Restoring the case of an antique clock often requires a number of
skills beyond those used in basic wood finishing. There are
several "special" finish techniques that every restorer should be
able to perform.
For example, gold leaf (gilding)
was used extensively by many clock makers during much of the
1800's. Gilding was often used on the end caps of columns and on
molding trim around glass. Complete column gilding was sometimes
used and "rings" were impressed around the circumference of the
column. Repairing and restoring gilded finishes is an essential
skill for high quality restoration work. A brief example of
Gilding of columns is detailed in this link. Chapter 6 of Extreme
Restoration provides a more detailed explanation.
finish was faux
“tortoise shell” or “French ivory”. This was a frequently used
treatment on the columns of shelf clocks. The original finish on
many clocks shows exceptional depth to the shell effect.
Recreating this finish is not difficult but requires a somewhat
Less common, but equally
challenging, is the “simulated” wood finish
used on the sides of a number of clocks built in the later part of
the 1800’s. This finish is much more common than usually
When only a
portion of a veneer panel must be repaired or replaced, it can be
quite challenging to match the old and new. This often requires a
special technique commonly called "faking".
This is a technique for making unwanted veneer joints disappear
and blend with the panel. Faking is not difficult, but does
require practice and a good eye.
"Special Finishes" has over 70 pages dedicated to restoring or
recreating the most common special finishes used on antique
American clocks. This includes gilding of columns and trim,
tortoise shell finish and faux wood grain. Mastering these
techniques will push your restorations to the next level.
Understanding The Different Types of Gilding
Gilding or gold
leafing is an ancient art going back over six-thousand years.
Egyptians were well versed in gilding as can be seen on artifacts
recovered from ancient tombs. Ancient oriental artifacts show that
gilding was also practiced in this part of the world from very
The use of real gold
as well as imitation gold leaf (Dutch leaf) was common throughout
Europe from the early middle-ages forward. Gilding was used for
books, religious objects and in the homes of nobles.
Gilding was integrated
into American clock case designs during the early to mid 1800’s to
fit in with the Empire and Victorian furniture styles of the
Columns were often
gilded as was the quarter-round molding around the glass in the
door. The feet, side-arms and metal trim pieces used on
black-cased clocks of the late 1800’s were usually gilded.
There are a number
of different materials used for gilding. Both real gold leaf and
imitation gold leaf have been used. There are also several
different techniques that can be used for gilding depending on the
materials being used and the finish desired. Understanding the
available materials and techniques is the first step in
determining the best approach for a given project.
Gilding with real gold offers one big advantage over imitation
leafs: the finished surface will not tarnish or turn greenish over
time as oxidation takes place. Gilding with gold leaf can be
accomplished using one of two techniques.
This is the original and oldest gilding technique. This technique
uses a surface on which multiple coats of gesso have been applied
then sanded glass smooth. Next a red-clay “bole” is mixed into a
paste and applied to the gesso. This finish is also carefully
sanded and polished.
Finally, the gold leaf
sheets are carefully applied using a water/alcohol/size mixture to
accommodate laying the sheets.
A special gilding
brush is used to pick up the gold sheets and apply them since the
gold leaf is far too thin to be picked up by hand.
An advantage of water
gilding is that the gold finish can be burnished to a high luster
resembling a single solid piece of gold.
water gilding was not the technique commonly used in American
clock manufacture. The process was far too time consuming and
This is a technique in which actual gold leaf is applied using a
“size” or glue mixture to hold the leaf in place. With this
technique, the wood is prepared with a gesso mixture as with water
The gesso is smoothed then covered with the sizing liquid. A bole
coat is usually not used. The gold leaf is applied using the
gilding brush and is held in place by the size.
This technique is much
easier to master than the water-gilding technique, but cannot be
burnished to the high finish of water-gilded pieces. However, oil
gilding applied to a very smooth surface can produce an excellent
finish. Oil gilding is often used on large scale and
It is generally
thought that gilding using real gold would have been too costly
for mass produced clocks. This can be verified by closely
examining the remaining gold finish on a clock case. Real gold
does not oxidize and become dull and greenish. This is a quick
indication that the finish was originally an imitation leaf.
Imitation-leaf: Gilding using a
non-gold leaf has been around since at least the 1500’s as a
decorative replacement for costly gold. There are a number of
different types of imitation leaf including:
(alloy of copper and tin).
Ducat Gold (alloy of
copper and aluminium).
White Metal (alloy
of copper and aluminum).
Dutch metal (alloy
of copper and brass).
Dutch metal leaf is by
far the most common alloy used in gilding and is still commonly
employed for gilding today. It is the most likely gilding
material used on antique American clocks.
Imitation leaf is
supplied in leaf form (small squares) just as real leaf. A “book”
of leaves is a package of leaves separated by tissue paper. A
number of different brands of imitation leaf are readily available
from arts and crafts stores as well as from numerous internet
There are several recently developed gilding products which
using the copper/brass composition seen in imitation leaf, but
using a much finer mixture than previously possible. A very thin
layer of this mixture is deposited on a transfer medium such as
cellophane. It is then transferred from the cellophane to the
object being gilded via a standard sizing solution.
Imitation leaf and
transfer leaf both have advantages and disadvantages. Imitation
leaf is available in many different brands and shades. Finding a
color that closely matches that of the original clock finish is
usually possible. A disadvantage of imitation leaf is that it is
applied as individual overlapping sheets. This usually means that
small lines will be visible on the piece where the leaves
overlap. Carefully planning and applying the individual leaves
can usually minimize visible leaf joints but this is still a point
Transfer leaf offers a
different concept than imitation leaf. The gilding material is
lifted from its cellophane backing when applied to the work
piece. This means that there will be no joints between leaves.
Transfer leaf applied to a smooth surface creates an almost
mirror-like finish close to a piece that has been water-gilded
with real gold then burnished. The negative side of transfer leaf
is that there are fewer brands available and those available tend
to have a more “brassy” or yellow look than either real gold or
good imitation leaf.
Another thing to
consider when choosing the leaf type is the end result desired.
Traditional imitation leaf is a solid sheet of material. When
applied it usually provides 100% coverage of the underlying
surface. This can result in an “over-restored” or “too perfect”
look. On the other hand, transfer leaf is applied by pulling the
material from the backing. Often there will be small un-gilded
spots which allow the under coat (usually red) to show through.
This creates a more aged look.
Both types of leaf can
provide a very good gilded finish for clock restorations. They
are inexpensive and you may want to experiment with both.
An alternative to the use of gilding or leafing
materials is metallic powders. Metallic powders are very finely
ground materials such as mica or other minerals. There are many
different shades of powder available. In fact there are over six
different shades of gold alone. This makes matching an existing
tone much easier.
Metallic powders are
applied to a surface that has been prepared with an adhesive size
similar to that used with leaf.
Metallic powders are
very versatile and can be used to make a liquid paint or brushed
on dry. The wide range of colors is very appealing.
note about imitation gold leaf and powder products; whether imitation leaf, transfer leaf
or metallic powder, they must be sealed with a clear coat soon after
the gilding is applied. If not, the finish will very quickly
begin to darken and tarnish as oxidation takes place.