New sail for Siskin

<< First  < Prev   1   2   Next >  Last >> 
  • 14 Jul 2021 22:54
    Reply # 10751859 on 10509351
    Anonymous member (Administrator)

    Tuning a SJR

    Antione, The luffs do not have to be taut – just reasonably straight., and the main luff nipped up nicely to the mast.

    If you are attempting to get the luffs straight by strong downward forces – and having to use Hong Kong parrels – then something is wrong. Or, maybe your sail is a very different shape from mine.

    It is not easy to guess – maybe you should post a drawing of your sail plan.

    Without a proper drawing or photograph I can only tell you that on my little boat it took a little while to get everything right – and yes, a little more use of the spanned parrel downhaul pairs is needed when reefed. But not too much, or you will start bending battens. You certainly don’t want the luffs taut like the luff of a Bermudan sail.

    On my little sail, I found it necessary to repeatedly adjust the position of the sling point on the yard – even a few cm made a difference. At the same time, I looked at which battens seemed to be causing a problem and made small adjustments to the points where the parrel downhauls acted on the battens. Some of my battens do need pulling forward a little, which they probably should not need, but reasonable force on the spanned parrel downhaul pairs – correctly placed – is now enough to do it. One good “tweak” on each downhaul pair, after reefing, should be enough. But the main factor in my case was the position of the yard sling point.

    It took a little while to get everything harmonised. You seem to be making progress, so stay patient.

    You will like the sail catcher, I think.

    Maybe, in the end, your sail is a little different from mine, and you just need to find your own way of setting it. How about posting a drawing of your sail?

    Edit: I just looked again at your photo in a previous post. The sail looks good to me, except for that prominent crease in the bottom panel. It reminds me a  bit of a crease I had in one of my jibs, which would not go away whatever I did. I put up with it for a few months, then had a sudden thought - I realised the panel had been sewn on upside down. Might sound stupid, but with that very low angle of rise, the panels look almost the same upside down as right way up. Its important to mark them when making each individual panel. Are you sure you haven't got a panel or two upside down?

    Last modified: 15 Jul 2021 07:42 | Anonymous member (Administrator)
  • 14 Jul 2021 21:07
    Reply # 10751625 on 10509351

    Status update july 14th, writing form Enhuizen harbour riding out N5-6

    Sail works a charm when unreefed and fully hoisted.

    Sail does not work a charm at all when reefed.

    Will change prescribed downhauls to one downhaul per batten to keep luff of the panels stretched / tight and to keep the battens close to the mast. By combining two battens in one downhaul line, I am unable to put enough tension on the luff of the individual panel and therefore cannot go upwind properly.

    Still need a hongkong parel to remove crease from the mainsail parts of the sail.

    I need to get used to the flapping of the sails - I totally forgot how stressing this is!

    Need to add sailcatcher to store reefed parts of the sail.

    Still work in progress.

    To be continued!

  • 30 May 2021 22:19
    Reply # 10575211 on 10509351
    Anonymous member (Administrator)

    Replying to your post 23rd May: On my boat the topping lift is not right at the end of the boom. I made it as far back as possible but still not too far back so the yard escapes when raising the sail – so just one pair of topping lifts is enough to “tame the yard”.

    I have no problem with friction of the batten parrels, or the weight of the sail when hoisting. How much purchase does your halyard have?   However, I did have some problems initially because (1) the mast was not quite high enough – the hoisting point needed to be a little higher, and (2) I needed to have a better way of attaching the halyard blocks to the mast head. There was a lot of friction up there. Lifting the mast a little, and making proper cranes to attach the halyard blocks so they hang vertical, overcame the problem for me. So I suggest check both of those things before just adding more purchase or a winch. I can’t say for other rigs, but on a SJR the mast needs to be a little higher than you might at first think. My “rule of thumb” for the Amiina-type of SJR is: the mast head should be at least as high as the peak of the yard”. Otherwise, the last few cm of sail get very hard to raise.

    Mast crossing the lifts – me too, I did not bother with this as I found it made not much difference.

    • Added batten parrels(?) on the battens 1 & 2, 3 & 4 counting from the top;
    • Did not add downhauls so far

    This I do not understand. The paired-spanned-parrel/downhauls, as designed by Slieve, are a unit. I don’t know how you can have paired batten parrels and not include the downhaul (which is not just a downhaul but also controls the tightness of the parrels). Without a diagram I can not visualise what you have done, but I will just comment that to get the SJR to set nicely the luffs should be straight – and the main luff should be held firmly and neatly to the mast. If you have parrels arranged in some way that you can’t adjust them with downhauls, then maybe they are short parrels and too tight to allow the sail to move easily up and down your mast. I can only guess, but I am guessing this might be the cause of all your problems, including difficult to hoist.

     I suggest you get rid of whatever you have done regarding parrels and use the system which Slieve designed, in which the parrels are very loose, but when the downhaul is tugged it not only hauls down a little on the pair of battens, it also tightens the parrels and nips the luff tight to the mast. As soon as you release the halyard, this takes tension off the parrel downhauls and the parrels are then immediately loose again and the sail can drop easily down the mast. My suggestion is: either use the system as Slieve designed it – or don’t use it at all and instead just use fairly tight individual batten parrels, maybe with beads or something I don’t know.

    All I know is that the system Slieve designed works, but without downhauls being an integrated part of it, I expect it will not work properly.

    Replying to your post 30 May:Actually, your sail looks not too bad in the photo although I can see a rather bad crease in the lowest main panel. You should be able to improve that.

    If you can attach a photo (which you have done) then I suggest making some sketches to explain what you mean, photograph them and add with your post.

    I should add - I do not have wide knowledge on this subject, only what I have learned on my own boat, and maybe you will need to find your own way of doing things. Also maybe some other people, with more knowledge than me, can add some fresh advice.

    It looks to me that you are nearly there – I am sure you will get it right in the end.


    Last modified: 30 May 2021 22:33 | Anonymous member (Administrator)
  • 30 May 2021 20:34
    Reply # 10574987 on 10509351

    This is where we now stand. 

    Still quite some improvements to make.

    Settings are fairly luff-biting - difficult to get the sheet to tiller selfsteering going.

    Siskin seems a bit faster, a bit better on the wind.

    Reefing works well. 0

    Still fiddling with correct settings of the lines on her.

    1 file
  • 23 May 2021 18:43
    Reply # 10540191 on 10509351

    Small status update from setting up Siskin's SJR sail:

    Followed all suggestions and made some other modifications;

    • Moved topping lifts to the aft end of the boom
    • Did away with front of mast crossing of the topping lifts as suggested in PJR & original Coromandel instructions;
    • Maybe have to add one set of lazyjacks to tame the yard - but will try to avoid this;
    • Removed YHP;
    • Added batten parrels(?) on the battens 1 & 2, 3 & 4 counting from the top;
    • Did not add downhauls so far;
    • No downhaul on the boom so far.
    • Very high friction on the halyard at the moment - I think there is too much tension on the lines around the mast (batten parrels??) 

    I think I need to add either a winch or a additional purchase ( is this Englsh???) to the halyard OR lengthen the battenparrels OR add beats to the battenparrels to make them travel up the mast easier OR a combination of all of the above.

    Quite a learning curve this!




  • 16 May 2021 23:18
    Reply # 10514193 on 10509351
    Anonymous member (Administrator)

    I think lazyjacks can be redundant when used with a sail catcher, and interfere slightly with the sail. Apart from that, they are harmless enough, you might as well use what you already have.

    My sheeting system was a first attempt which worked OK so I have not tried to improve it. There may be better ways. It is a two-part system. One sheet controls the top two battens, and the other controls the bottom two and the boom, using the usual sheet spans. (I could not visualise how to make a single sheet). I find the two-sheet system works just fine, mostly they are simply adjusted together. Occasionally one can be adjusted independent of the other, which allows fine tuning of the twist (or I should say, eliminating twist). It works fine but I don’t have a photograph. There are many ways, and there are people much better qualified than me to advise you on sheeting systems.

    You’ll get there Antoine. I messed about every day for a week before getting (most of) the wrinkles out (most of the time). Small adjustments seemed to make quite a difference. Good luck with it – as Paul says, you will be very pleased.


    Edit. Terminology. Some of the junk rig terminology annoys me because it has evolved as a result of careless analogy with Western rigs, the worst example being the term "battens" when referring to those horizontal spars which characterise a junk sail. Never mind - its all history now, and won't change.

    Just to clarify: By "lifts" I mean a pair of lines from the masthead down to the sail catcher, at the mast. This does the job of what PJR refers to as the "mast lift". The other pair of lifts, which go down to the sail-catcher as far aft as practicable, are often referred to (not quite, but approximately correctly) as "topping lifts", and sometimes, quite incorrectly, as "lazyjacks".

    These two lift pairs carry the weight of the bundle: partially, when the sail is reefed, and fully when the sail is fully lowered. Mine are standing lifts, but there are good useful reasons for making them "running", if you can accept the extra running lines, and I will do this next time.

    Lazyjacks are the light lines which form a secondary network from these lifts, to the boom, whose purpose is to muzzle the lowered sail. In the case of SJR with a sail-catcher, they are redundant, unless the lifts are attached directly to the two sail-catcher "stiffener battens "(which is not the best way, and which, in that case, I suppose they help the sail-catcher stiffeners to carry the weight of the bundle).

    Some people also incorrectly refer to the entire assembly of lifts and lazyjacks as "the lazyjacks". 


    Last modified: 16 May 2021 23:51 | Anonymous member (Administrator)
  • 16 May 2021 19:21
    Reply # 10513492 on 10511733
    Anonymous wrote:

    Antoine I don’t fully understand what you have written, without photograph or diagram I find it hard to visualise.

    I can’t visualise the “one running line from the upper batten to the lower batten”. It sounds as though you have just a single line managing all four battens – I can’t see how that works

    >>> That because it does not work. I changed it this afternoon.

    I can comment though, that the parrel-downhauls do work well. One for each batten would be nice, but that’s too many hauling lines – spanning them in pairs, as Slieve has described, makes more sense, managing two battens at a time. So, for your four battens, you need two of these running lines. Apart from your halyard and mainsheet, that’s all the running gear you should need with that rig, if it has the same proportions and geometry as the Amiina sail.

    >>> Created the upper one this afternoon. The lower one has yet to be created.

    In addition to adjusting the sling point of the yard, you might need to experiment a little before finalising exactly where these "parrels" attach to each batten, to get the sail setting perfectly.

    (My boom is pretty light and perhaps because of the sheet span arrangement it floats up a bit, so I have added a standing downhaul on the boom too – which is just a bit of string tied on – that doesn’t normally need any attention, and you may not need it).

    >>> Sounds like a good plan. Would be interested in the sheet arrangement.

    The fixed attachments of halyard & boom to mast I find very appealing. My mast consists of two widths/dimensions as I have a sleeve (yes another one....) around the mast to enable lowering the thing.  Sorry, I don't understand any of that. Can you add some diagrams?

    Coromandels have a mast that can split somewhere below the middle. Richard has a picture of it on his site here:

    https://tammynorie.wordpress.com/2014/06/21/mast-raising-demonstration/

    I can agree with you that the split junk rig is untidy when reefed – the jibs won’t stay in conventional lazyjacks, as you have found. For a boat this size with SJR I cannot recommend more strongly the sail catcher as devised by Slieve. But it can be simplified. You don’t need a wishbone at each end – just the two stiffener “battens” each side.


    Diagram shows the wishbone on Amiina (upper photo). Mine broke and I found it was not necessary (lower photo)

    >>> I followed your example - I proceed without the wishbone ends.

    For a sail this size you don’t need (and in my opinion don’t want) lazyjacks. Just two lift pairs – one at the mast where it will not interfere at all with the SJR sail – and the other (sometimes referred to as a "topping lift" as far aft on the boom as you can go provided it still captures the yard when you lower the sail. 

    The photo shows one side of the two lift pairs, in white. (The parrel downhauls are not visible here).

    >>> I will need to simplify my lazyjack arrangement a bit then. I still use the set up as proposed for the original Coromandel rig.

    I suggest you do not attach the lifts to the boom – and also do not attach the lifts directly to the two “batten” stiffeners on the sail catcher. Instead, attach the lifts to the sail catcher itself. That way the stiffeners merely stiffen the top of the sail catcher but do not carry a lot of weight – they can then be quite light. The weight of the bundle is carried by the sail catcher itself, via the lifts. This arrangement works well, not only muzzles the sail, but also can act as a sail cover – and a handy repository for your boat hook.

    >>> Yes my prototype works the way you describe it here. I red your earlier contributions.

    Spanned parrel downhauls, and sail catcher. I bless Slieve every time I raise my SJR sail!

    >>> Same here but I have some way to go to get the whole thing going. Today the sail was a bag of wringles so I still have a ways to go.

    Thanks for all input!!!



  • 16 May 2021 12:26
    Reply # 10511733 on 10509351
    Anonymous member (Administrator)

    Antoine I don’t fully understand what you have written, without photograph or diagram I find it hard to visualise.

    I can’t visualise the “one running line from the upper batten to the lower batten”. It sounds as though you have just a single line managing all four battens – I can’t see how that works

    I can comment though, that the parrel-downhauls do work well. One for each batten would be nice, but that’s too many hauling lines – spanning them in pairs, as Slieve has described, makes more sense, managing two battens at a time. So, for your four battens, you need two of these running lines. Apart from your halyard and mainsheet, that’s all the running gear you should need with that rig, if it has the same proportions and geometry as the Amiina sail.

    In addition to adjusting the sling point of the yard, you might need to experiment a little before finalising exactly where these "parrels" attach to each batten, to get the sail setting perfectly.

    (My boom is pretty light and perhaps because of the sheet span arrangement it floats up a bit, so I have added a standing downhaul on the boom too – which is just a bit of string tied on – that doesn’t normally need any attention, and you may not need it).

    The fixed attachments of halyard & boom to mast I find very appealing. My mast consists of two widths/dimensions as I have a sleeve (yes another one....) around the mast to enable lowering the thing.  Sorry, I don't understand any of that. Can you add some diagrams?

    I can agree with you that the split junk rig is untidy when reefed – the jibs won’t stay in conventional lazyjacks, as you have found. For a boat this size with SJR I cannot recommend more strongly the sail catcher as devised by Slieve. But it can be simplified. You don’t need a wishbone at each end – just the two stiffener “battens” each side.


    Diagram shows the wishbone on Amiina (upper photo). Mine broke and I found it was not necessary (lower photo)

    For a sail this size you don’t need (and in my opinion don’t want) lazyjacks. Just two lift pairs – one at the mast where it will not interfere at all with the SJR sail – and the other (sometimes referred to as a "topping lift" as far aft on the boom as you can go provided it still captures the yard when you lower the sail. 

    The photo shows one side of the two lift pairs, in white. (The parrel downhauls are not visible here).

    I suggest you do not attach the lifts to the boom – and also do not attach the lifts directly to the two “batten” stiffeners on the sail catcher. Instead, attach the lifts to the sail catcher itself. That way the stiffeners merely stiffen the top of the sail catcher but do not carry a lot of weight – they can then be quite light. The weight of the bundle is carried by the sail catcher itself, via the lifts. This arrangement works well, not only muzzles the sail, but also can act as a sail cover – and a handy repository for your boat hook.

    Spanned parrel downhauls, and sail catcher. I bless Slieve every time I raise my SJR sail!


    Last modified: 16 May 2021 15:13 | Anonymous member (Administrator)
  • 16 May 2021 11:40
    Reply # 10511547 on 10509562
    Anonymous wrote:

    Hi Antoine,

    I see from your profile that your previous sail was flat panels.

    If you haven’t already tried the new sail you’re in for a surprise heehee..

    It looks to me that you may have the sling point on the yard a little too far aft - this would account both for the luff of your top main panel being forward of the mast, and for the diagonal crease in the top main.

    When I was setting mine up the Wizard  suggested trying moving the sling point until only a light pull on the combined batten parrel/downhauls brought the luff of the mains happily at a vertical line ideally at the forward edge of the mast (mine are a little aft of that).

    When you find the right spot you shouldn’t need the throat hauling parrel (the downhaul of which I see is interfering with the inflation of your top jiblet). I don’t need one, I just have paired combined parrel/down hauls on battens (numbered bottom up) 1&2, 3&4, and a single parrel/downhaul on batten 5, and a yard hauling parrel from the sling point.

    It looks great, you’re going to have a lot of fun.

    Thank you for all the kind words!

    I take this to mean that I have to move the contact point between halyard and yard forward on the yard - as in: towards the direction of the bow.

    This is indeed in the stars. We build the sail with a Laser-like sleeve around the yard. This will have to wait a bit till I have an inventory of all corrections needed to turn my father's gift (which this sail is!) into My Father's Gift.

    I will then ask Frank van Zoest to implement all improvements in one go. Another point of attention is the sailcatcher / lazy jack arrangement. I am now experimenting with a prototype and reading up on the issue. Please keep on sending these corrections, remarks, suggestions for improvement etc.

    The fixed attachments of halyard & boom to mast I find very appealing. My mast consists of two widths/dimensions as I have a sleeve (yes another one....) around the mast to enable lowering the thing. Implementing this suggestion might take some pondering.

    What I can implement myself are he downhauls. I now have one running line from the upper batten to the lower batten. Not a good idea? A long line indeed but long tailed lines have never bothered me much.

    My list for this project now consists of:

    • Moving halyard on yard i.e.: add opening in yard sleeve;
    • Adding "contact points" on boom to enable contact between rig & sailcatcher;
    • Sailcatcher: convert plastic prototype to reliable working device;
    • Improve lazy jacks setup so jiblets can be tamed while sailing reefed;
    • Test various downhaul arrangements;
    • Design fixed connections between halyard & boom and mast.


  • 16 May 2021 10:55
    Reply # 10511396 on 10509705
    Anonymous wrote:

    I concur with Paul, if you get the sling point right and with a little bit of "fiddling" you won't need a throat-hauling parrel - in fact I would go further.

    On Serendipity I have recently added a fixed parrel for the yard and another for the boom, but the only running gear needed is just the halyard and the two paired spanned parrel-downhauls as used by Slieve.

    It seemed a mess at first, but with a little tuning the sail now sets well with just the above running gear. For some reason, mine seems to set happily with the main luffs in line with the aft edge of the mast.

    However, Its all very much related to the geometric profile of the sail itself - I copied Amiina's exactly, and it looks as though Paul has too. Yours looks similar, but I can't see if it is an exact geometric copy or not.

    Your sail looks to have fairly small amount of camber. I am interested to know: what is the calculated amount of camber you have built into the jibs and main panels, and what is the sheeting angle of the jibs? Thanks.


    Camber drawn 10%. Will have to measure how much it actually is while underway. "Stay tuned" as they say these days.

    Added quite a bit of sailarea (2 m2 as in an addition of 10% compared to the original 18m2).

<< First  < Prev   1   2   Next >  Last >> 
       " ...there is nothing - absolutely nothing - half so much worth doing as simply messing about in junk-rigged boats" 
                                                               - the Chinese Water Rat

                                                              Site contents © the Junk Rig Association and/or individual authors

Powered by Wild Apricot Membership Software