650 TECH TOPICS
MAST TUNING AND MAINTENANCE FOR CASTLE 650’S
1 Mast Support
Check the mast support system under the deckand down the front edge of the centreplate case to make sure that it is sound and not showing any signs of distortion. This distortion is most obvious when the boat is rigged and tensioned up. The adjacent deck area forms a concave instead of being flat if a defect is present.
2 Mast Base or Plug
It has been known for the pop rivets to sheer and the mast tube to "bell" open and slide over the mast base thus lowering the height of the attachment point of the shroud to the mast.
3 Shroud Attachment Points
Check these points to ensure that no elongation of the fixings has occurred.
4 Spreader Fixings
Check that the spreader fixing points are secure with no movement of the spreader arms at all where they attach to the mast.
5 Basic Settings
These settings are a rough starting point. Measure tension using a Loos gauge (all figures are for 4mm wire).
Mast Rake 310mm
Cap Shrouds 470lbs (= 43 on the Loos gauge)
Lowers 200lbs (32)
Forestay 260lbs (35)