The rig tension is measured with a rig tension gauge – the “Loos” variety is the best,
attached to the shroud approx 1 metre up from the deck.
The lower shrouds restrict further prebend, and usually show around 100150kgs tension
with the mast snug at the front of the gate.
The webbing mast strap should now be used to hold the mast to the front of the gate:
Ease the adjusting screw, wrap the strap around the mast and kingpost – under the
deck – and shackle it up. Tension it up by hand and then with a spanner, ensuring it is
as high as possible under the deck. It should feel tight and the mast solid in position.
Make sure only the webbing is in contact with the spar, NO part of the shackles or
buckles should be touching the spar. (As in Fig 2). Also make sure the webbing strap is
tight up against the foredeck at all times, so not to interfere with the halyards. (As in Fig
3) The strap may be left like this all season, but you should maintain at least 150kgs of
rig tension at all times, whilst the strap is fully tensioned. This is a sensible amount to
leave on the boat in any case to avoid “slopping around” on an unsettled mooring.
HINT:
As the mast is effectively fixed at deck level, the adjustment of the
shrouds becomes paramount: the more the shrouds are wound
down, the more pre-bend as well as rake you will have. This will
de-power the rig. The less the shrouds are wound down, the
straighter the mast as well being less raked, and this will power up
the rig.
