Sailors Don't Know How to Set Sails ?

[Ex-Calif]

Originally Posted by foolishsailor

Couple of tips for upwind...

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My quick brain dump – hope it helps someone…

Excellent summary. Recommend printing this out laminating and keeping on board.

When crewed communication is critical. The main trimmer can't usually tell what is happening with weather helm and boat balance although a good one anticipates based on experience. The helm and main trimmer need to talk a fair bit.

Again, for a cruise constant adjusting is a bit more work than most want. Set the right amount of sail for conditions, trim the sails and follow the wind shifts to avoid constant sail trim.

[barnakiel]

Next time on a beach with beach boats rental, anybody with sail trim issues should get a bunch of fellows and go beach boat racing round the anchorage. You will immediately experience things. The one that is worst trimmed comes last.

This is one of the benefits of starting sailing at the small end - one learns boat and sail trim because they are then the major factor in where we get, how we get there, and who buys the beer.

b.

[Dreaming Yachtsman]

Foolishsailor's treatise on sail trim is spot on.

"Cliff notes" version for those of us who don't have their sails covered with tell tales: for a given course off the wind, ease the sails until they just start to luff then bring them back in just a bit. When beating to windward with sails trimmed in all the way, come up until the sails just start to luff then fall off a few degrees.

In practice while cruising, I trim the sails at the beginning of the trip, check them a half our or so later, and after that as conditions change. I'm too old to constantly tweak like I did when racing!

[senormechanico]

Originally Posted by Dockhead

My sails have kind of curved metal cleats with teeth that take the leech lines. If you pull down on the leech line, the cleat takes up the slack and holds it tighter. If you pull out on the leech line, it releases all the tension and you can start over again.

I rarely need any leech line tension. I would rather have a little gentle flutter in the leech, than mess up the shape of the leech with that ugly curl. If the flutter is more than gentle, it is usually a sign of a different problem, in my experience, not usually solvable with a leech line.

A friend and I once went daysailing on a boat owned by another aquaintence who was extolling the virtues of his new to him old IOR raceboat.
(He bought it because it had a ton of stainless winches)

It was blowing pretty good that day 25 knots or so, and the owner was afraid to go to weather, so we did a beam reach. The weather helm was awful.
My arms ached after only 20 minutes, so my friend and I had to keep trading off on the helm. The owner thought that was normal !

The leeches of both the headsail and main were fluttering so badly, it sounded like a helicopter was directly overhead!
When we mentioned the weather helm, the owner looked at us like we were nuts, and when we mentioned the lack of leech lines, he said that just proved we were going fast. Nothing could be wrong with the boat as he had bought it. In his mind it was a perfect and very fast boat, and we were idiots. We did 9 to ten knots in nearly 30 knots on a reach, and our ears hurt !

EWKAAAY ....

All we could do was look at each other and roll eyes.

[Ex-Calif]

Originally Posted by senormechanico

A friend and I once went daysailing on a boat owned by another aquaintence who was extolling the virtues of his new to him old IOR raceboat.
(He bought it because it had a ton of stainless winches)

It was blowing pretty good that day 25 knots or so, and the owner was afraid to go to weather, so we did a beam reach. The weather helm was awful.
My arms ached after only 20 minutes, so my friend and I had to keep trading off on the helm. The owner thought that was normal !

The leeches of both the headsail and main were fluttering so badly, it sounded like a helicopter was directly overhead!
When we mentioned the weather helm, the owner looked at us like we were nuts, and when we mentioned the lack of leech lines, he said that just proved we were going fast. Nothing could be wrong with the boat as he had bought it. In his mind it was a perfect and very fast boat, and we were idiots. We did 9 to ten knots in nearly 30 knots on a reach, and our ears hurt !

EWKAAAY ....

All we could do was look at each other and roll eyes.

There is a lot going on in an IOR boat with three up in 30 knots. Number one is lack of 5 folks on the rail, number two is probably an assured need to short both the main and the headsail.

With full sail up you had to be 15knots overpowered.

[Surfer Girl]

Ex-Calif & S/V Jedi,

You guys are sounding a little bit smug there - not a good look. The title of the thread is "Sailors don't know how to set sails?" (and not "The theory of Hydrodynamics....")

The operative words are 'Sailors' & 'Sails' - both of these are adjustable and/or inter-changeable.
The effect of the keel, dagger board, centre board and rudder on (upwind) sailing performance of a certain sailing craft, although very important, is fixed and non -adjustable (except for hi-tech canting keels). This falls to the naval architect who designed the vessel in the first place; hopefully they got the hydrodynamics right! It either works efficiently in a variety of sailing conditions and points of sail or not. Not much can be done about that unless you have lots of moolah...

FoolishSailor, great synopsis of Sail Trim guidelines!

[s/v Jedi]

Originally Posted by Surfer Girl

Ex-Calif & S/V Jedi,

You guys are sounding a little bit smug there - not a good look. The title of the thread is "Sailors don't know how to set sails?" (and not "The theory of Hydrodynamics....")

The operative words are 'Sailors' & 'Sails' - both of these are adjustable and/or inter-changeable.
The effect of the keel, dagger board, centre board and rudder on (upwind) sailing performance of a certain sailing craft, although very important, is fixed and non -adjustable (except for hi-tech canting keels).

I sure hope your rudder is adjustable

What we talk about is lift generated that interacts with the sails to go forward to windward. Without these fins, it just won't work... which means that explanations done in this thread were just wrong. I don't think that it is looking bad to try to explain that. The smug way is because of the way in which experts put forward wrong info.

I bet that nobody really cares as you say. But please don't say we're not sailors when discussing hydrodynamics because every sailor that wins regattas knows this even better than we do here on CF. Sometimes knowledge and science are good

ciao!
Nick.

[AquatiCat]

Aww, shucks, FoolishSailor, you done posted a much better summary than I could come up with, especially at this time of the evening! I think I'll go laminate that right now...!

[sailorboy1]

this is why sometimes, OK most times, I just like to sail along and not think too much about the whole thing

[Surfer Girl]

Originally Posted by s/v Jedi

I sure hope your rudder is adjustable

I hope so too!



But please don't say we're not sailors when discussing hydrodynamics

ciao!
Nick.

Nick, I would never suggest you're not a sailor!

The way to get the hydrofoils (fins) working well to windward (if the naval architect got their sums right) is through sail trim!
For example, excessive heel which will induce all manner of inefficiencies in the keel and might cause the rudder to stall, is corrected by sail trim, reefing and helm input, not the other way around.

As I said on a previous post, technical explanations will loose most people anyway. Demystifying the jargon & theory and breaking things down is always where to start - and well done FoolishSailor for doing that! If a person really gets into it, they can always grab the text books and get into the science...

[boatman61]

Jeez... aint half glad I'm just a seaman... this stuffs to complicated...
45* to the wind and wobble off...

[dandrews]

Originally Posted by Don Lucas

this is why sometimes, OK most times, I just like to sail along and not think too much about the whole thing

LOL...now this is how a real sailor sails. Thumb!

[Coops]

Originally Posted by Surfer Girl

As I said on a previous post, technical explanations will loose most people anyway. Demystifying the jargon & theory and breaking things down is always where to start - and well done FoolishSailor for doing that! If a person really gets into it, they can always grab the text books and get into the science...

Totally agree, i have tried various times in my 62 years to read the theory books but i just get lost/bored with all the complicating of issues when they write this stuff. Thankyou, in a big way, to Foolish sailor for his great post, but please good sir, now do one for Off The Wind sailing, written the same way.
Also agree with the lazy style cruiser's attitudes, near enough is good enough most times, but i would still like to know, before i finish this life, how what i love really works. I may never put it into practice but i feel less of a sailor for not knowing. Does not make me enjoy it less, just that little niggle that i should know everything, after all, i pretend that i do.

Coops.

[cwyckham]

Originally Posted by s/v Jedi

Exactly. I forced myself to shut up when the forward vector was said to be the result of sail drive and drag only. Lift of keel and rudder is little understood. There's plenty of sources that explain it on-line I guess, but they don't seemvery popular

ciao!
Nick.

Now why the heck would you guys be biting your tongues? How is anybody supposed to learn anything if you guys are sitting back and rolling your eyes? (Sorry, this post came across a bit condescending, I'm sure it wasn't meant that way).

The keel is an oft forgotten part of the equation, but it isn't, in my estimation, a key contributer to weather healm. It's too close to the center of mass of the boat, so the torques are too small.

Anyhow, I think you guys are suggesting that there is no forward drive from the sails, that it all comes from under the boat. I beg to differ. Lift on the keel is important, in counteracting leeway, but I don't think that it is the major contributer of drive (if it does at all). Page 41 of Ross Garrett's amazing "Symmetry of Sailing" shows a diagram of the total sail force compared to the total hull force (sum both the keel forces and hull drag) for a close hauled boat. They are, of course, equal and opposite since the boat is at steady state. The sail force is forward and to leeward. The hull force is aft and to windward.

A boat will sail upwind without a keel, but the leeway is so ridiculous, nobody would want to. The keel is there to get rid of the leeway by using hydrodynamic lift.

[cwyckham]

Originally Posted by Coops

Totally agree, i have tried various times in my 62 years to read the theory books but i just get lost/bored with all the complicating of issues when they write this stuff. Thankyou, in a big way, to Foolish sailor for his great post, but please good sir, now do one for Off The Wind sailing, written the same way.
Also agree with the lazy style cruiser's attitudes, near enough is good enough most times, but i would still like to know, before i finish this life, how what i love really works. I may never put it into practice but i feel less of a sailor for not knowing. Does not make me enjoy it less, just that little niggle that i should know everything, after all, i pretend that i do.

Coops.

If you're interested in the theory, the absolutely most accessible book I've found is "The Symmetry of Sailing" by Ross Garrett. It's accessible and correct. A combination that can be hard to find.