mately 55°. The groove should straddle the crack all the way down to the
gesso preparation; short, individually fitted wedges are then inserted into
these grooves. The grooves should be made as deep as possible without
causing damage to the paint layer, so as to avoid the formation of hairline
fissures (see Rothe, “Critical History,” herein).
The type ofwood used to reconstruct these panels should be well-
aged material of the same type as the original painting support. The vari-
ous chisels used, including a pointed chisel for the finishing of the V-shaped
grooves, must be maintained in constant sharpness (Fig. 5). If percussion
is needed, the ball of the hand (never a mallet) may be used. In some
instances, when the cracks are straight and long, two angled planes are
used—one for the left side of the split, the other for the right side (Fig. 6).
Before the wedges are inserted, the detached sections of the panel
must be perfectly flush with each other. This is accomplished by a simple
system oftemporary braces, or tiranti,that are screwed into the panelF S S T 309Figure 5
Some tools used in the preparation of
V-shaped grooves.
Figure 6
Two angled planes, sometimes used for
preparing long, straight grooves.