Velsheda
New teak deck laid for Velsheda using SP370 adhesive 04th September 2006
Velsheda, the J Class yacht, has recently returned to SYS (Southampton Yacht Services) in the UK for a major refit which has included the installation of a new teak deck. SP370 teak deck adhesive has been used to bond all the teak to the structural sub deck.
Charles Nicholson designed Velsheda in 1933 and she was his second J class design to be built at Camper and Nicholsons. Her owner, Mr W. L. Stephenson founder of the Woolworth's chain of stores, raced her extensively during the 1930s and achieved an enviable number of firsts especially in her second season's racing.
Since these glory days, Velsheda has had a varied life including considerable time spent as a houseboat on the Hamble River. She was eventually rescued and following a basic refit was used for charter around England's south coast. She was then sold again to an owner who had the resources to order a complete re-build in 1996 by SYS.
Velsheda was originally built of steel and part of the SYS refit involved replacing much of the hull plating. The steel sub deck was replaced with one of aluminium, saving weight high up in the structure and allowing weight to be added below in the form of a fully fitted interior. A far cry from her original specifications as J's did not have engines or any of the equipment that is now incorporated in a luxury yacht.
The aluminium was sheathed with plywood and as with the old teak deck, the new teak was bonded to the plywood with SP's SP370 teak deck adhesive. A vacuum bagging infusion technique was not suitable to use owing to the fastening holes for the many deck fittings that had been removed. Instead, SYS devised an innovative system of metal bars and wedges to apply pressure to the teak strips that were bonded in threes.
Firstly, temporary blocks were bonded to the aluminium sub deck with a spot adhesive supplied by SP. The metal bars were suspended across and fastened to the top of the temporary blocks and then wedges were used between the metal bar and the top of the teak strips to apply pressure. Once the SP370 product had cured, the wedges, metal bars and the temporary blocks were removed.
SYS chose SP370 teak deck adhesive because it has been formulated to be thixotropic in order to have good gap filling properties but it is also squeezable. This allows the adhesive to spread when pressure is applied therefore minimising voids in the glue joint. With a lap shear strength of 24-28Mpa and cleavage strength of 7-9Kn SP370 is a high strength, tough adhesive system and with its 1:1 mix ratio offers simplicity of use and minimal waste.
