Release Outhaul Tension When Not Sailing?

[rardiH36]

After much-too-much time on my garage floor, I finally completed the cut-down and transformation of a too large second hand sail into the perfect (in my dreams!) loose footed main sail for my boat. I installed it today. But because of heavy winds today, I did not give it a real life try. The block and tackle arrangement I have set up gives 15:1 purchase. Allowing for friction losses, a 50lb pull on the control end might result in (say) a real life 10:1 =500lbs of tension along the foot.

First question is: Can I leave the foot fully tensioned between outings? Or is it better practice to release the tension when the boat is at berth?

Second question is: Please suggest websites that give instructions on outhaul tension adjustments vis-à-vis wind velocity, luff tension, etc? My only previous experience is with main sails with slugs attaching the foot to the boom. Due to friction of the slugs, I tended to just give the foot a moderate bit of tension ... and then forget.

 

[Jackdaw]

Always ease tight sail shaping loads when done. Outhaul, jib halyard, etc.

 

[sunman]

ya know sometimes the answer is obvious

 

[thinwater]

I also think you will find that with a loose foot sail, the actual outhaul load without the wind in the sail is generally zero. Unlike halyard load for flattering, you are just taking the curve out. Additionally, if you are using the sail properly, you ease the foot every time you are off the wind, so adjusting should be common place.

 

[Joe]

Draft stripes will help set the outhaul more than anything. You're goal is to keep the air attached to the sail... so a set of leech telltales is invaluable. The draft depth is easily determined with a loose or shelf foot sail; it's very intuitive to adjust... you'll get it right away.

It is unlikely that you'll ever leave the outhaul fully tensioned unless you drop the sail in a gale. It's much like taking the tension out of the leech when you raise and drop the sail... it works easier that way without the load.

I always bring the foot in snug when I drop and flake the sail.. but it's definitely not under tension.

 

[Don Guillette]

rardiH36: Here's a very simplistic explanation of outhaul adjustment. The outhaul controls draft depth. Draft depth is your accelerator. Let's take LA harbor as an example, where the winds are normally very light in the AM and tend to build into the afternoon. You would start out with a flat sail (outhaul tight) because the light wind can't get around a sail with any belly. As the wind starts to pipe up you'd start to induce belly gradually and in time with the wind until you got to 25% draft depth -- unfortunately, DD is measured as a %. After 25% DD, more belly becomes counter productive. As the wind continues to build you'd want to gradually reduce DD, working your way back to a flat (less powerful) sail.

On "set & forget" the outhaul. Most older Catalina's that have the internal outhaul are a case in point. The internal outhaul was a poor design and the system didn't work. The result was the outhaul was frozen in place. The outhaul was like the broken clock - it was right for one point of sail and wind condition and wrong for all others.

Like Joe from San Diego, I don't see any point in keeping the outhaul/halyard completely tight while the boat is docked. Take the tension off the sail. After a hard day sailing, you're sail deserves a rest!!

 

[rardiH36]

Thanks all for the good explanations. I'm excited about getting more efficiency from my sails than my previous slug-footed arrangement.

Seems that adjusting the outhaul frequently is as important as attention given to the jib sheets and the main sheet.

I installed my outhaul purchase tackle so that the control is at the forward end of the boom. But I do have one unused deck organizer sheave. Thinking now that I should modify to lead the outhaul line back to the cockpit. Hope that my already installed line is long enough!

 

[Jackdaw]

Thanks all for the good explanations. I'm excited about getting more efficiency from my sails than my previous slug-footed arrangement.

Seems that adjusting the outhaul frequently is as important as attention given to the jib sheets and the main sheet.

I installed my outhaul purchase tackle so that the control is at the forward end of the boom. But I do have one unused deck organizer sheave. Thinking now that I should modify to lead the outhaul line back to the cockpit. Hope that my already installed line is long enough!

It instructive to remember for maximum sail control and effectiveness, ALL lines need to be watched and adjusted as needed! If it has a line attached to it, it is meant to be ADJUSTED. If it was not meant to be moved, they would have just shackled it in place!

Every boat will be different. It therefore helpful to break them into two groups; BIG lines and SMALL lines. BIG lines are sheets and others that have, well, a big effect on trim. These should be monitored and adjusted accordingly. Lines with less effect are SMALL lines and are checked and adjusted less often; certainly after the BIG lines!

Get in the habit of actively monitoring ALL your BIG lines; and looking after your SMALL lines.

That's work. I know. But as anyone that has sailed with me will tell you, my favorite expression is: SAILING FAST IS A FULL TIME JOB.

 

[rardiH36]

.... It therefore helpful to break them into two groups; BIG lines and SMALL lines. BIG lines are sheets and others that have, well, a big effect on trim. These should be monitored and adjusted accordingly. Lines with less effect are SMALL lines and are checked and adjusted less often; certainly after the BIG lines!

Jackdaw:

Just one detail missing from your great contribution -- which I have read several times. Not adequately defined is whether the outhaul is a BIG line or a SMALL line! (I am expecting its one of the BIG ones ..)

I've got them all on my boat. Jib sheets, jib block fore/aft adjustment, a barberhauler is easily rigged, mainsheet, traveler, halyards, cunningham, backstay tensioner, boomvang, reefing points, and now the outhaul for the loose footed conversion. I know what each one does to sail shape and position relative to the wind.

But despite lots of reading, just never quite got to the stage of intuitively knowing the right sail shape for each point of sail and wind velocity. (This is probably due to taking up sailing late in life. Much like trying to learn a new musical instrument as an adult. One might learn much of the mechanics but will struggle to get as proficient as a person that played the instrument as a child.) Don Guillette's sail trim guide is on my boat. But because I am normally fully engaged dealing with the regular almost gale force winds in SF Bay's "slot", regrettably the guide doesn't come out of my nav station desk very often.

rardi

 

[Stu Jackson]

rardi, what I've learned, for starters, is: "if it looks good, it usually is AND when in doubt, let it out a little."

Don's book is great. I'd take it home & read it.

With your new outhaul, regardless of the size of the line, it is a BIG one in terms of affecting your sail shape, especially now that you have the loose foot.

Run it aft and use it.

 

[Jackdaw]

Jackdaw:

Just one detail missing from your great contribution -- which I have read several times. Not adequately defined is whether the outhaul is a BIG line or a SMALL line! (I am expecting its one of the BIG ones ..)

rardi

Great point! Once you get beyond the sheets and traveler, what is big and what is small becomes kinda boat dependant. But there are 'guidelines'. On a 36 foot masthead cruiser, I would guess that the outhaul is a SMALL line. Its part of your check/sweep, you feel it's setting on the sail, but you don't have the line in your hands. Even actively sailed with a full crew, nobody on a H36 will have the outhaul in their hand. Remember, they ALL get adjusted. Its just a question of what needs constant attention.

A good example on how this works is on our First 36.7. Fractional with a huge main, when we sail in breeze the backstay is played along with the traveler and we often will not touch the sheet! Every boat has its own rules.

 

[Don Guillette]

Every boat (like every woman) is different but each sail trim control for the main and jib performs the same adjustment function for draft depth, draft position, twist and angle of attack. Their function never changes. It's like playing a musical instrument. In fact, I use that analogy in the "introduction" in my book. To reach 100% efficiency, you've got to use all of the sail trim control for the main and jib. It's essential that a mate know which function each sail trim control adjust. If they don't, it's like driving a sports car where you slam it in second gear, floor the accelerator and then pull up the emergancey break. In other words, some of the controls are now working against each other.

I can make it easy for a sailor. i provide a FREE "quick reference" with each sail trim chart. The quick reference tells you which sail trim control for the main and jib adjusts draft depth , draft position, twist and angle of attack and also tells the sailor which way to push or pull the control to get the adjustment they are seeking.

 

[Joe]

If the outhaul control is inconveniently located, you won't use it very much. At the very least, put the cleat near mid boom so it can be reached from the cockpit. If you have a dodger, even that might not work....

 

[rardiH36]

If the outhaul control is inconveniently located, you won't use it very much. At the very least, put the cleat near mid boom so it can be reached from the cockpit. If you have a dodger, even that might not work....

Yep -- I did take note of the convenience aspect as this thread developed and so this afternoon I rigged for back to the cockpit. The control end of line from the 5:1 block and tackle that I put inside the boom turned out to be just long enough (for allowing a reasonable degree of slack) to route through a turning block at the mast base, through the spare deck organizer sheave, and finally through an empty hole in my double rope clutch. Lucked out this time. Not many of my projects go so easy. Futzing with the main's foot tension will now be almost as convenient as my main and jib sheets. Certainly will add another dimension to sailing.

 

[Benny17441]

My best understanding of the function of the outhaul is that it mainly controls draft in the lower 1/3 portion of the sail.

 

[RichH]

Leaving the outhaul tensioned will promote permanent 'stretch' (creep) in the foot of the sail ... any kind of sail - woven dacron, laminate sail, doesnt matter.

Here's how to precisely tension the outhaul (draft) for the day's windstrength and seastate:
• Go onto a close-hauled beat,
• watch the speedo as you adjust in/out on the outhaul. The correct amount of draft/outhaul tension will occur at that outhaul tension that results in maximum boat speed.

This adjustment will automatically compensate the amount of draft between a 'flat shape' for 'speed sailing' in flat water and a 'powered up' shape for 'puncning' through steep waves or heavy chop. This is automatic if you simply set/adjust the outhaul for maximum boatspeed output.
You can always 'power-down' from that optimum, to ease your discomfort (aggressive heeling).

Note: When adjusting the amount of draft in the main, remember that the flow over and 'around' the mainsail (sail / aerodynamic interaction) is what makes the jib/genoa efficient ... so you will also have to adjust/tweak the jib/genoa fairlead and the jib/ slot-open distance to the main when setting up for the day's optimum shape - maximum boat speed.
(All this draft adjustment is AFTER you apply appropriate mainsail halyard tension so to arrive at your desired amount of 'weather helm' so youre not 'dragging' your rudder at an angle - ). ;-)