Series editors' preface - Wood Tools

to the substrate or by using paper to accentuate
the colour of the tinted adhesive. Pigment
analysis has identified the use of vermilion
(mercuric sulphide), lamp black, smalt and
copper resinate (Umney, 1993). Gold leaf may
sometimes be found under turtleshell.
Differential movement between veneer and
substrate or within the construction of the
substrate can cause several problems. Some,
such as loss of adhesion, may be relatively
simple to fix whilst others, such as warping or
stress cracks in the veneer over cleated joints,
may have no completely satisfactory solution.
Stress cracks are usually caused by low RH
and if this problem cannot be addressed there
is little to be done apart from consolidating
the veneer as it is found. Checks and splits
will reoccur unless fluctuations in RH are
minimized. Attempting to prevent movement
of the substrate using dowels or butterfly keys
may result in merely extending the area of
damage in the future and it is important to
balance a desire for perfection against the
inherent properties of the original material.
Cracks caused by fluctuating RH and exacerbated
by compression set may accumulate
dirt, wax, and are vulnerable to discoloration
from the oil component in traditional furniture
revivers.
The use of decorative inlay in furniture has
a rich and varied history. Inlaid furniture dating
from the eighth century BC was excavated from
Gordion, Turkey in the 1950s. Moorish craftsmen
on the Iberian peninsula produced an
array of inlaid objects in the tenth, eleventh
and twelfth centuries. The Italian decorative
form tarsie (plural of tarsia) developed in the
fourteenth, fifteenth and sixteenth centuries. It
was the source of the popular sixteenth and
seventeenth century English decorative form
now known as intarsia, although inventories
from the period often refer to such decoration
as ‘markatree’ (Edwards, 1987). The outline of
an intarsia design was cut into the surface of
the wood, waste removed to a depth of around
1 ⁄8 in (3 mm) before wood (holly, bog oak, fruitwoods
etc.) or other materials (ivory, bone,
turtleshell, mother-of-pearl) were inlaid into
the surface to create a decorative effect.
Replacement of losses uses the same techniques
for creating a template described for
marquetry and boulle, though the repair piece
itself will be of a thicker dimension. Wilmering
Principles of conserving and repairing wooden furniture 471
(1998) has described the conservation of
fifteenth century intarsia panelling.
10.4.1 Laying veneer
There are several methods of laying veneer
onto a wooden substrate. Hammer veneering
can be used to lay knife-cut or rotary-peeled
veneer on flat surfaces or those that curve in
only one plane. Thick saw-cut veneer or
complex curves were veneered using shaped
cauls. Shrinkage as the glue dries will cause the
substrate to bow unless it is firmly fixed to a
frame or counter-veneered. The substrate
should be level and free from defects.
Traditionally the surface was scored with a
toothing plane.
Hammer veneering requires a warm draughtfree
workspace, freshly made slightly thinned
animal/hide glue, a supply of clean hot water,
a clean undyed rag, a veneer hammer, veneer
tape and pins, and an iron. Veneer hammers
have a 4 or 5 inch (100–125 mm) non-ferrous
tongue that is slightly rounded at the edges to
prevent scoring the veneer as the glue is forced
out. Smaller veneer hammers or a Warrington
pattern hammer may be used for crossbanding
and stringing.
Sheets of knife-cut veneer, which are usually
around 0.7 mm thick, may be laid by hand, one
at a time in a two-stage process. Firstly, hot
animal/hide glue is brushed evenly over the
substrate and the veneer placed on it. A little
glue is brushed onto the surface of the veneer
to lubricate the action of the hammer, which is
worked in a zigzag pattern over the whole
surface, working from the centre of the sheet
to the edges, in the direction of the grain. This
brings veneer and substrate into close contact
and forces out some of the excess glue (Figure
10.22a). In the second step, a dampened rag
is placed on the surface and a hot iron used to
soften the glue. The iron should be hot enough
to melt the glue under the veneer but not so
hot that it scorches the wood. A workable area
(maximum c.45 cm square) should be steamed
and the veneer hammer used a second time, in
the manner described above, working from the
centre out the edge, with overlapping strokes,
to force out the last of the excess glue. The
hammer is worked along the grain of the
veneer because the veneer will stretch and may
break if force is applied directly across the