Modifications to Shrouds on the
twisted cord used for the shrouds poses some problems. The
cords tends to untwist under tension and causes tangles around
the bowsies used to tension the cord. The cord also
stretches under load which does allow gust shock load to be
absorbed but also makes it difficult to keep the mast vertical.
Anyway the self-righting forces are not great so heeling absorbs
the gust shock loads readily.
Much better to use a cord with no (or little) stretch.
Dyneema as used by fishermen or kite enthusiasts is the
preferred cord. This material is braided and has no
tendency to twist under load. Its stretch under load is
also very small. As there is little or no stretch in the
cord making sure it is tight with no slack can be a problem with
a simple bowsie with a 2:1 purchase around the chain plate
fitting. A much better idea is to terminate the shroud
10-15 cm above deck height with a loop or better still a small
brass or stainless ring and use another length of cord looped
through this to make a 3:1 purchase.
Cord can be obtained from fishing supplies, kite shop or the two
RC Yachting suppliers on the links page
Ben has a significant supply of cord he is willing to share.
Wire and special adjustable turnbuckles would represent an
alternative method of creating shrouds. Wire fishing trace
or special wire from the RC suppliers would suit. The
suppliers also have turnbuckles or you could be adventurous and
make them yourself.
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