Position of reefing points on new mainsail

srah1953

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Hello all
I'm looking for thoughts please on a reefing set-up for a a new mainsail I'm getting made in a cruising laminate.
My boom is set up for 2 single line reefs. Three reefs would require extra turning blocks and clutches but is feasible.
I'm never going to cross oceans and try to only go out in reasonable winds but, obviously, there is no guarantee of not getting caught out.
For a three reef set-up, the sailmaker has said that they would tend to set up at around 15, 30 and 45% of luff length and, for 2 reefs, he has suggested reefs at 15% and 40% of luff length. I was thinking more of 20% and 45% of luff length? Obviously, the sail area reduction would be significantly more than the % of luff length.
I would welcome thoughts.
Thanks
 
When i bought my new Hyde main sail they said it could only have 2 reefs with laminate as the balance of cloth would be spoiled by putting strangthening patches & bias in the top of the sail which would not balance the lower part of the sail
I, therefore, went for marblehead racing & they had no problem with 3 reefs
I made sure they had the dims from my old sail so that the lines coincided with the slots in my sail cover ( lazyjack system)

My current system is single line reefing from the cockpit on the first 2 reefs ( never failed me & fast & reliable)
The third reef hardle ever gets used & I have a system whereby the luff fixes to the mast with a strop ( done at the mast) & the clew is held down by attaching the first outhaul to a strop which lays in the sailbag ready to use. This gives a bullet proof system for serious weather
Of course if I thought it was going to be rough I can set off with 2nd reef & transfer the first reef to the third reef as it would not have to go far up the mast but that would be hassle

Leaving a 3rd reef permanently set on a single line system would be total agro with too much line to stow or get tangled
 
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3 reefs with a 2-reef system is perfectly feasible without extra lines and gear. Reeve a continuous length of light line through the leech cringles of reefs 2 and 3. It is then easy to swap the No1 pennant to the No3 reef when you already have the 2nd reef in. You won't do it very often but it can be a godsend if you feel the need.
 
Depends on the boat and how it is used.
We cruise West Scotland and Ireland but not in mid winter. I have three reefs on the main on our Finngulf 33 but have not yet (in 6 seasons) experienced the conditions that would demand the third one. I no longer reeve the reefing line for it, though the boom carries three reefing lines. This is our fifth cruising yacht in a period of 40 odd years, I have done a bit of 'offshore' racing in the past (in Sigmas) but that was not real offshore but just in the Irish Sea between N. Ireland, Isle of Man and Scotland and we were never forced to use a trysail or third reef, or even the storm jib, though sometimes the wind speed was a bit over 40 kts.
We no longer go to sea if conditions over force 7-8 are forecast and the forecasts are pretty reliable these days but it would be different if we were sailing all year round or making three day or longer passages to Norway or Spain.
It would be a very tender boat or ambitious owner that would need a 45% reef. A small reduction 15% for use when the wind gets above force 5 would be a lot more useful with a 30% reduction available for winds up to 7 or 8. If your genoa is more than 140% you will need to reduce it anyway to get balance but with a 105% blade you will be able to reef much later, we carry both.
 
Much depends on how big a rig your boat has. A solid cruising yacht with a deep and heavy keel and a relatively small sail area to displacement ratio will need less reefing than a racier boat with a big rig and a high sail area to displacement ratio. The starting point is to consider the wind speed that causes you to want to start reefing with the wind on the beam. With the deep reef at 40% of the luff you only have about 36% of the sail area when reefed, and the centre of effort has been considerably lowered, such that the force trying to put the boat onto its side is probably only a quarter of what you would have had with full sail up. The type of boat and its sail plan determines how deep the reefs need to be, so there can be no universal solution.

I don't have to reef on a beam reach until the wind is over 20 knots, and the first reef is all I usually need. For what its worth my own boat has two reefs, and the first reef is not as much as 15%. I have single line reefing for the first reef, and twin line for the second. Given the amount of line that has to pulled in for a deep reef, and the amount of friction in most single line systems I suggest that if you go for three reefs get extra turning blocks and clutches and go for a twin line setup, or simply go for slab reefing, hooking the cringle onto the rams horn at the mast.
 
3 reefs with a 2-reef system is perfectly feasible without extra lines and gear. Reeve a continuous length of light line through the leech cringles of reefs 2 and 3. It is then easy to swap the No1 pennant to the No3 reef when you already have the 2nd reef in. You won't do it very often but it can be a godsend if you feel the need.

Thanks for the comments. The boat is a 39 ft Sun Odyssey with a shallow keel and a 30% ballast ratio.
In relation to the above comment, I don't really follow how this would work. The end of the 1st reef line when taking place of 3rd reef will have to be re-tied around the boom at a different position, not something I'd want to tackling in such conditions. Or am I missing something?
 
The end of the 1st reef line when taking place of 3rd reef will have to be re-tied around the boom at a different position, not something I'd want to tackling in such conditions. Or am I missing something?

My understanding is the same as yours, and I'm inclined to agree with your conclusion too :)

I currently leave my third reef lines (separate tack and clew pendants) rove through as far as the boom and then a stopper tied in the end. So the clew pendant ends at the end of the boom, and most of its length is in a coil in the cockpit. Before setting out on a trip that looks like being rough, I pull it through and rig it while still moored up.

Over this winter I'm planning to replace all the reef pendants with thinner dyneema, and I hope that the reduced bulk and friction will make it feasible to leave all three reefs rigged all the time.

Pete
 
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Thanks for the comments. The boat is a 39 ft Sun Odyssey with a shallow keel and a 30% ballast ratio.
In relation to the above comment, I don't really follow how this would work. The end of the 1st reef line when taking place of 3rd reef will have to be re-tied around the boom at a different position, not something I'd want to tackling in such conditions. Or am I missing something?

No, you are not missing something. If you can't tie a bowline 'cos it's too high up then it is obviously not for you. On my boat and with my gorilla-like arms it is relatively easy.
 
No, you are not missing something. If you can't tie a bowline 'cos it's too high up then it is obviously not for you.

I have to stand with one foot on the cockpit coaming and one on the top of the binnacle, to reach that area on my boom. Not somewhere I want to be in three-reef weather :)

Pete
 
If you have a Selden boom with single reefing line, the height of the reef depends of the length of the boom and is specified by Selden
 
3 reefs with a 2-reef system is perfectly feasible without extra lines and gear. Reeve a continuous length of light line through the leech cringles of reefs 2 and 3. It is then easy to swap the No1 pennant to the No3 reef when you already have the 2nd reef in. You won't do it very often but it can be a godsend if you feel the need.

This is the method we use on our boat. (44 foot sloop, masthead rig). Works a treat. Admittedly the boom is easily accessible. Just one proviso. Ensure the knot holding No. 1 reef in is easily untied ! (Ask me how I know this is important !).
Chris
 
I have been thinking along rather similar lines. Originally my boat (just a 25-foot sloop with a self tacking jib) had two (usable) reef points. It used an utterly hopeless single-line system for both reefs. After much attention to reduce friction as far as possible (small ball-bearing blocks everywhere, and thin low-stretch lines, no problem with chafe after several seasons) the system became usable and worked quite well, it was now easy to reef and shake out a reef without leaving the cockpit. Anyway. The second reef was fine for any weather I would choose to be out in, but obviously one can get caught out, so after much thought I had a third set of reef points (just in luff and leech, no intermediates which were not needed as I had lazyjacks at first and now a stack-pack) put in. The idea was that if the weather looked iffy I could swap the line for the first reef into the points for the third reef, before setting out. I have actually only done this once, for about a F7, it worked well.

I have now ordered a long-overdue new main and jib, and the main will have 3 reefs. I think I can rig 3 sets of reef lines, but if this doesn't work or is altogether too much string, I will go for having to take a trip to the mast for the third reef which shouldn't be a problem, but I will try to still have a line for the third reef point in the leech. If that doesn't work we are back to plan A as above, but would much prefer to avoid having to swap lines around.
 
No, you are not missing something. If you can't tie a bowline 'cos it's too high up then it is obviously not for you. On my boat and with my gorilla-like arms it is relatively easy.

As a point of pedancy, the bowline doesn't go round the boom, but more properly tied as a running bowline on the reefing pennant itself after the reefing line has passed under the boom. In theory and if you have enough slack, you could tie the bowline sitting down in the cockpit once you'd threaded the line through or under the boom and grabbed a bight of the pennant to tie the bowline round.

Release the topping lift & drop the boom end into the cockpit
When the mainsail is set with two reefs and you are thinking you might need a third one any minute? You'd have to lower the main halyard lots and there would be mainsail flogging all over the place for a while which wouldn't do you or the mainsail any good. In addition, the OP says he has a stack pack so the lazyjacks would prevent the boom from dropping too far.


After reading the discussion so far, I think some people are forgetting that the force of the wind goes up with the square of the windspeed. The difference between 10 & 20 knots is very different to the difference between 30 and 40 knots. Coded boats require a deep third reef OR a trysail. You could stick with two reefs, but get a track on the mast and a trysail for really heavy weather or survival conditions.

I'm delighted to hear that some people have sorted their single line reefing systems out as I have always found them a pain in the posterior.

A compromise to those who don't want to go forward at all would be a two line system for the third reef with a downhaul set up at the mast from the third reefing tack eye and lead back to the cockpit. In fact you could leave it stowed for much of the time, but if bad weather looked possible, you could rig the tack downhaul on the third reef 'in case'. The third reefing pennant could be rigged permanently but wouldn't produce lots of string in the cockpit when putting the first and second reefs in using the single line reefing systems already in place.

FWIW we have reefing lines ready set up for three reefs but go to the mast to hook on the tack in the old fashioned way. Halyards and reefing pennants are all controlled from the cockpit. Its simple and works well...
 
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Thanks for the comments. The boat is a 39 ft Sun Odyssey with a shallow keel and a 30% ballast ratio.
In relation to the above comment, I don't really follow how this would work. The end of the 1st reef line when taking place of 3rd reef will have to be re-tied around the boom at a different position, not something I'd want to tackling in such conditions. Or am I missing something?
I have a deep-keel Sun Odyssey 35, probably similar handling in a middling blow to your shallow keel 39, and the standard 2 reefs are not small enough for going to windward in 35 knots true in open water, as well as reefing main and genoa you have to feather the 2-reefed main off. I had a third set of non-reeved reef points put in after finding this. I did not find that this was enough wind to justify setting the storm jib though (I have a removable inner forestay and hank-on sail). I think you do want a really deep reef even though it need not be permanently rigged.

You find these things out when you set off on a passage with a timetable (flight to catch at other end) !
 
I have a deep-keel Sun Odyssey 35, probably similar handling in a middling blow to your shallow keel 39, and the standard 2 reefs are not small enough for going to windward in 35 knots true in open water, as well as reefing main and genoa you have to feather the 2-reefed main off. I had a third set of non-reeved reef points put in after finding this. I did not find that this was enough wind to justify setting the storm jib though (I have a removable inner forestay and hank-on sail). I think you do want a really deep reef even though it need not be permanently rigged.

You find these things out when you set off on a passage with a timetable (flight to catch at other end) !

Where roughly on the luff (up from the boom) would you view this 3rd reef being placed?
Thanks
 
I took a bit more off going up vertically than the distances between the first two reef points: laid the sail out on the sailmakers floor and guessed. Batten positions also affected the choice.
 
My first 2 reefs are single line. The third reef is 2 lines, the one at he luff doubles as my cunningham, I switch it to the third cringle if required. and I normally don't rig the one to the outhaul just leave it with a stopper knot ready to be rigged if required. (I've got the deep keel, fractional Moody S38)
 
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