Alberg 30 Conversion Viability

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  • 26 May 2020 15:44
    Reply # 8993171 on 8981050

    Graeme wrote:...the current debate should probably not be taking place on this thread

    Agree.  I've found the other thread ("ruffled feathers") and have provided my own recollections of the notorious River Rat Brixham incident for the record, however late in the day.

    Last modified: 26 May 2020 15:51 | Anonymous member
  • 23 May 2020 00:03
    Reply # 8987568 on 8975930
    Anonymous member (Administrator)

    I happen to strongly concur with Slieve in his latest post (making allowance for the understandably passionate nature of it), but this thread is about the conversion viability of Ryan's Alberg 30 and I think Ryan has already made a rational decision on mast placement which means he may now prefer to focus on the alternative rigs.

    This means that the current debate should probably not be taking place on this thread, and I am directing this remark to David who has in the past been, quite rightly, a stickler for topic relevance. 

    Last modified: 23 May 2020 07:12 | Anonymous member (Administrator)
  • 22 May 2020 22:37
    Reply # 8987445 on 8975930

    In Reply # 8984860 on 21/5 @ 20:09 I wrote, “Whenever someone writes something positive about the SJR on the website it is an odds on bet that within 24 hours you will respond with a two point post.”

    So Edward writes today at 10:43 answering some interesting points, and explaining exactly why the information is being misunderstood, based on his own practical experience, and he gets the headmaster's comments at 12:10. So the marking service now only takes one hour and twenty seven minutes.

    Yet again you post is negative and does nothing to advance the pool of knowledge. There is no point in going on about flapping, fluttering and flogging when those who actually use the rig do not have a problem with it. OK, if you go out of your way, as I have done, and abuse the rig it is possible to do these things and yes, I have done a destruction test to see how 'dangerous' as position you could end up in. I know of no other junk rig experimenter who has done a similar test, so perhaps other rigs should not be allowed to sail off shore. In fact if you are worried about such things then Bermudan sloops should not be allowed off shore at their jib can flog to death.

    Actually, the jibs on the SJR had relatively short chord and relative short leeches, from batten to batten, so if forced to flog the destructive forces are much lower than on even a small working jib with its wider chord and full length leech, AND a shredded Bermudan jib at the wrong time could drop a sailor into big trouble.

    Sorry David, yet again you are flogging a dead horse with you uninformed comments.

    Similarly with you comments that no one has taken a SJR across an ocean, which is obviously your yardstick, so it shouldn't be done. Thank goodness Wilbur didn't have such a closed mind or we would all be sitting on the beach looking at the seagulls. Apollo 11 would be still sitting on the launch ramp waiting for someone to light the blue touch paper. To my knowledge no one has got into serious trouble with the integrity of a properly set up SJR to date, and my only embarrassments have been due to its better than Bermudan performance which we all know about. The same can not be said about some other junk rigs which no doubt you would cross an ocean with.

    David, you write, “but until the pioneering has been done and there is some breadth and depth of experience, I for one cannot do other than advocate conservative design and robust construction”. I could draw up a conservative and robust design very easily. Based on you standards, we'll use 15% chord balance, which would require a steeper yard angle than optimum, and possibly less main camber that we are using. Now taking the slot out of the 15% jibs would leave a jib pretty well impossible to shape with sheeting angel and camber so it would be best to attach it to the luff of the main panels, and guess what, you end up with a flat HM rig. That would prove absolutely nothing. If anyone is going to build a SJR then it would seem reasonable to use the latest tested results and build a SJR. A couple of people have tried to remove some features and have not received the full advantages of the rig.

    David, your repetitive unproven doubts are doing nothing to expand the pool of knowledge. A number of very sensible questions have been asked in this thread which I could answer from tested results, but frankly I see no point if you are going to follow up with negative uninformed and pointless guesses. I have much more to do with my time.

    Slieve

    Last modified: 23 May 2020 00:02 | Anonymous member
  • 22 May 2020 19:33
    Reply # 8987117 on 8975930

    Thanks Arne, I hear you. Thanks for being patient with my ignorance. I’m sold on your high AR plan, that you have generously shared here, as the way to go.

  • 22 May 2020 17:05
    Reply # 8986844 on 8975930
    Anonymous member (Administrator)

    Ryan,
    frankly, I think there is too much talking about sail area and too little about vertical height of the sail. Take a look at the diagram with the two sails, below. I would think that the ‘smallest’ sail would be just as fast to windward, as the big one, since they have the same height. Downwind, on the other hand, the big sail would win easily. Ingeborg’s sail is not so tall, in fact, it is lower from tack to peak than the Bermuda rig, so she had no advantage here. In addition, during that little test race, we had no real downwind leg, except for a few boatlengths around B and B’, where Ingeborg quickly walked away from La Barca.
    The hi-AR rig I have drawn for your Alberg 30, is much taller than the Bermuda rig. The vertical height of that sail is 11.02m while the same on the Bermuda rig is only 9.8m. It would not surprise me if the junk-rigged boat would be the faster one in a contest.
    I suggest you wait with the ghoster. You may well find that the JR alone is enough.

    Anyway, good luck  -  you must be pretty sore-eyed after all the advices...

    Arne



    Last modified: 07 Apr 2022 00:21 | Anonymous member (Administrator)
  • 22 May 2020 15:12
    Reply # 8986538 on 8975930

    Arne: looking at your race report I notice you were carrying 45% more sail area than the other boat which you narrowly beat. I’m wondering if expecting on par or better performance from my ideal Bermuda setup (135% Genoa with Code Zero for light air) is overly optimistic? 

    I can’t help but think that the cost of the convenience of the JR will be paid for dearly in performance. 

    I suspect the main issue with the stock rig is its light air performance and I don’t want to make it worse.

  • 22 May 2020 14:51
    Reply # 8986517 on 8975930
    Anonymous member (Administrator)

    Flapping, fluttering, fanning up and wotnot. (Part 2)

    The other main contender to be fitted to that Alberg 30, is the Split Junk Rig, SJR.
    It has been hinted that it may be unsafe for offshore work, partly because it may refuse to feather properly, or it may not last very long because of jiblet fluttering.

    I don’t buy any of these arguments.

    Lack of feathering. Most of those who have the SJR have had no problems with it. Only if you push the balance limit AND cut the jiblet so that they keep on pulling after the mainlets have luffed, will this occur. Anyone can screw up on this, initially, but when it has been put right, then the problem will not suddenly pop up again. Being conservative by nature, I guess I would stop at 33% balance to hedge my bets against bad workmanship (i.e. making jiblets with too narrow sheeting..). The big advantage with the 33% balance versus Ingeborg’s 16%, is both that the sheet forces go radically down, and the yaw moment is greatly reduced on the downwind leg.
    Yesterday afternoon I had a spin in my Ingeborg. On the homeward, downwind leg, the wind suddenly increased until I wondered if I should drop a panel or two. Being only half a mile from harbour, I decided to carry on 7-up. Still, while struggling with keeping a half-straight course, I though to myself;  “Hm, what I could use now, is a squaresail!”. A SJR would be a very good alternative, right then.
    During normal cruising, my rule of thumb is not to carry more sail downwind than I can carry when close-hauled. That ensures easy steering downwind.

    (.. then, in case a sou’wester is blown overboard, I am ready to turn back and pick it up. Nice to know  -  one day the sou’wester may be attached to a fellow...)

    Mast placement. Sometimes the interior of the boat will favour an aft-set mast. Then a La Chica sail (18-22% balance) or the SJR will be the answer. Other times it is the other way around.

    Fluttering jibs. I think this problem has been blown up out of proportions. The SJR jiblets don’t rub on anything, and their chord is so short that the fluttering will be moderate compared to on a real staysail or genoa. Most of these rub on the mast each time one tacks, and the jib on my Johanna even had to rub around a babystay. These sails still last for a good while. Finally, even if those jibs should be blown to shreds in the middle of the Atlantic Ocean, the rest of the sail will bring the boat home just the same, only at a bit slower speed.
    Sooo, don’t make a big problem out of a tiny one.

    My only reason for not trying the SJR, is that I am too lazy, and also content, generally with Ingeborg the way she is.

    Arne


    Last modified: 31 Jan 2021 10:54 | Anonymous member (Administrator)
  • 22 May 2020 13:47
    Reply # 8986401 on 8975930
    Anonymous member (Administrator)

    Flapping, fluttering, fanning up and wotnot. (Part 1)

    During the discussion of which JR suits the Alberg 30 best, it appears that the main contenders are the SJR and the Johanna-style rig (The Johanna rig and the La Chica rig are actually in the same family).
    First a few words in defence of my baby, the Johanna-style rig.
    Apart from all the former jabbering and praising of the rig, the matter of fanning up has been brought up.  Yes, a Hasler-McLeod sail can fan up in a long gybe when deeply reefed, unless one has prevented it from happening: A few years ago, Bob Groves lost his Easy Go, much as a result of the calamities after a fan-up in an offshore gale. After that I have made use of a fan-up preventer (FUP) on my boats. Strictly speaking, for my inshore work, I don’t really need it. Even with two reefs in Ingeborg’s sail, the yard is too long to fan across the topping lifts. I need to take three reefs or more before the yard can pass under it, but that would not be much fun, for sure. Inshore, I can easily get around it in two ways. I can sheet in the relatively small sail and make the gybe short, or I can tack her around  - on Ingeborg there is no such thing as a missed tack. Offshore, tacking around may not be so safe, so a FUP is nice to have.

    So how can I know that it works?
    My FUP system both relies on the FUP line, but I have also beefed up the boom and moved the tackline (TL) aft until it combines to act as a kicking strap (with a stout rubber-snubber on it). I can easily test the function of the FUP: On a calm day, I hoist three or four panels. If I haul in too much on the yard-hauling parrel, YHP, the peak of the yard can easily jump forward of the topping lift. That means trouble, even in the berth. However, if I do things right and then set up the FUP, there is no way the yard can be fanned up, no matter how much I haul on the YHP. The FUP line goes down to the boom, and the boom is held down by the kicker. I like that, and can live with the little extra hassle with using the FUP.

    This suddenly became long-winded, so the flapping, fluttering and SJR will have to wait until the next posting...

    Arne


    Last modified: 31 Jan 2021 10:50 | Anonymous member (Administrator)
  • 22 May 2020 12:10
    Reply # 8986250 on 8975930

    Edward,

    Your comments illustrate very well why the SJR has earned its place in the scheme of things, as I said earlier that it had. It works, there's no doubt about it. It's a good inshore rig. Its 'stresslessness' makes it easy to live with. The battens had been added to the jiblets by the time that video was taken, and though some gentle flapping is evident, it's not very likely that they'll flog themselves to bits in strong winds as a headsail will {I do think it's important to make a distinction between fluttering (due to bad sailmaking), flapping (any cambered sail will do that, battens or no) and flogging (as in a leech unconstrained by battens, or a clew)}

    But I have to ask everyone again the question that I posed earlier, but didn't see any answers: Ryan asked for recommendations for a rig for his intended ocean sailing - who has taken the SJR ocean sailing? Is the SJR a proven offshore rig? Someone has to be first, someone has to be second, but until the pioneering has been done and there is some breadth and depth of experience, I for one cannot do other than advocate conservative design and robust construction. Better to have some headroom when things go pear-shaped in the middle of the ocean, not to have gone for the max (if that's not too many cliches in one sentence). With JR types other than SJR, too, I have a record of advocating a conservative approach - not too big, not too deeply cambered, and so on. Why? Because I've found out from personal experience that moderation in all things makes for a happier ocean sailor.

    Last modified: 22 May 2020 14:03 | Anonymous member
  • 22 May 2020 10:43
    Reply # 8986112 on 8985254
    Deleted user
    Anonymous wrote:

    "Secondly, another valid concern was raised regarding flapping jiblets. I have personally never seen an as lively flapping JR sail as on the SJR. Example in this video. This wear issue concerns both cambered as well as SJR sails, while it ignores flat (hinged/non-hinged) and wingsails. It's simply another thing that should be considered. David in this thread suggests adding battens, while Arne suggests tabling should be sufficient. I don't see how this is poisonous downplaying of the rig, while discussing offshore use - merely reasonable suggestions. I haven't seen Kurt Jon Ulmer on these forums lately but if he was asked about this topic I'm sure he would say that he'd happily live without these issues of all other rigs altogether and sail happily along with his non-flapping flat sail, which he used to point out in a lot of threads in the past. Someone new to JR would definitely get something to ponder out of that, instead of Kurt being downplayed as a hater."

    Hi there,

    'ouf!'  Above shows the danger of quoting 'out of context', (or partisan editing).  Believe or not, I have not seen this  fascinating video until today.  So when i looked at what was shown, I too saw 'flapping jibs' and thought, I don't remember this.

    So I went to Utube and watched the whole excellent video.  In it you see Amiina approaching Tammy, and then 'feathering' the sail to slow down so I could talk to Richard.

    Now you can also see that the wind is very light.  Amiina deliberately has a thicker main sheet than necessary, because of my 'arthritic' hands.  Yet the sail 'feathers' beautifully.  Without any problem at all.

    Personally I have never seen a 'feathered' sail that does not FLAP, be it 'pointy', flat, cambered, or wing.

    The beauty of the SJR is its utter simplicity, & most importantly its 'stresslessness', in use.  There is far less actual stress in the rig itself, and in all the running rigging, than any other boat i have sailed.  It never misses a Beat.  It gybes 'like a butterfly', without any possibility of a 'fans up'.  It de-powers instantly, the moment you release the sheet.  As one reefs, the sail holds its shape and tension perfectly with the 'brilliant' downhauls.

    'ouf!'  I love my sail.  It is the nearest I have come to sailing in harmony with nature, and at peace with myself.  What more can one ask?  

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