Latest News: Forums Cruising How big is your reef?

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  • #3689
    John1162
    Member

    Matt’s previous post on waves prompted me to look at the youtube link from matoi. I can recall sailing through waves as big as those shown on the video and I remember seeing Matt going through them before me. What came to mind was how much sail would I have had up in the same situation. I note that the waves were rapidly catching the boat up and so I would have had more sail up to increase my forward speed.

    When’s he going to get to the bit about reefing I hear you say. Well after looking at the video I had a look at my notes on my reefs and thought I would share some thoughts with you.

    My first reef is 1.3m up from the boom and my second one is a further 1.1m. My foresail is on a roller reefing spar and so I can set any area I want. Just so you don’t have to work it out, my mainsail areas are: Full main then the first reef leaves me with 6.4sq m the second reef leaves me with 4.2sq m. For comparison a genoa set as a trysail would give 4.23sq m but with a higher centre of effort.

    How well does it work?
    In a force 6 with two reefs and two people on board the crew doesn’t need to sit on the side deck apart from when a gust hits. In sheltered waters it really is quite comfortable. When the wind picks up a bit more to a 7 with gusts on top then it is quite exhilarating.
    I tend to reef early and with one reef in say the top end of a 3 to a 4 again it is still comfortable. When I am cruising, my wife prefers to sit in the boat rather than on it.

    To thoes of you reading this who are new to sailing remember that all this talk of sailing in strong winds comes on the back of over 30years sailing and not just anyone can do it. I might add that I am used to capsizing a racing dinghy. Remember the RS500 Matt?

    I have had sails where the first reef was below the first batten and I always thought it just wasn’t big enough. When I sail with my first, huge, reef and other boats have a smaller reef I haven’t noticed any difference in speed between boats but I have noticed that my crew doesn’t sit out as much.

    So there we have it. How big is your reef?

    #6752
    matoi
    Member

    Hi John!

    Thank you for the post and for sharing your experience. Just a month ago I was thinking about sending you, Matt and Ralph a private message asking about these measures. It seems that many experienced W cruisers use this ‘deep reefing line’. When the boats were lined up for the reefing contest at the Tidal Training in November, it was easily noticed – the first two boats in the foreground are Matt’s and Ralph’s and they both have it that way.

    Also, before some time, there was a post on the forum XXXXXX, which seemed very similar to your experience. All this made me take my mainsail to the sailmakers’ just a few weeks ago in order to have them install a deep reefing line (between the standard #1 and #2 line) which should be just like yours. My plan is to forget the standard #1 and #2 line and use just this middle deep reef. Prior to making a definitive decision, I also made a little graphical analysis of the sail plan.

    There is a bigger picture at:

    http://sail.zpf.fer.hr/mato/razno/sailPlanBig.jpg

    I did this in a very primitive way, so it might be off somewhat. Anyone’s comments are more than welcome. When I talked to my sailmaker-friend he told me that these geometrical/theoretical analysis are not to be blindly relied upon. But I feel that generally it is ok as it shows the CE of full main + genoa in line whit the centreboard. What is interesting is that CE of full main + jib is more or less in the same place, the smaller area of jib is compensated by the jib’s CE being in front of genoa’s CE. Another thing that can be seen is that CE of #2 main reef + genoa is well in front of centreboard which is confirmed in reality by strong lee helm and advice by experienced sailors not to ever sail under #2 reef and genoa at the same time. What surprised me a bit is that CE of #2 main reef + jib is also well forward, close to the dreaded CE of #2 main reef + genoa. A disgusting discovery that made me finally confident about abandoning this reef and installing the middle ‘deep reef’. Of course, the standard #2 reef would probably be perfectly ok if I had that reefing foresail system – but I don’t.

    What I also thought about is that genoa/trysail idea. What made me actually interested in the concept is the book “The Open Boat” by Webb Chiles about his circumnavigation attempt in Drascombe Lugger (free to download from: http://inthepresentsea.com/books.html). It seems that the boomless aspect of his rig provided a lot of comfort in certain situations. That is why I also asked my friends to make a 5 m2 mainsail / trysail for the Wayfarer which would be used without the boom, using spinnaker sheet blocks on sidedecks. They are not charging me much for this so it is primarily something to play with when an occasion turns up. I hope that until autumn I will have some experience to share.

    Your comment about the ‘Anita im orkan’ video, and having more sail area is also something that I find interesting. At sailing courses and in textbooks, beginners are allways advised to reef early, and to control/reduce the speed when sailing downwind in order to minimize the chances of broaching. But this video, and your comment, warn that speed is important for maintaining control and that there is a speed limit below which the rudder won’t have proper effect when sailing downwind. If I understand correctly – on the upper half of the wave, the water particles flow in the direction of the waves, while in the lower half water flows in the opposite direction. So when sailing downwind, while the boat is in the trough, the flow of the water goes against the boat – adding itself to the speed of the boat, and so helping the rudder to work nicely. But on the upper half of the wave, the waterflow goes together with the boat and if the boat speed is equal or less than the flow of the water – moving the rudder will be equally ineffective as moving it in a boat that has speed 0 in a calm sea. Is this in accordance with your experience ? I have made a little animation for an imaginary situation (an 8MB animated gif):

    http://sail.zpf.fer.hr/mato/razno/downwind.gif

    If this theory isn’t wrong, it shows that the boat speed in such sitation actually needs to be considerable – in order to keep the rudder effective and everything safe.

    Comments welcome!

    Best regards,

    Mato

    #6753
    Bob Harland
    Participant

    We have always gone for a reef position that gives you a balanced sail plan with whatever foresail you have. As Matoi says it’s the balance fore and aft that is important; with lee helm tacking is difficult, whereas weather helm is very tiring on the tiller.

    In addition to the genoa we carry a standard jib and a (less common) storm jib. With 2 reef points 1 metre and 2 metres above the boom this gives a good compromise.
    Experience shows that the boat is fairly well balanced with the jib plus 1 reef.
    You can manage quite well with jib plus 2 reefs, but the boat clearly carries lee helm and makes a heavy job of tacking. So it’s not an ideal combination if you are hard on the wind.

      1st reef If the wind is pushing the top end of F4 and we are going to windward for any distance then that’s the time to take in the first reef and change down to the jib.
      2nd reef At sea, once the wind is at the top end of F5 we would pull in the second reef. As long as we are not hard on the wind this is fine.
      Storm jib If the wind is F6 or more then 2 reefs and storm jib are very nicely balanced. You can easily short tack in confined waters. Whereas the working jib is more likely to miss stays.

    Although the centre of effort (CE) shown in Matoi’s excellent diagram is important it is also about the amount of flogging sail cloth as the boat tacks through the wind. In this respect the genoa is truly awful and the storm jib presents little resistance.

    I think if you take off much more mainsail than 2 metres then the efficiency drops and your ability to make to windward is pretty poor. So you might as well run downwind under a jib. And when you are telling your sailmaker where to put the reef points 1m & 2m is an easy number to remember.

    bob
    W7658

    #6754
    Dave Barker
    Keymaster

    All interesting stuff and food for thought.

    To answer your question directly, John, first reef 900mm, second a further 900mm. These are deeper than on the sail I inherited with the boat, but perhaps I would go to 1m spacings another time…

    I look forward to more quality discussion of reefing (and much else) at the Cruising Conference.

    #6755
    matoi
    Member

    Hi Bob!

    Could you please post the dimensions of your storm jib?

    Thank you + best regards,

    Mato

    #6756
    Anonymous
    Inactive

    Thanks for the post John. Good info, glad Matt’s post has developed .
    As I am unlikely to get to the cruising conference for a few years yet and am not in a club this is “the source”. So the related question I have sat on for a good while is this. Who goes faster………the boat sailed flat and reefed (with balanced sails) or the more overpowered boat with full sail heeling over? Obviously this might be a naieve over-simplified question but this is the place to ask 😀

    #6757
    Dave8181
    Member

    @Dave Mac wrote:

    Who goes faster………the boat sailed flat and reefed (with balanced sails) or the more overpowered boat with full sail heeling over? Obviously this might be a naive over-simplified question but this is the place to ask.

    In heavily overpowered conditions, I have used a reefed (1m) main and short foot genoa (half way between genoa and jib) to race against Wayfarers with full sail. The full size sailed boats flattened their sails and spilled wind from the sails to stay flat. Upwind my boat had equal speed and pointing, but with much less effort from the crew. From this I would suspect that a reefed boat would do better than a boat beating under “full sail heeling over”, which would have worse pointing and leeway. Once we reached the windward mark and turned offwind however, we were slower.

    @matoi wrote:

    But on the upper half of the wave, the waterflow goes together with the boat and if the boat speed is equal or less than the flow of the water – moving the rudder will be equally ineffective as moving it in a boat that has speed 0 in a calm sea. Is this in accordance with your experience ? I have made a little animation for an imaginary situation

    Like the animation! The rudder requires flow to be effective, however unlike the yacht in the video, a dinghy can, to some extent, also be controlled by the crew moving to adjust the angle of heel. This can help steer and balance the turning forces on the boat, by moving the mast and C of E of the sail out to the side. E.g. heel the boat to windward and it will tend to bear away. So by this means the boat can be partly held on course, with less rudder movement, or if the rudder is momentarily ineffective.

    Dave8181

    #6768
    Bob Harland
    Participant

    @matoi wrote:

    Hi Bob!

    Could you please post the dimensions of your storm jib?

    Thank you + best regards,

    Mato

    2950mm
    2170mm
    1490mm
    and we have a short wire strop at the tack and a longer one for the head so that the overall length is the same as genoa.

    #6772
    matoi
    Member

    Thank you Bob!

    I’ll update the picture to include your storm jib when I catch some time.

    Best wishes!

    Mato

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