No. 237 Maritime Archaeology in the People's Republic of China ...

Figure 88. Photograph at the time of excavation showing the various
layers of planking.
Figure 89.
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Sketch of two types of plank joints.
planking being irregularly nailed with light nails to the inner
planking. The garboard strake of the outer planking covers
the seam between inner planking garboard and the keel, with
an additional plank attached to the vertical surface of the keel
as a sheathing.
The rabbeted clinker seams on the inner planking are cut
so that the thickness of the projection of the strake on the
outside is 50 mm. This allows the plank edge of the 50mm
thick outer planking to fit neatly into the clinker step and
form a smooth carvel-like joint. The next strake of the outer
planking is then attached with a clinker lap, the arrangement
is shown in Fig.
From inspection of the grain, the planks appear to have
been whole sawn from logs that were not very much greater
in diameter than the width of the planks. In some cases it
is possible to judge that the face of the plank which shows
timber from closest to the centre of the original tree is used
on the outside face of the planking, but it is not certain that
this was a general rule. There is no sign of charring on the
Figure 90.
View looking aft.
inner surfaces of the planking, so, it is unlikely that heat was
used to pre-bend the planks to shape (this technique is less
successful with conifers than with hard woods in any case).
If the planks were simply forced into shape, the rabbeted
plank edges would be important for holding the edges of the
planks in alignment during assembly. The very gentle curves
of the bow-buttock lines reflect smooth and gentle curves in
the planking which are consistent with the planking bent into
place to form a plank shell in a plank-first constructed hull.
There would be some initial difficulty in forming the required
bend at the end of each midship plank, but the rabbet of the
subsequent strake and the later fastening of that strake by iron
brackets to the adjacent bulkhead would clamp the plank butts
into the required smooth curve. The positioning of brackets in
strakes immediately above and below plank butts is obvious
a deliberate part of the design The details and significance of
this are discussed below.
At the fourth clinker joint on the outer planking, at the turn
of the bilge, a third layer of planking is applied to the hull.
This planking is 25 mm thick and is carvel joined, continuing
for five strakes to the edge of the hull remains. The authors’
impression was that the second layer of planking was reduced
to the same thickness so that the two layers were together the
same thickness as the outer layer on the lower hull, however
this has not been confirmed by measurement.
The rabbeted clinker seams taper into rabbeted carvel
seams towards the bow, presumably to facilitate their entry
into the rabbet on the stem or fore keel. Aft they are carried
right through to the transom. The seam between the garboard
strake and second strake is not rabbeted through the midbody
of the hull, because the angle at which the two strakes meet in
the midbody is too great for a rabbetted seam to be effectively
employed. The bottom edge of the second strake appears to be
fitted to the outside surface of the garboard, but as the sectional
shape changes towards the bow and stern the two strake come
more into alignment and a rabbetted clinker seam develops.
However, the condition of the two strakes is poor and it was
not possible to be sure exactly how they fitted together in the
apparent transition to a clinker joint.
It has previously been assumed that the clinker steps in the
inner planking are fairly close to the steps in the outer planking,
but this is not so. In some places the steps in the two layers are