Cracks in Forestay Chain Plate Fabrication
The damage of the bow roller shown in the photograph above was found during an Insurance Survey of a 1976 Westerly Berwick, a British built, masthead rigged sailing yacht with cast iron bilge keels.
During the inspection of the rigging chain plates it was found that there were a number of well developed cracks in the two vertical plates that support the bow roller. The photographs show the two cracks on the port side plate. This plate also supported the forestay, therefore the security of the entire rig depended on the strength and integrity of this plate. In consideration of the observation that similar cracks were found on each of the vertical plates, it is likely that these cracks were predominantly due to cyclical loading from the vessel’s mooring chain whilst she was on her summer mooring. The cracks on the port side plate may also be due to cyclical athwartships loading from the jib when she is sailing. There was no evidence to suggest that these cracks have occurred as a result of an impact with an object.
The report recommended that the bow roller fabrication was repaired in order to return strength to the two plates. As this repair would have involved welding, the entire fabrication would have to be removed from the foredeck as the heat generated would have damaged the GRP deck.
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