoor environments with less than 50% relative humidity, even without application of protective coatings and/or corrosion inhibitors.

Shiny, blued or browned ferrous gun parts are prone to rust in rooms with average humidity; they must be protected with inhibitors grease, oil, wax or a coat of lacquer.

Colourless lacquer as protection against corrosion should only be used after long deliberation. Every new coat detracts from the natural appearance of the surface and thus diminishes experiencing the authentic gun.

Wax based coatings are preferable to urethane coatings which are very difficult to remove.

Acknowledgements:

David Hallam    Australian War Memorial
Kate Roberts    Museum of New Zealand
George Hardie Jnr    American Aviation Historical Society
Herman Kuhn    Deutsche Museum Munich
 

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