Spinnaker sheet routing

[jarcher]

Hi All, how do you route your spinnaker sheets? I have a 30 foot boat with spinnaker winches in the cockpit, about a third of the way forward from the stern.

I am thinking that the sheets should go all the way aft, to the very stern, through snatch blocks connected to the toe rail, then forward to the winches?

Thanks...

[olson34]

Best way to look at this is to try the lead from the end of the deck back by the transom, and also at other places going forward.
One our boat the best all 'round lead turns out to be forward several feet, by the winches.

Trim up for a reach and see where the leach breaks.

Initially, put the turning block all the way aft, and then put another block on the sheet as a Barber Hauler and try changing the angle while watching the sail.

It might be different than you think.

Good news if it turns out that you can get a fair lead to the primary further forward with a stout snatch block on the rail nearby. Less of a direction change is less friction.

Best,
L

[Faster]

The general rule of thumb is the turning blocks for the spinn sheets should be approx the SPL aft of the mast (pole length).. you can play with that as Olson describes for the optimum spot - though it can change with wind angle and esp wind strength.

When the wind pipes up moving the leads forward helps stabilize the chute. Twingers do the same job without moving the leads, and are more easily adjustable to the conditions.

If you're using double sheets and guys then the guy leads can be moved forward to max beam, easing the load on the downhaul.

Another decision for you is whether or not to lead the sheets inside or outside the lifelines.. I've found with our current boat (also a relatively narrow transom IOR style) that most cases I can lead the sheets inside the lifelines to minimize the drag and force on the lifelines on most points of sail. How this will work for you depends on the exact positions of lead blocks and how high you tend to carry the kite.

[zz4gta]

Keep in mind where you want weight while going downwind. Starting from the clew the sheet/guy goes through the twings (you have twings right?) then to cheek blocks at the transom corners, then up to turning blocks at the toe rails near the bulkhead, then to the secondary winches.

Twings allow you to change the lead while you're sailing.

[jarcher]

Originally Posted by zz4gta

... (you have twings right?)...

Twings allow you to change the lead while you're sailing.

Twings???

[COOL]

Originally Posted by jarcher

Twings???

Twings are like barber haulers for the spin sheets,
or guys. They generally consist of a snatch block
on a line that runs through a block on the rail forward
and then to a cleat. They allow you to adjust the trim
angle of the sheet.
Since the Max beam diminishes rapidly towards the
stern on a Scampi, you may not want the sheet leads
all the way aft, except pehaps when close reaching.

[zz4gta]

I made my own twings from some spare line and a couple shackles. I have harken ti-lite blocks held to the toe rail by a dyneema loop. The twing line goes from a cleat at the bulkhead to the block on the toe rail and then up to a shackle spliced onto it which clips on to the sheet/guy.

I used some cheap azz shackles b/c snatch blocks are expensive and usually pretty heavy. If the wind goes light, just blow the snap shackle to get the weight off the sheet. If the inside surface of the shackle is smooth, you can probably do the same on a 30 footer. How big is your kite?

[jarcher]

Thanks for explaining, that's a huge help. I have not flown a chute on a boat this big before, just on dignhys. I can see I'll want the shackles light on the chute, and I probably have some lieing around. I have plenty of snatch blocks for the rail. I can easily add some cleats for that.

The Spinnaker is 824 ft^2. Its on order and will be here in 8 weeks. Superkote 60. Its as big as PHRF allows without taking a penality. I think i have to shorten my pole as well, but its a lot easier to shorten it then make it grow.

I'll have to crack open my sail trim books. So far I have been spending all my time worrying about upwind trim!