Changing to square top high roach mainsail

[cousineddy]

I would like to switch to a square top sail to add some efficiency to my underpowered boat. I am concerned about the square top interferring with the back stay. Has anyone upgraded to a square top? What did you do about the backstay...if anything?

[Faster]

What boat? Any boat with a standard fixed backstay is not going to work with a modern 'square head' main. Typically these rigs (on small boats) and going to be swept spreaders and no backstay, or a moderate 'square' head with a backstay whip, though I suspect most such rigs that actually work will rely on running backstays.

Without knowing what boat you're thinking about modifying it's tough to say much more...

[cousineddy]

Its a US 25. It has a smaller J and E than the higher performing boats of that size. So, I have a flammin case of SA/W envy. It may not be worth the trouble, but I was thinking dual running backs, or maybe an upper split backstay with a wishbone mast head. I really think those square tops are sweet....I always thought that the top third of the rig was basically useless.

[Faster]

That's a tough one... you'd definitely need twin runners to run such a sail on that rig. I'd wonder about excessive weather helm too, as a result of moving the center of effort aft with the extra roach in the main. That rig has in-line spreaders, IIRC, so you couldn't afford to forget a runner on a gibe or a tack.

Probably not a practical thing to do, but fun to consider isn't it?

[captbillc]

a square topsail on a yard has two sheets , two braces to swing the yard & a halyard to raise the yard. the minimum lines for a small one. not a practical conversion for this boat.

[cousineddy]

Its not that extreme of a square. I think I just need a bracket that mounts to the masthead and sets the backstay aft about 18 inches. Ill send pics when done.

Will my rating get docked?

[mitiempo]

That is not what he is referring to. He is thinking of a racing type main with a square top held by a batten and a whip for the backstay or runners and no backstay like shown below. Here's a link discussing the problems you can encounter: Fat head, or square top mainsails, in one form or another, have been around for what seems like forever, but have of course come into vogue of late in a fairly broad spectrum of boats. Harry Pattison, of E/P Sailmakers takes a closer look.

[mitiempo]

Originally Posted by cousineddy

Its not that extreme of a square. I think I just need a bracket that mounts to the masthead and sets the backstay aft about 18 inches. Ill send pics when done.

Will my rating get docked?

If I was one of your competitors I would hope so.

[cousineddy]

You can add a full batten high roach sail as long as you dont change standard measurements, right? Thats kinda what this is.

[mitiempo]

I guess that would be up to the PHRF committee.