Reefing Mainsail Downwind

[waterman46]

I have been reading several posts on another thread, where reefing downwind in a blow is claimed to be possible. The discussion there was in-mast vs in-boom vs standard mainsail rigging. I am not familiar with any other than standard main with and without full battens.

I have always found it necessary to come up to a beam reach or higher, to free the main from the spreader and stays so it can be lowered and the clew tightened with the reefing line

What is the reefing procedure for in-mast or in-boom, that allows some to claim they can reef downwind? Is it done with the mainsail lying against the spreaders or is the mainsheet brought in?

Must the boom must be centered enough to free the sail from the standing rigging? I am only concerned with reefing in rough conditions, where it is not possible to maintain directional control of the boat for more than a few seconds under autopilot if the boom is brought in near centerline and risking accidental jibe or broach.

[Banderson]

When I have another set of hands, I have found it very easy to reef running downwind. Even on a broad reach it works nicely. Gybe the boat, and as the main goes slack through the wind, yank it down quickly. On my boat, if I want to put in a double reef, I get the first on the gybe over and the second on the gybe back to my course.

[LoudMusic]

I'm looking forward to responses on this as well. We are considering a boom furling main on our catamaran.

It's my understanding that the manufacturers want the boom within a couple degrees of centerline. But really the big issue is having the pitch of the boom as near to 90 degrees of the mast so that it rolls smoothly. Boom swing angle mostly creates friction drag as the sail rolls into the mast or into the boom.

Or I'm misunderstanding it altogether

[LoudMusic]

Originally Posted by Banderson

When I have another set of hands, I have found it very easy to reef running downwind. Even on a broad reach it works nicely. Gybe the boat, and as the main goes slack through the wind, yank it down quickly. On my boat, if I want to put in a double reef, I get the first on the gybe over and the second on the gybe back to my course.

Sounds like you have a boom furler then? What brand/size?

[tomfl]

It is quite possible to reef going DW. But it can also be impossible to do it. The key is how fast your boat is going in relation to the wind. There are some very fast monohulls, and even more fast multihulls, that are going so fast DW compared to the TWS that reefing is not an issue. For some monohulls and condomarans their DW speed is so slow compared to the TWS reefing can be an issue. Another advantage the faster boats have is often their traveler is so big it allows adjustments that reduce forces helping to reef. Basically the answer to your question is very boat specific and to some extent conditions specific as well.

[Pete7]

To reef or furl away our in-mast main when sailing down wind I bring the main nearly all the way in to the centre then slowly release the outhaul which is attached to the clew whilst either pulling in the continuous furling line or winch it in, to furl the sail in the mast.

The sail furls slightly easier when on a port tack as the sail is wound anti clockwise when viewed from above and doesn't run on the curved edge of the mast slot. Also I do try to avoid furling with the sail against the stays. There are no patches or batten pockets to worry about, but I think its worth taking a moment to look after sails so they last.

Pete

[waterman46]

OP here, and thanks for the suggestions. Yes I have no doubt that on a very fast boat downeind sail work is easier due to much reduced relative windspeed. Used to watch the easy spinnaker gibes on MacGregor 65's as they shot by my Cal29 while we struggled a bit,. Now I have bigger boat but it is no faster. So in 25 knots I still have 17 knots relative.

Yes if ever I have experienced helmsman to help, I can center the boom long enough to move forward to the mast and yank down the sail to the reef point. Maybe. Once the sail is lowered a couple feet, the resulting slack in the leech allows the sail to snuggle up hard against the standing rigging again so the clew reefing line may need to be tightened in stages to get down to the actual reef point. But my question was about singlehanding and first I will see if the pilot can hold course reliably DDW in 25 knots and accompanying seas for 5 minutes with boom centered. I am doubtful.

[ausnp84]

Interested in this as I have Pro Furl in-boom furling on a cruising cat. In theory, it should just be a case of centering the traveller then furling the main as halyard tension is loosened.... theory and practice are of course rather different!!

N

[a64pilot]

I can reef downwind, but the force required to do so is so much less when the sail is into the wind and luffing, that I don’t reef downwind. My reasoning may not be sound but when you have to pull so hard on a line to do something, but if you change something it’s so much easier, logic would seem to dictate to do it when the forces are lessened, surely it has to be easier on the equipment then.
What makes it harder to reef when going downwind is the line (bolt rope?) in the sail that goes into the track is being pulled on, and this is a whole lot of friction. If your into the wind, the line is not being pulled into the track, much, much less friction.
But if caught out with full sail and running hard downwind, I’d reef. We actually were in that situation or at least I should have reefed, the boat was handling it fine though, we were running downwind and surfing at 10+ kts, when surfing, it was kind of fun, although the Wife didn’t like the size of the waves.
I was sort of enjoying it. The Autopilot was handling it fine, then suddenly it wasn’t, we had an accidental jibe that tore the end cap and the car off of the traveller and the boom was completely free.
Winds over 25 kts. Not a whole lot over but it takes that get get my boat to surf, she is no performance boat. It’s the only time we have ever surfed too.

Thankfully no permanent harm, the boom did slam very hard into both stays, but I was able to get it under control and the sail down without hurting myself or the boat.
I have now finished the installation of the boom brake that I was going to get around to one day. Suddenly I found the motivation

Boom angle is not 90 degrees, you would think it should be logically. But for some reason it’s not, it’s I believe on mine 96 degrees? Tail end of the boom, up.
It real easy to find though if sail is being jammed forward, boom angle is too low, if it walks to the rear, the tail end is too high. Nothing bad happens if it walks forward or rearward, it just jams agains the end of the boom which makes it harder to overcome the friction, but it will still furl, just way harder to do so, when the angle is correct and the sail isn’t being jammed forward, it furls a whole lot easier.

It’s like anything else, if you get a sudden increase in resistance, stop and investigate, don’t just power thru with the electric winch

[a64pilot]

You don’t need the boom centered to reef, the pivot point of the boom and the sail track and therefore the sail line up, so as the boom moves, its relationship to the sail track and sail don’t change.
What makes it hard is of course wind causes the sail to pull on the rope that is in the track, increasing friction, I’d assume a regular sail is the same?

Mine is a Pro Furl

[daletournier]

I used to furl (reef) my sparcraft inmast downwind,I'd do it little by little and use the roll of the boat to assist.

I know longer do this,the load is to great for my comfort. I now furl the head sail then turn beam on. It's very fast with the electric winch , probably about 15 -20 secs once in position.

I also have a dutchman boom brake, has saved my butt a couple of times.

[44'cruisingcat]

Originally Posted by tomfl

It is quite possible to reef going DW. But it can also be impossible to do it. The key is how fast your boat is going in relation to the wind. There are some very fast monohulls, and even more fast multihulls, that are going so fast DW compared to the TWS that reefing is not an issue. For some monohulls and condomarans their DW speed is so slow compared to the TWS reefing can be an issue. Another advantage the faster boats have is often their traveler is so big it allows adjustments that reduce forces helping to reef. Basically the answer to your question is very boat specific and to some extent conditions specific as well.

This.

It's also a point of sail where there is a major difference between cat's and mono's.

It's easy for an autopilot to hold a DDW or near DDW course on a cat. There's no deep rolling, no tendency to broach.

The method I use reefing downwind takes a couple of minutes. But the autopilot has no problems holding course, so the time it takes really doesn't matter.

Edit: Having a fully battened main with batten cars doesn't hurt either. The battens help keep the sail from getting too wrapped up in the standing rigging.

[Breaking Waves]

Originally Posted by waterman46

where reefing downwind in a blow is claimed to be possible.

ummm.....I have not seen the other thread you reference, but reefing downwind (with a conventional main/boom) is very certainly possible. I did it frequently on a large-ish mainsail (71m^2/765 sq ft) fractional sloop.

It definitely helps to have excellent (ball bearing) sail slides - like harken batt cars. But the only real process 'trick' is you tension the reefing leach line continuously thru the process. That keeps the sail flat above the reef point and prevents it from bagging out around the stays and spreaders.

It is definitely not as fast as some other procedures. But sometimes you do not want to turn up (nor jybe).

[JPA Cate]

Waterman 46,

We have a fairly large main on this boat, ~65 sq. m., no fancy cars, just slugs. It is a bear to reef going downwind. We often come up to reef, which is easier on both of us.
Jim and I work together to do it. We bring the mainsail in towards amidships, but only about as far as one would use sailing 50-60 d. apparent wind. Then, as he eases the halyard, I bring in the reefing line, keeping an eye also on how much slack is in the main sheet, so I have two things to watch. The trick is to leave a little slack in the reefing line, and enough in the main so that when he has tensioned the halyard, there's enough ease to snug down the reef line. From there it's just tidy up the lines, and ease out the main to its proper trim for the course. Please feel free to question me about this, it is a process I find difficult to execute well, and I may have left something critical out of my description.

Fwiw, I use the Milwaukee rt. angle drill motor, with the winch bit, to bring in the reefing line, it is much faster than I am at cranking, and I wedge myself in the companionway because when we're rolling around, I need the stability. "Milly" is heavy and bulky, quite a handful, actually, but very helpful for me.

Ann

[Cpt Pat]

Heave to. Let the main out till it's nearly against the shrouds. Haul your jibsheet so the jib is taken aback, if necessary. Tie off the tiller/wheel if single-handing (steer hard to windward). Reef the main. Resume downwind course if desired.

Caveat: Boats with fin keels my be squirrelly and do "S" turns during the operation.