What's faster, questions on balance while cruising long distance

[sailorladd]

I failed to mention that I built my boat that was designed to be a bilge keeler (New Zealand designer Richard Hartley) I found her to be too sensitive and not enough lateral resistance to point high... I removed the bilge keels and extended her keel deeper and added a lot of extra ballast, her new rudder was built larger and attached to the aft of the keel again... this was in Cape Town around 1981, I have since cruised her virtually around the world and currently reside in Hawaii... I have never experienced heavy helm since that rebuild...check out the book I wrote ...

[nofacey]

Aft mast rake worsens weather helm, as does excessive mast bend. Stand the mast up, put just enough bend in to have main set nice

[donradcliffe]

Glad you figured out that the last change caused the problem.

[sailingharry]

A lot of good answers, and you think you've "solved" it. But a few comments:
* Spinning/locked prop -- I almost contributed to propogation of bad guidance, but read this very good article (data by MaineSail) and learned I was wrong: https://www.catamaransite.com/refere...ler_drag_test/

* Vang/traveller. A traveller is a wonderful tool, until the boom is outside the end of the traveller. Soon, the only downward force (sail shape force) on the boom is the vang. On a reach, the traveller is useless.
* Sail shape. As commented, a tight vang is ideal sail shape, but the enemy of your issue. The vang keeps the entire main full and driving. On race boats, with a spin up, a crew is kept at the vang with directions to dump it if the boat starts to round up -- this depowers the main and lets the helmsman get the boat back off the wind (exactly what you are wanting).
* Center of Effort/balance. Upwind, this is gold. Offwind, not so much. I find that heel-induced weather helm is far more powerful than sail balance. Beam/broad reach, jib alone with no main is fine. In a cutter, that would be the outside sail, not the inside -- get that COE forward! I even find that on my boat, upwind in heavy air, a 95% headsail and no main at all is a wonderful sail combination, making hull speed and tacking through 90 degrees with next to no helm -- when you would expect significant lee helm.

[s/v Jedi]

Lots of information but sometimes incomplete, out of context or even wrong.

About the traveler: this obviously attaches the sheet to the hull. So the more forward the traveler is located, the less weather helm?

Also, the easiest way to move the traveler forward is to attach the sheet halfway the boom instead of at the end. This has the same effect as making the traveler twice as wide. For example, on a beam reach we have the sheet tight and the sail angle is done with the traveler.

About sail twist: sail twist primary function is to trim the sail. You use tell tales to verify flow over the sail and add or reduce twist to get it right from top to bottom.
Using sail twist to de-power the top of the sail is a trick, only to be used to prepare for reefing. As soon as the (extra) reef is set, twist should be adjusted for sail trim again.

Keep in mind: weather helm #1 cause is heeling. Reducing heel is the most effective method to reduce weather helm. But you always want some weather helm. During a beam reach, the boat should slowly round up when you let the helm go free. A rudder angle indicator is a great tool because once you have found the right trim for your boat, you can note the rudder angle and use that during future trimming.

[SY Maara]

Another thing to try that most forget is twist off the main in reaching conditions like that as it keeps the drive low down
Pull the traveller right up and easy the mainsheet, this lets the head fall open but keeps the drive down where it’s most useful
I’d probably not use the staysail either in these conditions as it maybe stealing power from your genoa, but as the wind increases you may loose the granola and go back to the staysail
Experiment lots, you will have the time crossing, depending on the rig one reef and twist maybe the most comfortable, most of your speed comes from low down power

[sailingharry]

Originally Posted by s/v Jedi

About the traveler: this obviously attaches the sheet to the hull. So the more forward the traveler is located, the less weather helm?

So in general I mostly agree with you, and sometimes I agree to disagree. But in this case, no. This is flat wrong.

I know you are a rather technical person, but not sure if you are an actual engineer. I am.

This is a basic free body diagram. The center of load on the sail is fixed by the center of the sail (usually shown on the sail plan) and applies in the same vertical line on the hull (since we are talking about weather helm, not heeling, we are basically looking at this as a 1-dimensional problem -X- without consideration of the Y axis). Assuming a static situation ("statics" vs "dynamics" -- two of the first courses we take), the actual mechanics of the connection don't matter (dynamics includes inertia and such -- even with a sailboat under way, it's still a "static" situation). Think about the same boat sold with both an aft and mid-boom traveler -- the sails are the same and the performance is generally the same -- the boat doesn't suddenly lose weather helm when the sheet goes forward.

What actually happens is that "the sum of the moments is equal to zero." As the sheet moves forward, the corresponding force pushing the mast to leeward drops until the sheet is at the line of the center of effort where it balances on the sheet, and then the force on the mast starts pushing to weather.

[s/v Jedi]

Originally Posted by sailingharry

So in general I mostly agree with you, and sometimes I agree to disagree. But in this case, no. This is flat wrong.

I know you are a rather technical person, but not sure if you are an actual engineer. I am.

This is a basic free body diagram. The center of load on the sail is fixed by the center of the sail (usually shown on the sail plan) and applies in the same vertical line on the hull (since we are talking about weather helm, not heeling, we are basically looking at this as a 1-dimensional problem -X- without consideration of the Y axis). Assuming a static situation ("statics" vs "dynamics" -- two of the first courses we take), the actual mechanics of the connection don't matter (dynamics includes inertia and such -- even with a sailboat under way, it's still a "static" situation). Think about the same boat sold with both an aft and mid-boom traveler -- the sails are the same and the performance is generally the same -- the boat doesn't suddenly lose weather helm when the sheet goes forward.

What actually happens is that "the sum of the moments is equal to zero." As the sheet moves forward, the corresponding force pushing the mast to leeward drops until the sheet is at the line of the center of effort where it balances on the sheet, and then the force on the mast starts pushing to weather.

You could just say the sheet attached mid boom gets a proportional higher load You really question if I am an egineer? How dare you! haha

[sailingharry]

Originally Posted by s/v Jedi

You could just say the sheet attached mid boom gets a proportional higher load You really question if I am an egineer? How dare you! haha

I don't question your skills! But many with really good skills got them ways besides college. And some with a degree....nevermind.... I seriously don't know (or care!) if you have an actual engineering degree. Here on the water, it's what you can do that matters. On the job front, somehow, it's the paper that matters.....LOL.

[s/v Jedi]

Originally Posted by sailingharry

I don't question your skills! But many with really good skills got them ways besides college. And some with a degree....nevermind.... I seriously don't know (or care!) if you have an actual engineering degree. Here on the water, it's what you can do that matters. On the job front, somehow, it's the paper that matters.....LOL.

Well, none of my degrees are of mechanical or nautical engineering (I am a retired electronics, IT and computer network engineer) but I try to improve on all aspects of engineering incl. even diesel mechanical etc.

So this also means that when we bend the mast, we transfer load from the mast to the sheet?

[sailingharry]

Originally Posted by s/v Jedi

Well, none of my degrees are of mechanical or nautical engineering (I am a retired electronics, IT and computer network engineer) but I try to improve on all aspects of engineering incl. even diesel mechanical etc.

So this also means that when we bend the mast, we transfer load from the mast to the sheet?

I had the strong feeling your technical skills were more in the IT arena. My grandson is in HS, and he keeps waffling between "I want to be an engineer" and "I like computers." Many of the same brain tendencies.


Not sure about what you mean regarding bending the mast.

[s/v Jedi]

Originally Posted by sailingharry

I had the strong feeling your technical skills were more in the IT arena. My grandson is in HS, and he keeps waffling between "I want to be an engineer" and "I like computers." Many of the same brain tendencies.

Not sure about what you mean regarding bending the mast.

Well, mast bend is a regular form of trim. I use masthead running backstays for it.

[sailingharry]

Originally Posted by s/v Jedi

Well, mast bend is a regular form of trim. I use masthead running backstays for it.

For most cases, the main (and its sheet) don't bend the mast much (small boats with significant fractional rigs and bendy masts are an exception). The force on the sheet is almost 100% the result of wind forces. Take a sail well trimmed for upwind work in 10kts, and get a lull -- the sheet goes nearly slack.


But don't ask me about mast bend! On my Lightning (fractional rig dinghy) I fully understood it. On my current boat, with a masthead rig and inline shrouds, I don't understand it at all. I don't even understand why it does what I see it doing! Let alone how to make it do what I WANT it to do!

[thomm225]

It's always a balance between all the variables.

You can lose a race with incorrect sheeting for example. Not to mention mast prebend, batten tension, mast rake, sail selection, downhaul tension, starting position, etc., etc.,

Asking cruising sailors about what makes a boat go fast is a waste of time since most have never raced especially one design side by side with 10-30 other boats of the exact same type.

It's easy to say do this or that until you line up and race.

Then you learn what's fast and what is slow.

[Greatest Lakes]

The original question asked what is faster for cruising long distance. This was followed with questions to the amount of acceptable weather helm. When I was little, one of the first things I was taught was that the rudder is a brake, the more you need to use, the more energy you are wasting. It's also a bit more wear and tear on the boat, not that it can't handle it, but it probably shouldn't have to. Reefing the main and balancing your rig in higher winds makes for a smoother ride, better control and possibly higher speeds. Heeling past 20 degrees in most boats is fun, but that's where your rudder, if a single, starts to become less effective. A more upright rig helps too.