In mast furling mains - the good, bad and ugly

[Bob Perry]

I'll be 65 in June. Fuck!

That means I have now been sailing for 50 years and I'm still trying to figure it out.

I drew the Valiant 40 when I was 28 years old and knew everything.

Now I wonder.

But I do know a few things.

I know that Pardey main looks like shit.

I know that on an in mast furling Saga 43 I calculated the mainsail area lost over a conventional main to be 40%. That's a lot.

I do know that leach line tension in mains and genoas just adds cup to the leach.

I know that two full top battens and two long, partial lower battens works best for me on my 26'er.

I know my laminated UK sails have proven very durable and I love them.

I know my wife went down this morning to haul the boat and do a bottom job.

So I got that going for me.

I know I'm not the guy to ask to evaluate golf clubs. I don't swing the samne twice.

Over the years I have had the honor of sailing and learning from some great sailors.

I know I don't mean to argue here on CA I just try to pass along the few nuggets of sailing wisdom that have come down to me over the years so that people still, on the steep side of the learning curve can benefit from my efforts and learn a bit quicker.

 

[U20guy2]

I'll be 65 in June. Fuck!

That means I have now been sailing for 50 years and I'm still trying to figure it out.

I drew the Valiant 40 when I was 28 years old and knew everything.

Now I wonder.

But I do know a few things.

I know that Pardey main looks like shit.

I know that on an in mast furling Saga 43 I calculated the mainsail area lost over a conventional main to be 40%. That's a lot.

I do know that leach line tension in mains and genoas just adds cup to the leach.

I know that two full top battens and two long, partial lower battens works best for me on my 26'er.

I know my laminated UK sails have proven very durable and I love them.

I know my wife went down this morning to haul the boat and do a bottom job.

So I got that going for me.

I know I'm not the guy to ask to evaluate golf clubs. I don't swing the samne twice.

Over the years I have had the honor of sailing and learning from some great sailors.

I know I don't mean to argue here on CA I just try to pass along the few nuggets of sailing wisdom that have come down to me over the years so that people still, on the steep side of the learning curve can benefit from my efforts and learn a bit quicker.

Nice!

My wife sails and likes to win but so far I haven't been able to get her to wax the boat or do a bottom job so your doing really well Bob LOL :lol:

 

[U20guy2]

I dont think i would want to be sailing in a small canal, with no room... think boy scout .."be prepared" ahead of time....

Not my first choice either, but if you have a sudden, emergency need for a mainsail, a mast furled one is the only kind that is routinely stored in the "ready" mode. I suppose it's also true of boom furled sails, but those can't be deployed as quickly as a mast furled one, which will blow out like a rf jib does.

We'll OK if you say so but in every case where we needed to move and move fast even when we had sails up already this is how we did it.

Check for lines over the side

Clear

Turn key

Put engine in gear

and motor out of trouble

Takes about 10 seconds if you know the boat.

Yes, but in the incident I was referencing, we had shut down the engine to avoid damage to an overheating dripless shaft seal. We did wind up using it to dock, as I recall.

In another incident, I was leaving Little Harbor, Abaco in an east wind. Check a chart. Shortly after we exited the narrow harbor entrance, the engine died. We managed to set an anchor, which fortunately held. We then managed to manually retrieve it and sail off, but the whole thing would have been much easier and far less nerve-wracking had we had the ability to just sail out of the situation.

In yet another, we wrapped a trap line on the prop in a wide channel with no traffic. Didn't have a sudden, emergency need for a sail that time, but what if it had been a little earlier, in the narrow and crowded part? Could have been quite the circus, with a conventional cover on the main and halyard down on a stanchion.

You see, you're kind of making my point for me. If you're sailing a boat that sails well, you're more likely to be ready to sail it anywhere, anytime just because it's a hell of a lot more fun that motorsailing some pig upwind in the Sir Francis Drake Channel. Seriously, if you own a sailboat that sails well, why in the hell would you be leaving port with your mainsail cover on and your halyard stowed away?

U'm the fancy boom bag systems you can leave them unzipped all day and all night if you choose the main sits nice all nestled down inside the proper sized bag. Only time we unhooked the halyard was at night. In fact I only zipped the bag twice in two weeks of cruising given we had some thunderstorms and I wanted to avoid any potential issues. funny thing is the charter capts parked on both sides of us never bothered I asked later and they said not once have they had to zip the bag to keep the sail put.

As for engine issues I've had those to - you lower the main and sail in to tight spots or the slip with the roller furler jib which by the way gives you way more control than any type of main when doing that sort of sailing given you can furl the jib in nearly any wind angle even from aft which you can't really do very well with RF mains.

My view on this is if you see attaching a halyard to a sail too much work then you might want to take up golf and get an electric kart.

And yes till you actually use a proper boom bag set up you have no idea what your missing. After our trip on the boat with the boom bag set up we decided right then our next boat would have one. Yes I've sailed roller Furler mains - I wasn't impressed the least bit everything from the shape of the terrible main to the owner freaking out about how you need to be really careful when you roll it up given he had it jam a few times and it took hours to get the damn thing sorted out.

 

[jjgeleceng]

<snip>...

I know I don't mean to argue here on CA I just try to pass along the few nuggets of sailing wisdom that have come down to me over the years so that people still, on the steep side of the learning curve can benefit from my efforts and learn a bit quicker.

And those of us that are aware of our ignorance thank you.

 

[MoeAlfa]

<snip>...

I know I don't mean to argue here on CA I just try to pass along the few nuggets of sailing wisdom that have come down to me over the years so that people still, on the steep side of the learning curve can benefit from my efforts and learn a bit quicker.

And those of us that are aware of our ignorance thank you.

Yes, indeed! This place is an ongoing lesson in how much I don't know. Almost as bad as racing.

 

[Bob Perry]

More2:

A day does not go by when I am not reminded of my own ignorance.

Today for example:

I used the boat very little for the last two years as we had moved to the new house and my 2 minute commute to the boat was now an hour and besides I had the new house to enjoy and my speedy Whaler.

So the boat sat at the dock idle.

My son went down to take it out.

Called me and said the sail drive transmission needs rebuilding as the boat would not go into gear.

"Don't wory Dad I'll order the parts to do it."

He's very good at things like that.

As wifey left for the haul out this morning I said, "Check the prop. It could be frozen folded and that's why the boat won't move."

She just called. Boat hauled and looking very good but just enoug barnacles on the folding Gori prop to prevent it from opening.

Son with a box full of sail drive parts and good intentions.

Ok, so I learned something.

Use the boat more!

Not a day goes by......

 

[Pertinacious Tom]

The flattening is outweighed by hooking the leech, but somebody earlier on made the point that tightening the leech line flattens the sail. I'd never thought about it, and probably never will aging but I think it's true, and nobody's refuted the rationale posted above.

Your rationale makes sense, but Bob is a really old sailing geezer. I don't know which is right, but if I had to bet money I'd go with old geezer over rational.

 

[Keith]

You see, you're kind of making my point for me. If you're sailing a boat that sails well, you're more likely to be ready to sail it anywhere, anytime just because it's a hell of a lot more fun that motorsailing some pig upwind in the Sir Francis Drake Channel. Seriously, if you own a sailboat that sails well, why in the hell would you be leaving port with your mainsail cover on and your halyard stowed away?

We needed to run the engine-driven refrigeration for an hour, so figured we would use that hour to get under way toward the Berry Islands. Why prep the sail sitting still at anchor and running the engine, when we could use the engine to get going? With the anchor up and stowed, the crew was about to get the cover off the sail and put it up when the engine quit.

Sailing usually requires you being a boy scout, "be prepared", and have all the gear ready to go, before you pull the anchor or leave the dock.... always thinking 2-3 steps ahead... with multiple options, if you need them... that gives you more control of the situation, and minimizes the Chinese fire drills in the crowded areas...

If its a charter boat, its tough to know how reliable the systems are... if its your boat, you usually know exactly what works reliably on board and what kinda works...

 

[Pertinacious Tom]

if its your boat, you usually know exactly what works reliably on board and what kinda works...

My boat, Perkins diesel only slightly less reliable than gravity, but a helpful friend did the fuel filters for me that morning and guess what he forgot to do last? You should have seen the look on his face as the engine choked and died. For that matter, you probably should have seen the look on mine too, but for a different reason!

 

[NoStrings]

It finally dawned on me why Lamps and his buddy "think" the leech line "flattens" the mainsail: assuming that the cleat is located on the leech above the clew (instead of coming over the top to a cleat at the tack), he had to sheet the main in fairly hard to even reach the damn thing. Presto, yanking on the leech line "must have" flattened the sail out. h34r:

Mystery solved.

 

[MoeAlfa]

If you don't play the leech line upwind, you're just giving away boats, is what you're doing! :lol:

 

[NoStrings]

I'm damn tempted to list that as a crew position on our Pac Cup entry...

 

[SpongeDeckSquareFoil]

If I replace my current leech cord with amsteel will I take a PHRF hit?

 

[Ishmael]

Non:

I have sailed on enough boats with in mast furling to be quite confident that adding tension to the leach line will just add curl to the leach. Been there and done that several times. Just look at all my Passport designs that were built with in mast furling.

It's just geometry. The sail draft has to go somewhere as the line is tensioned. Show me one pic of a boat,. hard on the wind in any breeze at all with an in mast furling main where the leach is not curled.

I absolutely agree that the leech will hook, but I still think that the sail will to some degree flatten, not maybe a lot, and probably won't de-power because you hooked the leech. The key is the degree of hollowness in the leech. Bob, in your genoa analogy the leech of the genny still has a little roach, whereas on a lot of roller mains the roach is negative. Imagine that put the boom vang on, and have a spare main halyard shackled to the end of the boom, and further imagine that you put hanks on a hollow leeched main and hank them onto the spare main halyard. Make the cutout really drastic (it is on my boat). Now tighten that spare main halyard and you will pull draft out of the sail, kind of like having a bunch of outhaul points higher up on the sail, or loosening the tension on full battens. Note that the key point here is the hollow leech on the sail; as you straighten that line you will stretch the sail out horizontally (and pull draft aft, ugh).

cheers,

Lamps

The flattening is outweighed by hooking the leech, but somebody earlier on made the point that tightening the leech line flattens the sail. I'd never thought about it, and probably never will aging but I think it's true, and nobody's refuted the rationale posted above.

Your rationale makes sense, but Bob is a really old sailing geezer. I don't know which is right, but if I had to bet money I'd go with old geezer over rational.

The way Lamps described how he thought his leech line worked is wrong because the leech line is pulling inside the tabling on the sail from the top down, effectively making the leech shorter. The extra sail fabric relaxes along the line, cupping the leech and making the sail slightly fuller right ahead of the leech. It's not like tensioning a stay which is putting equal strain up a row of hanks up the leech, which would flatten the back end of the sail.

 

[NoStrings]

Non:

I have sailed on enough boats with in mast furling to be quite confident that adding tension to the leach line will just add curl to the leach. Been there and done that several times. Just look at all my Passport designs that were built with in mast furling.

It's just geometry. The sail draft has to go somewhere as the line is tensioned. Show me one pic of a boat,. hard on the wind in any breeze at all with an in mast furling main where the leach is not curled.

I absolutely agree that the leech will hook, but I still think that the sail will to some degree flatten, not maybe a lot, and probably won't de-power because you hooked the leech. The key is the degree of hollowness in the leech. Bob, in your genoa analogy the leech of the genny still has a little roach, whereas on a lot of roller mains the roach is negative. Imagine that put the boom vang on, and have a spare main halyard shackled to the end of the boom, and further imagine that you put hanks on a hollow leeched main and hank them onto the spare main halyard. Make the cutout really drastic (it is on my boat). Now tighten that spare main halyard and you will pull draft out of the sail, kind of like having a bunch of outhaul points higher up on the sail, or loosening the tension on full battens. Note that the key point here is the hollow leech on the sail; as you straighten that line you will stretch the sail out horizontally (and pull draft aft, ugh).

cheers,

Lamps

The flattening is outweighed by hooking the leech, but somebody earlier on made the point that tightening the leech line flattens the sail. I'd never thought about it, and probably never will aging but I think it's true, and nobody's refuted the rationale posted above.

Your rationale makes sense, but Bob is a really old sailing geezer. I don't know which is right, but if I had to bet money I'd go with old geezer over rational.

The way Lamps described how he thought his leech line worked is wrong because the leech line is pulling inside the tabling on the sail from the top down, effectively making the leech shorter. The extra sail fabric relaxes along the line, cupping the leech and making the sail slightly fuller right ahead of the leech. It's not like tensioning a stay which is putting equal strain up a row of hanks up the leech, which would flatten the back end of the sail.

No...really? <_<

 

[MoeAlfa]

I'm damn tempted to list that as a crew position on our Pac Cup entry...

Dude, I'm your man! I'll only weigh 156 after I donate that second kidney.

 

[sailorbob]

The ONLY reason for a leech line is to git the leech some stability. It should only be tensioned lightly to remove the flutttering or "motorboating" of the aft edge of the sail. Motorboating results in rapid oscillations of the trailing sail edge meaning the pressue is also oscillating (not a good thing) which means the pressure is rapidly changing on both sides of the sails training edge. If you need to crank on the leech line so much that it cups the sail, it would be like trying to fly a plane with the flaps deployed..... not good for efficient flight or boat speed. If you have a sail like this get it back into the loft and have them recut the aft edges of the pannel to flatten it out!

 

[Pertinacious Tom]

The way Lamps described how he thought his leech line worked is wrong because the leech line is pulling inside the tabling on the sail from the top down, effectively making the leech shorter. The extra sail fabric relaxes along the line, cupping the leech and making the sail slightly fuller right ahead of the leech. It's not like tensioning a stay which is putting equal strain up a row of hanks up the leech, which would flatten the back end of the sail.

Ish are you even older than Bob?

 

[us7070]

The ONLY reason for a leech line is to git the leech some stability. It should only be tensioned lightly to remove the flutttering or "motorboating" of the aft edge of the sail. Motorboating results in rapid oscillations of the trailing sail edge meaning the pressue is also oscillating (not a good thing) which means the pressure is rapidly changing on both sides of the sails training edge. If you need to crank on the leech line so much that it cups the sail, it would be like trying to fly a plane with the flaps deployed..... not good for efficient flight or boat speed. If you have a sail like this get it back into the loft and have them recut the aft edges of the pannel to flatten it out!

it's a good thing leech lines usually slip, because it's easy to do more harm than good with them.

 

[Lamps]

It finally dawned on me why Lamps and his buddy "think" the leech line "flattens" the mainsail: assuming that the cleat is located on the leech above the clew (instead of coming over the top to a cleat at the tack), he had to sheet the main in fairly hard to even reach the damn thing. Presto, yanking on the leech line "must have" flattened the sail out. h34r:

Mystery solved.

No, my leech line trimmer sits on the end of the boom, we don`t have to sheet in to adjust, just pass beers to him when he calls for them.

Lamps