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The braces
were set at 90° to the axis of the pintles, and the arms or straps
in the sternpost extended over some of the hull planking, sufficiently
to take about two bolts in the upper and three in the lower in addition
to three bolts in the sternpost. The heavy strain and sudden shocks on
the rudder often caused leakage through the boltholes in the planking,
and by the 1860s the braces were being made shorter so that all the
bolts were contained in the sternpost. The upper strap was made in a
tee shape to accommodate the three bolts if the post was narrow,
although the lower one could extend onto the planking because its bolts
were in the solid timber of the deadwood. This became a rule under
Lloyd's in 1867 so all ships built to their rules after this date would
have braces in this manner .
This does not mean that vessels before 1867 did not have this
arrangement, as it was frequently the case that a good shipbuilder
would solve his own problems and Lloyd's would adopt the solution once
it was proven. Some draughts
of American ships in the early 1850s indicate short braces on the post.
There were usually four sets of braces to the tea clipper of all sIzes.
To prevent the rudder unshipping accidentally, the upper pintle
had a woodlock nailed or screwed beneath it. This was a block of
hardwood on the front of the rudder below the sternpost gudgeon which
prevented the rudder from lifting. Rudders with the major width near
the heel had slight buoyancy, being made of wood, and tended to lift if
the stern was deeply immersed in a following sea. Fairing pieces were
also nailed above the pintles on the front of the rudder to keep them
in place.
The iron plated rudders conformed to similar contours to the
wooden ones, but of course were much thinner. A basic wrought iron
frame combined the stock and the gudgeons in one unit; some of the
early ones had the pintles incorporated into the framework. Iron plates
were riveted each side over the frame with the edges let in flush. The
hollow spaces inside were filled with greenheart or oak chocks in
pitch. The gudgeons on the stern frame were also incorporated into the
frame, and the narrow confined space inside the hull in the deadwood
area was filled in solid with a cement mix, as the riveting in this
area was difficult and often defective.
Designers and builders had differing ideas about the best
contours and areas for the rudder shape, some preferring the greatest
width near the top, others in the middle, and some near the heel. This
depended on where it was considered that the run of water following the
lines of the hull was most effective and clear of eddies, especially
with the vessel heeled.
The old fashioned type of hull with a heavy transom and a full
shape near the waterline dragged a body of slack water behind it in
which the rudder was not very effective, so that its maximum width was
in the lower portion where there was a cleaner flow of water. This was
the type of rudder seen on old naval draughts or those of East
Indiamen, with the bottom almost square and then tapering upwards in a
straight line with steps to the stock.
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