Mainsheet traveler and jib fairlead positions

Can someone point me to some useful books/websites/or salty tricks that can explain when to let out the mainsheet vs move the traveler? Also, how to adjust the jib blocks for a little bit of extra trim? I understand the basic concepts but when you’re out on the water it is never as easy. It’ll add to my list of “boat porn” bedtime reading as my wife refers to it...

juice

I'll give it a shot. Gonna be wordy and there's opinion in it:

The traveler is for sailing close to the wind. On a reach it's no longer a factor.

The traveler controls twist. Twist is the angle of the top batten to the boom. A sail with little twist is flat and fast but easily loses attached flow. More twist is used in sloppy or wave or gusty conditions, because it is more forgiving (the air molecules aren't asked to bend so much, and stay attached longer).

Twist is induced by the mainsheet. Wherever the traveler car is positioned, tightening the sheet draws the leech of the sail down to it. Loosening it relieves the leech. The changes are most easily seen in the top batten. Zero twist puts the top batten almost on zero angle to the boom. As twist is reduced, the top batten trails off, allowing wind to spill from the top of the mainsail.

Without a traveler, twist is hard to control. Consider a main sheet fixed at mid point. Let out the sheet, the boom always rises to max twist.

So, traveler and sheet work together to control twist while sailing uphill (downhill the boom vang takes on the job).

The traveler also allows the angle of the boom to be set as desired.

On a racing boat, the mainsheet trimmer is continually monitoring and adjusting twist. Some mainsheet systems have two "speeds", for finer control of twist. Twist may be taken out when entering a flat spot and more twist put in when penetrating a wake. On a big serious boat with millionaire owner it's a nerve- wracking job. On our boats such close attention is mostly a waste of time.

Essentially, if conditions are difficult, put in lots of twist so the mainsail doesn't stall (lose attached flow).

If the helmsman feels like paying attention on an easy day, bring the top batten in almost parallel to the course, and if pointing to the max bring the boom onto centerline of the boat. You will achieve maximum windward performance for about five minutes, until some distraction occurs and the boat seems to stop dead. The penalty for ambition is severe: Once attached flow is lost, it takes time to regain. We have stalled the wing, and when that happens in an airplane the airplane falls to earth. Twist and a compromise boom position keep a sailboat going, just as maintaining airspeed does for an aircraft.

When sailing to windward, many of us use the traveler to dump the mainsail in a gust. It preserves the twist setting.

Me? I set a course to windward with ample twist and never center the boom. I place the traveler car such that the heel angle is right. If the wind rises I lower the car. The next step is the first reef.

In effect, I set the boat up with traveler position and ample twist, then sail it. All I care about is maintaining the desired angle of heel. In a gust, I feather up. If a big wave appears ahead, I bear off to preserve momentum through it. It is useful to note that 12-Meter America's Cup boats frequently had too much sail for conditions: the boats were sailed feathered almost all the time.

Getting to know the relation of sheet to twist and car to heel is important and fun, but shouldn;t enslave us. That's what racing is for.

Jib blocks: position where a line from midpoint of the luff through clew to deck projects. Change position for downwind. Roller-furling high-clew jibs are forgiving. Decksweepers require more attention to jib car position as their area changes.

If the top of the jib is flapping, move the car forward. If the foot is flopping around, move the block aft.

Ericsons have a rail track and an inner track. The inner track permits close sheeting of the jib to windward. Move the block to the outer track for downwind.

907Juice said:

Can someone point me to some useful books/websites/or salty tricks that can explain when to let out the mainsheet vs move the traveler? Also, how to adjust the jib blocks for a little bit of extra trim? I understand the basic concepts but when you’re out on the water it is never as easy. It’ll add to my list of “boat porn” bedtime reading as my wife refers to it...

juice

Click to expand...

Would recommend Capt. John's Skipper tips. Both the short youtube vids and his site(some content you need to pay for, but it's worth it). And of course, nothing beats a few hrs with a good instructor.

If you want some deep technical jargon, vectors and other esoteric stuff you can't beat Stuart H. Walker's A Manual of Sail Trim. I used to read it before every race and after every race to try to understand what I was seeing and doing wrong. In the early days I'd just pick one sail control and really concentrate on that. Slowly the whole picture builds itself.

Christian's description above, as usual, is pretty dang good. I'd put money he raced against Stuart back in the day.

Chris

Dr. Walker's stuff is very thorough, but... not a light read.

I'd recommend starting with something like the North Sails "fast course". It's a primer on sail-trim (among other things) and provides a very good framework for looking at and adjusting things in a step-wise fashion. Great place to start.

Not sure if they still produce it, but there are copies available on Amazon.

https://www.amazon.com/North-U-Crui...=1513880415&sr=1-4&keywords=north+fast+course

For me, my approach is sort of a "loop" - meaning that I look at the trim, make an adjustment, and then go back and look at it again because each adjustment affects the others.

In broad terms, I think of things in terms of "shape", "trim" and "feel"

"Shape" is the airfoil formed by the sail. the sail may be "flat" or "full", it may be adjusted to move the deepest part of the shape, and it may have "twist" along the back edge.

The shape of the jib is controlled by the headstay, the halyard and the lead position
- a soft headstay tends to make the sail fuller (more powerful), tightening the headstay flattens the sail
- a tight halyard moves the draft forward, softer halyard allows the draft to move back
- moving the jib lead forward "closes" the back of the sail, moving the lead aft lets the top part "open" or "twist"

Similarly, the shape of the main is controlled by mast-bend, outhaul, main halyard, mainsheet-and-traveller-and-vang
-- a straight mast tends to make the sail fuller, tightening the backstay (bending the mast) flattens the sail
-- a tight halyard moves the draft forward, soft halyard allows the draft to move back
-- a tight outhaul makes the sail flatter (mostly near the bottom of the sail)
-- and then mainsheet-and-traveller or mainsheet-and-vang affect twist: tight vang (or tight mainsheet) "closes" the back of the sail, soft vang or mainsheet allow the leech to "open" or "twist"

For the purposes of "shape", think of how they affect the boom. Tightening the vang (or the mainsheet) pull the boom down, which causes the back of the sail to close. Easing the vang (or the mainsheet) allow the boom to rise, changing the shape of the back edge of the sail.

"in general", the shape of the sail should match the conditions. In light air (going upwind) you want smooth, efficient airfoil shapes. If you have telltales on your sails, they're your best indicators. A set of telltales about 1/3 of the way back from the front of the jib will tell you if your jib-leads are right fore-and-aft. They should all be streaming, and if they all "break" or flutter the same, you're good. If the top one breaks before the others, the top of the sail is twisted off too much, and you should move the lead forward a little. If the bottom one breaks before the others, try moving the lead aft a little.

Similarly for the main....telltales on the back edge should all be streaming. if the top one "hides" behind the sail, it usually means the leech is too closed, try easing the vang and/or mainsheet to let the leech twist off a little.

As the wind comes up, you generally want to flatten the shape of the sails, allow the tops to twist off a little to reduce power, and ease the sails out a little to help the boat stay on her feet. Heeling over a lot is not fast - it is far more efficient to de-power the sails (either by flattening them, letting them twist off, or reducing the area) and keep the boat upright.

IMO, once I have the shape where I want it, then I focus on trim - the angle of the airfoil to the wind. For the jib, that means trimming or easing the sheets. For the main, that means using the vang-and-mainsheet or traveler-and-mainsheet to trim or ease. Generally speaking, the traveler is good for controlling "trim" when headed upwind, and as the sails are eased on a reach or a run it becomes less useful, and the vang is used to keep the sail shaped the way you want.

So, back to your original question.... mainsheet and traveller can work together to affect shape as well as trim. If you use the mainsheet to adjust the shape of the mainsail so that it has the right "twist" for the conditions, you can then move the traveler to trim that sail in or out without affecting the shape. And pay attention to how the boat feels - if it is heeling a lot, or feels overpowered, that means it is time to adjust shape (flatten, twist) and trim (ease)


$.02
Bruce

My 2 Cents

I like my Main Sheet at the aft end of the Boom... and the Traveler at the Back of Cockpit... It a fords the most control over your sail... while keeping it out of the way.

I have had a mid boom sheets which are shorter yet must be stronger.

907Juice said:

Can someone point me to some useful books/websites/or salty tricks that can explain when to let out the mainsheet vs move the traveler? Also, how to adjust the jib blocks for a little bit of extra trim?

juice

Click to expand...

RYA Sail Trim Handbook - for crusing sailors, by Rob Gibson. Terrific and easy to understand with lots of illustrations.

And this... http://opcyc.org/main/sites/default/files/Sail Trim_0.pdf

Good stuff, always worthy of review and spirited conversation, thanks for asking.

Bruce, I just picked up a copy of the North Sails Fast Course on Amazon. They had 4-5 used copies avbl for $15-17. Thanks for the recommendation.

We bought a a couple books that are pretty short as refresher courses on main and jib trim. They are by Felix Marks and are on Amazon. Mainsail Trimming and Jib Trimming. As we've brought on new racing crew to the various boats we've raced on, we've loaned out these books to them to help them understand the basics better. Small enough books to not be overwhelming, and cheap enough if they walk off, I don't feel too bad about buying another copy.

I've also been pretty happy with these short little articles from Quantum that pop into my Facebook feed from time to time. They also have them on their website.

https://www.quantumsails.com/en/resources-and-expertise/articles/what-do-i-do-with-my-traveler

https://www.quantumsails.com/en/resources-and-expertise/articles/demystifying-jib-trim

https://www.quantumsails.com/en/resources-and-expertise/articles/how-does-sail-twist-work

Main website for additional articles: https://www.quantumsails.com/en/resources-and-expertise/category/tips-tricks

I have no affiliation with Quantum, don't even own one of their sails, but like the articles... and the YouTube videos of the TP series racing.

Thanks everyone for the great info and links. I've been messing around with my traveler lately, it really helps keep me upright in these winter winds. One mistake I've made is forgetting to release tension off the topping lift fully.... note to self, none of these tips work with tension on the topping lift!

So, Joyride, does the boat tack now?

Yes I've got her tacking now Christian. Growth on the keel caused the problem. 4 large sea anemone. Like speed brakes left on all the time. As she lost lift through the tack the rudder would loose effectiveness. Just like trying to tack without enough speed. Also leaving the outboard down acts like a rudder with a longer moment arm than the main rudder. Handy if my tiller breaks but undesirable for sailing. The outboard lift springs are shot so I was breaking my back putting the motor up and down. I had an Ahha moment - my boom jack has quick release shackles - I use the boom jack to lift the motor (attached to motor and stern) then return it to the boom. Takes 30 seconds. Not the best solution but cost effective and no more complaints to my wife about a sore back after sailing!

I am getting my Ericson figured out and I really like her! The boat I was sailing the last few years was a C & C 24. Very tender compared to Joyride. I missed that at first but now enjoy the stability Joyride has.

As this thread is about travellers and jib block position I'll say I didn't have a traveller or fairlead tracks on the C & C. I am happy to have them now. . The traveller is stern mounted. My fairlead tracks provide great foresail trim AND a sourse of fresh water to flush my bildge when it rains ha ha.

Wonderful!

Wow!!!

I just read all the comments a couple times and i def need to chew on it a few times. Thanks guys and merry Christmas!