58 Australian Wood Review
PROJECTinserting the rods without binding
and the bending of the cauls under
pressure. To measure the caul curvature
required to apply even pressure across
its length I clamped a small block
centrally between two cauls (photo 4).I tightened to an equivalent pressure
of moderate hand clamping^2 giving a
deflection of 4mm at each caul end:
20 of 25 torque setting, low gear
using my drill/driver. Then with a
straightedge I ruled a line 2mm extra
to the 4mm end deflection points
and caul centre. After the caul was
relieved the line was curved and easily
followed all the way with the bandsaw
(photo 5). This was then used as a
template for the other 17 cauls.Torsion box
The torsion box is made from 10mm
marine ply, and the 24mm high core
beams are spaced at 140mm centres.
This arrangement was determined
after careful consideration of tabletop
thickness, weight and strength to span
between the legs. The core beams
interlock each other with slots cut using
the sliding table of the router table
(photo 6). These were cut in batches to
ensure the slots lined up for assembly.The corners were packed with stacks
of plywood cut the same height to
provide a solid side grain for fixing
the legs (photo 7). The tops of two
trestles were set up coplanar using
winding sticks and the glue-up was
done in stages between sheets of MDF
with clamps and weights. I didn’t
use the press for this, as it would be
difficult to keep it perfectly flat.Veneer preparation
The veneers resawn by Greg were
4mm thick ‘providing a durable surface
and the potential for re-surfacing’, he
had explained. After drum sanding the
show side smooth and the other flat
they ended up 3mm. The edges of the
veneers to be bookmatched were then
jointed face-on-back using a track saw
with a fine tooth blade.After aligning the bird’s eye figurings
the veneers were pulled together with- Taping the Huon
pine veneers. - Applying glue to
the edges of the
veneer leaves. - Mixing the
hardener and
colloidal silica
filler for the West
System epoxy. - The glue has to be
the consistency of
‘runny mayonnaise’. - A roller is the best
way to spread the
glue evenly. - Checking
positioning of
veneer layon. - Mating up upper
and lower cauls. - Tightening the
dome nuts, don’t
overdo this. - Routing a rebate to
accept the ebony
inlay for the mitred
frame for the top.
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