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The standing rigging provides a quite 'predictable' mechanical platform for the sails. All such wire is elastic and a windloaded sail on a foil or attached with hanks will quite predictably cause wire sag under this 'load' from the sails.
The luff shape of all jibs/genoas that are attached to forestays, etc. is not 'straight' but are cut to compensate for the sag in the wire that develops due to a wind-loaded sail - called 'luff hollow', a smooth curved shape cut from the leading edge to compensate for the wire sag.
A sailmaker 'depends' that the rig tension be quite close to the OEM values set up by the designer - usually 12-15% of wire tension for sailing in 12-15kts. Replacing rigging with 'stronger or thicker cross section' rigging wire, will cause more SAG of the wire to occur. The net result is that if you increase the 'strength' of the wire (and the new 'heavier' rigging delivers the same force into the boat), you will have to have all your jibs/genoas 'recut' so that the sail leading edge shape will match the NEW and different sag that develops in the wire.
Here's a more detailed explanation of 'matching' the sag in the forestay, etc. wire to the 'luff hollow' shape of a jib/genoa: http://www.ftp.tognews.com/GoogleFiles/Matching Luff Hollow.pdf
The luff shape of all jibs/genoas that are attached to forestays, etc. is not 'straight' but are cut to compensate for the sag in the wire that develops due to a wind-loaded sail - called 'luff hollow', a smooth curved shape cut from the leading edge to compensate for the wire sag.
A sailmaker 'depends' that the rig tension be quite close to the OEM values set up by the designer - usually 12-15% of wire tension for sailing in 12-15kts. Replacing rigging with 'stronger or thicker cross section' rigging wire, will cause more SAG of the wire to occur. The net result is that if you increase the 'strength' of the wire (and the new 'heavier' rigging delivers the same force into the boat), you will have to have all your jibs/genoas 'recut' so that the sail leading edge shape will match the NEW and different sag that develops in the wire.
Here's a more detailed explanation of 'matching' the sag in the forestay, etc. wire to the 'luff hollow' shape of a jib/genoa: http://www.ftp.tognews.com/GoogleFiles/Matching Luff Hollow.pdf