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Old 30-01-2011, 21:46   #31
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Say, maybe putting a code Zero onto Charlie's boat would give him the added power that he seeks (at least off the wind a bit). Some pricey hardware, but lots of sail area and easy usage.

Whaddya think Charlie?

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Old 30-01-2011, 22:31   #32
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Quote:
Originally Posted by Charlie View Post
I like that idea of adding Roach I also have a longer boom so between extra roach and the longer Boom I might be able to make this work w/o as much $$$

She's not a tender boat at all. I wouldn't be moving the Center of Effort fore and aft but vertically I would be. As I said above the first reef would take the boat back to original conditions and with the small jib I am good till about 25 knots. Then I have the choice of a second reef or rolling up the jib and setting the staysail.
If you add roach you are going to change the helm balance, you are adding sail area at the aft end of the boat.

If you increase the main size by increasing the mast height without increasing jib size (as OP initially proposed) you are going to change the helm balance. The total CLE is a weighted average of the Main's and jib's CLEs, so changing only one changes the location and magnitude of the total CLE.

If you increase the mast height, and allow both the main and jib to increase there will probably be a slight change in the fore and aft location of Total CLE that would probably correctible with rig tuning. In the this case the increase in one CLE is offset mostly by the increase in the other's CLE.
The only way I can see to do this without spending wheelbarrows of money is to convert the existing mast from keel stepped to deck stepped. A rigger could weld the sail groove back where it was cut for the sail entry, and at the goose neck. Then you would need to consider the spreaders.

If you remain with double spreaders and respace them on the mast, the panel lengths between shrouds/spreader will have been significantly increased and you will have lost the support of the deck level blocking. A navel architect should look at that to determine if the existing mast can take it. The chain plates will also need to be considered, but they are probably fine as is.

The other option is to go with triple spreaders. The panel lengths will decrease, even with the extra 6' of mastheight and the lack of deck level blocking the mast should be fine in the transverse direction. In the longitudenal direction you will have problems. The fore and aft lowers will not just attach at a smaller percentage of mast height but actually lower on the mast. A foreward babystay and a couple of fixed backstays going to the aft lower chainplates from the second spreaders would help significantly. Support at the 3rd spreaders is problematical but probably fine as is or with a removable staysail stay and running backs that are only used in heavy weather.

Even though you will not spending wheelbarrows of money to raise the mast height you will still have to spend buckets.

There is a different option to getting more sail area and decreasing the percentage size of the genoa/jib. That would be to lengthen the boom and to add a bowsprit. It looks like you could add 3' or 4' to the boom, which means that you should add a same length or slightly smaller sprit. If I were going to do this I would have a vertical plate running top and bottom along the outer 18"-24" of the sprit with holes for Headstay, Bobstay and tack shackle drilled every 2"-4". This way the helm balance could be adjusted by moving the forestay foreward or aft in increments until the correct position is found. A secondary effect of this is you might also be able to move the shroud bases out to the deck edge without affecting the jib sheeting angles. This decreases the shroud compressive load in the mast by increasing shroud angles and it gets the shrouds out of the middle of the side decks, an unhappy place for them to be when trying to go foreward in rough conditions. The mainsheet track will probably have to move aft into the cockpit.

You would probably be spending small buckets of money for this option.
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