Placing tracks for a staysail

[Dockhead]

Originally Posted by Paul L

I'd start by extending the LP line of the sail to the side deck and center the track around it.

The reason why this is correct is that if you pull the clew at this angle, the tension will be equal on foot and leech for uniform shape of the sail.


I heartily second Tillsbury's suggestions to use twings instead of tracks. Much easier to install, much less to trip on, and potentially much better control. Also much cheaper.



One set of tackle per side duplicates the function of a track; but with two sets of tackle per side, you actually have 3D control of the clew placement. Or, a single barber hauler connected to both port and starboard twings will adjust the clew inboard and outboard -- that's what I have. Headsails respond dramatically to small inboard-outboard adjustments of clew position, so this is a really valuable control.



I have been living with this system for my blade jib for about 5 years now and love it.

[Tillsbury]

And remember the inboard ends can be the same point. Could be the babystay mount or the mast step, giving you two of the attachment points for nothing!

[Dockhead]

Originally Posted by Tillsbury

And remember the inboard ends can be the same point. Could be the babystay mount or the mast step, giving you two of the attachment points for nothing!

Not only a single point, you can use a single line to tweak both twings inboard.

[GILow]

Originally Posted by Tillsbury

And remember the inboard ends can be the same point. Could be the babystay mount or the mast step, giving you two of the attachment points for nothing!

Originally Posted by Dockhead

Not only a single point, you can use a single line to tweak both twings inboard.

Guys, great advice, and good to have it here for people searching, but in my case running the lines aft really is a nightmare, so I will have to stick to the track option, even though I concede it may be sub-optimal.

Still trying to reconcile waterman46 and Jim Cate's contradictory advice.

[Tillsbury]

Originally Posted by Dockhead

Not only a single point, you can use a single line to tweak both twings inboard.

Good plan DH! And couldn't you also have a single line running the same way to a block, splitting off to the toerail on each side for the outhaul? Only two lines in the cockpit, and both tacks adjusted to the same setting automatically....

[Shala]

I heartily second Tillsbury's suggestions to use twings instead of tracks. Much easier to install, much less to trip on, and potentially much better control. Also much cheaper.



One set of tackle per side duplicates the function of a track; but with two sets of tackle per side, you actually have 3D control of the clew placement. Or, a single barber hauler connected to both port and starboard twings will adjust the clew inboard and outboard -- that's what I have. Headsails respond dramatically to small inboard-outboard adjustments of clew position, so this is a really valuable control.

hey guys
im also trying to configure some way of controlling the staysail...i am having a bit of trouble trying to visualize this configuration...anyone able to draw a simple picture to explain it better. yes i am a little mentally challenged (hehehe) and pictures help me alot.
thanks

[Tillsbury]

Originally Posted by Shala

hey guys
im also trying to configure some way of controlling the staysail...i am having a bit of trouble trying to visualize this configuration...anyone able to draw a simple picture to explain it better. yes i am a little mentally challenged (hehehe) and pictures help me alot.
thanks

Here's an example. The red sheet comes from the sail through the ring to the winch. The lower red line is the outhaul which runs from the deck, through the ring, down through another ring attached to the same point, and back to the cockpit, so it's got a 2:1 advantage. The blue line is the inhaul, which does the same thing but mounted inboard.

Pull both the control lines to lower the sheet lead (same as car forward on a track). Release both to raise it (same as car backwards). Pull one or other line to move the sheet lead inboard or outboard.

It's also possible to have these with 3:1 by starting the controls with a splice around the ring itself, which is stronger. But if you have a beefy enough ring you should be ok.

[Shala]

most excellent tillsbury ...that is very helpfull...thanks a million
i guess now i need a couple more winches in the cockpit.... well if it isnt one thing its another...hahaha
thanks again

[Shala]

oh ya ...a couple more questions...
what are the rings made of and what type of line are you using?
thanks

[Tillsbury]

Lots of places make low friction rings. Antal, Rutgerson, Harken, Spinlock... I doubt there's a deck hardware company that doesn't. Plain Dyneema for the control lines, covered at the end if you like. The right mechanical advantage should mean you don't need a winch, just cam cleats.

[Shala]

thanks again tillsbury..
i love mining the knowledge banks.....

[Tillsbury]

Hey, I got it all from here...

[Matt Johnson]

Originally Posted by Shala

most excellent tillsbury ...that is very helpfull...thanks a million
i guess now i need a couple more winches in the cockpit.... well if it isnt one thing its another...hahaha
thanks again

The loads are lighter than you'd anticipate, and you usually don't need to winch them unless adjusting when hard on the wind, high wind speeds, or large boat. Even then, the lines are easily hand adjusted if you set the position before tacking or adjust before heading up.

You'll use Dyneema for the lines since it is both strong and slippery. Just check for chafe often... I was on that Pogo 12.50 in that photo when it blew a 1/4" dyneema inhauler trying to adjust when close hauled... don't do this

Matt

[scherzoja]

Skene's Elements of Yacht Design. Updated by Francis Kinney. 8th Edition. GP Putnam's Sons. 1973

Page 208
"In plan view, come aft at a 10 degree angle from the center line, starting at the jib stay on deck. In profile, take a point 40% up the luff of the jib, and from here through the clew draw a straight line. There the line intersects the 10 degree line on deck will be the spot from which the jib sheet should be led."

Page 209
"Take a point in profile 50% up the luff of the jib and another point at the intersection of the Luff and the perpendicular [LP] from it to the clew. Then from halfway between these two, draw a straight line through the clew to the deck. Some designers use a 12 degree line on deck and even 14 degrees for a Genoa jib. "

See attached pictures. First one (Skene-Method1.jpg) is from the book. The second one (Skene-Method2.jpg) is my drawing and I'm not a good artist, but you'll understand the concept.

[Jim Cate]

the above dicta result in an "optimum" single point for the sheet lead, but of course when one has a track or twings, one is free to adjust things to optimize sail shape for differing conditions and points of sail.

So, for Matt, the 10 degree line might well be a good starting point for his staysail tracks, but that will give a sub-optimal shape for reaching off. And as most any sail trim book will suggest, when reaching the sheet lead should move outboard and forward from the close hauled position... as Matt found in his research.

Jim