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Content
George F.Campbell "China Tea Clippers"
Page74   
The background to the tea trade
The homeward passage
Development of the ships
Hull Construction
Appearence
Sail plans
Sails
Masts and spars
Coppering
Steering Gear Arrangements
Windlass and Forecastle Arrangement
Boats
Fife Rails and Bitts
Decking
Rudders
Conclusion

  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.