|
Partial or complete restoration consists of returning an object to good
condition while respecting its original appearance. Restoration is necessary
when the surface of an object or its parts shows signs of severe and
irreversible deterioration. Metal, rubber and plastic are most susceptible
to deterioration.
Restoring metal
Metal most commonly deteriorates through active
or inactive corrosion.
Active corrosion:
When metal actively corrodes, its structure is altered. A rapid increase
in the volume of affected surfaces is evidence of active corrosion, which
flakes and crumbles the metal, resulting in an actual loss of matter.
Surfaces affected generally become rough, and orange to brown in colour.
Corroded metal can be treated in two ways: chemical stabilization or
mechanical cleaning.
Chemical stabilization requires tannic acid, an organic acid that reacts
with corroded metal to form a blue-black protective film. Only restoration
professionals should treat an object with tannic acid, since the method is
very complex and requires a base treatment of several chemical products
(including ethanol and phosphoric acid), as well as a long application
process.
Mechanical cleaning can be done using traditional methods such as sanding
and brushing, but a careful, minimalist approach is required to remove rust
without destroying the finish and original wear marks.
Inactive corrosion:
Inactive corrosion deteriorates metal surfaces. It may appear as stable,
superficial rust spots that don't expand. It may also show up as a stable
layer of oxide spreading slowly across the surface. Generally smooth and
ranging in colour from blue-black to brown, this layer offers a protection
leaving the underlying surface intact.
When treating a vehicle, authenticity should be conserved by not modifying
surfaces that show the effects of time, which add an important historical
element. We recommend you proceed as follows:
a) Simply brush the surface without using water, detergent, or abrasive; the
superficial corrosion provides protection;
b) Avoid stripping down to the metal; it will only corrode faster;
c) To eliminate inactive corrosion, apply a few drops of sewing machine oil
then gently rub the affected surfaces with fine steel wool (000 or 0000
grade).
Restoring rubber and plastic
Restoring rubber and plastic is difficult because they are very unstable
chemically and highly sensitive to environmental factors such as oxygen,
pollutants, and especially ultraviolet rays in visible light like
fluorescents and daylight.
Rubber and plastic degradation is unpredictable and begins as soon as the
vehicle leaves the factory. With time the materials lose their resistance
and flexibility, leading to hardening and cracking.
In the case of ultraviolet rays, degradation speed is proportional to light
exposure time and intensity. Recent rubber and plastic products are more
resistant because manufacturers add better stabilizers and additives that
filter ultraviolet rays.
The bottom line on rubber and plastic degradation is that not much can be
done to prevent it. Nonetheless, we recommend that you:
a) Avoid water and soap as much as possible. Instead use a soft dry brush or
a vacuum cleaner ;
b) Avoid ammonia-based products or solvent;
c) Apply standard conservation techniques.
|
 |
|
Active corrosion
Preparation of tannic acid
Mechanical cleaning
Corrosion of metal and deterioration
of rubber
|
|
 |
|
