two main sheets

[tugz]

going to be sailing a 40' cat with twin main sheets, whats the right way? both tight all the time, windward side slack??

[44'cruisingcat]

Depends on the point of sail. To windward you'd have both sheets in use, DDW usually only one. Although the other sheet might be relocated and used as a preventer.

[Factor]

you have two sheets and no traveller, you need to use both sheets to control sail shape.

[Franziska]

More tension on the leeward sheet pulls the sail down and flattens it.
Closes the top of the sail in the same moment.

Putting less tension on the leeward sheet introduces more twist in the sail and dumps some power high up.

Play both sheets.

When going to windward you could keep both sheets tight and center the boom so you do not need to attend to the main in a tack.
Pending on the boat you might keep the old jibsheet tight until she is through the tack completely.
Sometimes you might need to loosen the mainsheet in the tack if you have issues going through the tack.

Have fun!

www.ladyrover.jimdo.com

[multihullsailor6]

When going downwind or broad reaching make sure the leeward sheet, which on this point of sail is normally unloaded, is secured as short as possible in the cleat to act as an anti-gybe stopper.

[2Hulls]

Originally Posted by multihullsailor6

When going downwind or broad reaching make sure the leeward sheet, which on this point of sail is normally unloaded, is secured as short as possible in the cleat to act as an anti-gybe stopper.

That may be accurate on some boats, but not others. Depends on how far outboard the sheets are anchored and whether there's an alternate, outboard anchor point specifically for use as a preventer function.

tugz - what model boat are you chartering?

In general, you can place the boom where ever you want it, so visualize where you want the boom as if you had a traveler and maneuver it there using the two sheets. Then work the sheets to get the leech tension/twist in the mainsail for the conditions.

An additional capability not as easily used with a traveler system is using the topping lift as a third anchor point in light conditions to hold the boom steady against the sheets to keep the boom from pumping up and down with the variations in wind speed and movement of the boat in the chop/swell. You can lock the boom in place using the sheets and topping lift to maintain the sail shape you want. This takes the weight of the boom out of the mix.

Dual main sheets is a fabulous setup for wide beam multis. I'm amazed more cruising cat designers don't employ it. Using travelers is sooooo monohull.....

Dave

[tugz]

Thank you all.
it's a new Leopard 40