Agriculture Reference
In-Depth Information
Figure 89
Drilling holes to aid
fixing of the prepared
replacement rubbing
bricks to the body of
the niche. (Courtesy of
Emma Simpson)
voussoirs were cut using the bow saw and a reducing box. This box has a movable
bed that can be adapted to produce ashlared units of varying gauge, as well as to
produce voussoirs by fixing the bed to the required tilt for cutting. A further
templet was made of the moulding of the original voussoirs and this moulding
then had to be cut individually in to each voussoir. The profile was first scribed
onto the side of each voussoir and then these lines were transferred across the
face to mark out the cutting lines. It was decided to cut these shapes entirely
using hand tools: chisels, small saws, files and a variety of rubbing stones. This
method provided the flexibility needed to ease in the old and the new where the
new replacements abutted the three-and-a-half original voussoirs that were to be
retained. As with the work in the main body, distortions made it a difficult job
to match old to new. As well as allowing flexibility, this method would also have
been akin to the original craftsmen's method of producing the mouldings as the
Orangery pre-dates the use of the wire bow saw in gauged work.
Once the voussoirs had been produced, they were dry laid on the full sized
drawing with an allowance for the correct 2 mm joint size. As in the main body,
the decayed bricks were carefully cut out for replacement. As the arch is bonded,
yet no replacements were to be made in the hood, it was decided to partially cut
back in to the hood to allow a 'key' for the bottom bonding header (Fig. 90).
This had to be done very carefully, and the joint faked with coloured mor-
tar in an attempt to minimise the visual disturbance. As replacements built up
toward the vertical position, tie bricks were introduced, again tied using 4 mm
threaded dowel. Finally, a code 4, lead flashing was introduced as further pro-
tection to the arch and hood.
