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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
 

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My question still lingers. ..................... Do I stay with the materials I have or do I scrap it and buy new smaller stuff?
1/16" difference in wire diameter isnt going to make that much difference on a 'coastal' or 'inshore' design boat. Just set up to PROPER tension and observe, especially observe the amount of 'sag' in the forestay when beating in ~15kts.
If that isnt satisfactory, look at similar boats with similar weight/sail area/depth and imitate their wire sizes - Pearson 26, Catalina 27, etc.

Dont 'guess' with rig tuning.
Racing boats sail much better, heel over much less, are less 'cranky' and are 'safer' because they usually have precise rig tension adjustment.

Here's probably the most comprehensive rig tuning guide available on the internet, including how to precisely set up proper tune (including 'pre-bow') WITHOUT a tension gage: http://www.riggingandsails.com/pdf/selden-tuning.pdf
A SUMMARY of that rigging manual is presented here on Sailnet by Guiletta: http://www.sailnet.com/forums/gear-maintenance/42542-adjusting-your-rig.html

Dont guess with rig tension. ;-)
 
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